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Home | Alpha Telephone | Domain Names | Web Hosting | Get Traffic | xrEvidence | xrSoccer United States Patent
Cephalosporin antibiotics Process and intermediate products useful in the preparation of cephalosporin compounds having a substituent at the 7-position in place of hydrogen are provided. The new cephalosporin compounds are active against various gram-negative and gram-positive organisms.
Attorney, Agent or Firm: This is a division of application Ser. No. 149,364, filed June 2, 1971, U.S. Pat. No. 4,297,488. What is claimed is: 1. The compound of 3-A-7-X'-7-acylamido-3-cephem-4-carboxylic acid wherein X' is chloro, bromo or iodo; A is methyl, hydroxymethyl, chloromethyl, bromomethyl, or fluoromethyl, mercaptomethyl, methoxymethyl, n-propoxymethyl, methylthiomethyl, acetoxymethyl, propionyloxymethyl, benzoyloxymethyl, (p-chlorobenzoyl)oxymethyl, (p-methylbenzoyl)oxymethyl, pivaloyloxymethyl, (1-adamantyl)carboxymethyl, butanoyloxymethyl, carbamoyloxymethyl, (N-methylcarbamoyl)oxymethyl, (N-ethylcarbamoyl)oxymethyl, [N-(2-chloroethyl)carbamoyl]oxymethyl, (N-phenylcarbamoyl)oxymethyl, (N-p-sulfophenylcarbamoyl)oxymethyl, p-carboxymethylphenylcarbamoyloxymethyl, methoxycarbonyloxymethyl, isobutanoyloxymethyl, cyclobutylcarbonyloxymethyl, carbamoylthiomethyl, (ethoxythiocarbonyl)thiomethyl, (n-propoxythiocarbonyl)thiomethyl, (cyclopentanoxythiocarbonyl)thiomethyl, N,N-diethylthiocarbamoylthiomethyl, N-methylpiperazinium-1-thiocarbonylthi omethyl, N,N-dimethylpiperazinium-1-thiocarbonylthiomethyl, 2-furoylthiomethyl, isothiouroniummethyl, (5-methyl-1,3,4-thiadiazol-2-yl)-thiomethyl, p-tolylsulfonylthiomethyl, mesyloxymethyl, 1-methyl-1,2,3,4-tetrazolyl-5-thiomethyl, tosyloxymethyl, sulfamoyloxymethyl, 1-naphthoyloxymethyl, 2-furylacetoxymethyl, cinnamoyloxymethyl, p-hydroxycinnamoyloxymethyl, p-sulfocinnamoyloxymethyl and 1R:2S-epoxypropylphosphonyloxymethyl, or pyridinium methyl; and acylamido is ##STR130## wherein n is 1-4, Z is oxygen or sulfur, and R" is benzyl, p-hydroxybenzyl, 4-amino-4-carboxybutyl, methyl, cyanomethyl, 2-pentenyl, n-amyl, n-heptyl, ethyl, 3- or 4-nitrobenzyl, phenethyl, .beta.,.beta.-diphenylethyl, methyldiphenylmethyl, triphenylmethyl, 2-methoxyphenyl, 2,6-dimethoxyphenyl, 2,4,6-trimethoxyphenyl, 3,5-dimethyl-4-isoxazolyl, 3-butyl-5-methyl-4-isoxazolyl, 5-methyl-3-phenyl-4-isoxazolyl, 3-(2-chlorophenyl)-5-methyl-4-isoxazolyl, 3-(2,6-dichlorophenyl)-5-methyl-4-isoxazolyl, D-4-amino-4-carboxybutyl, D-4-N-benzoylamino-4-carboxy-n-butyl, p-aminobenzyl, o-aminobenzyl, m-aminobenzyl, (3-pyridyl)-methyl, 2-ethoxy-1-naphthyl, 3-carboxy-2-quinoxalinyl, 3-(2,6-dichlorophenyl)-5-(2-furyl)-4-isoxazolyl, 3-phenyl-4-isoxazolyl, 5-methyl-3-(4-guanidinophenyl)-4-isoxazolyl, 4-guanidinomethylphenyl, 4-guanidinomethylbenzyl, 4-guanidinobenzyl, 4-guanidinophenyl, 2,6-dimethoxy-4-guanidinophenyl, o-sulfobenzyl, p-carboxymethylbenzyl, p-carbamoylmethylbenzyl, m-fluorobenzyl, m-bromobenzyl, p-chlorobenzyl, p-methoxybenzyl, 1-naphthylmethyl, 3-isothiazolylmethyl, 4-isothiazolylmethyl, 5-isothiazolylmethyl, 4-pyridylmethyl, 5-isoxazolylmethyl, 4-methoxy-5-isoxazolylmethyl, 4-methyl-5-isoxazolylmethyl, 1-imidazolylmethyl, 2-benzofuranylmethyl, 2-indolylmethyl, 2-phenylvinyl, 2-phenylethynyl, 2-(5-nitrofuranyl)vinyl, phenyl, o-methoxyphenyl, o-chlorophenyl, o-phenylphenyl, p-aminomethylbenzyl, 1-(5-cyanotriazolyl)methyl), difluoromethyl, dichloromethyl, dibromomethyl, 1-(3-methylimidazolyl)methyl, 2- or 3-(5-carboxymethylthienyl)methyl, 2- or 3-(4-carbamoylthienyl)methyl, 2- or 3-(5-methylthienyl)methyl, 2- or 3-(5-methoxythienyl)methyl, 2- or 3-(4-chlorothienyl)methyl, 2- or 3-(sulfothienyl)methyl, 2- or 3-(5-carboxythienyl)methyl, 3-(1,2,5-thiadiazolyl)methyl, 3-(4-methoxy-1,2,5-thiadiazolyl)methyl, 2-furylmethyl, 2-(5-nitrofuryl)methyl, 3-furylmethyl, 2-thienylmethyl, 3-thienylmethyl, and tetrazolylmethyl; and the pharmaceutically acceptable salts thereof, or the carboxylic acid protecting derivatives thereof wherein the derivative group is methyl, t-butyl, trichloroethyl, allyl, propargyl, benzyl, diphenylmethyl, o-nitrobenzyl, 3,5-dinitrobenzyl, p-methoxybenzyl, acetoxymethyl, pivaloyloxymethyl, phenacyl, trichloroethoxy carbonyl, trimethylsilyl or tributyltin. 2. The compound 3-A-7-X'-7-acylamido-3-cephem-4-carboxylic acid wherein X' is chloro, bromo or iodo; A is methyl, hydroxymethyl, chloromethyl, bromomethyl, or fluoromethyl, mercaptomethyl, methoxymethyl, n-propoxymethyl, methylthiomethyl, acetoxymethyl, propionyloxymethyl, benzoyloxymethyl, (p-chlorobenzoyl)oxymethyl, (p-methylbenzoyl)oxymethyl, pivaloyloxymethyl, (1-adamantyl)carboxymethyl, butanoyloxymethyl, carbamoyloxymethyl, (N-methylcarbamoyl)oxymethyl, (N-ethylcarbamoyl)oxymethyl, [N-(2-chloroethyl)carbamoyl]oxymethyl, (N-phenylcarbamoyl)oxymethyl, (N-p-sulfophenylcarbamoyl)oxymethyl, p-carboxymethylphenylcarbamoyloxymethyl, methoxycarbonyloxymethyl, isobutanoyloxymethyl, cyclobutylcarbonyloxymethyl, carbamoylthiomethyl, (ethoxythiocarbonyl)thiomethyl, (n-propoxythiocarbonyl)thiomethyl, (cyclopentanoxythiocarbonyl)thiomethyl, N,N-diethylthiocarbamoylthiomethyl, N-methylpiperazinium-1-thiocarbonylthi omethyl, N,N-dimethylpiperzinium-1-thiocarbonylthiomethyl, 2-furoylthiomethyl, isothiouroniummethyl, (5-methyl-1,3,4-thiadiazol-2-yl)-thiomethyl, p-tolylsulfonylthiomethyl, mesyloxymethyl, 1-methyl-1,2,3,4-tetrazolyl-5-thiomethyl, tosyloxymethyl, sulfamoyloxymethyl, 1-naphthoyloxymethyl, 2-furylacetoxymethyl, cinnamoyloxymethyl, p-hydroxycinnamoyloxymethyl, p-sulfocinnamoyloxymethyl and 1R:2S-epoxypropylphosphonyloxymethyl, or pyridinium methyl; and acylamido is ##STR131## wherein R" is benzyl, p-hydroxybenzyl, 4-amino-4-carboxybutyl, methyl, cyanomethyl, 2-pentenyl, n-amyl, n-heptyl, ethyl, 3- or 4-nitrobenzyl, phenethyl, .beta.,.beta.-diphenylethyl, methyldiphenylmethyl, triphenylmethyl, 2-methoxyphenyl, 2,6-dimethoxyphenyl, 2,4,6-trimethoxyphenyl, 3,5-dimethyl-4-isoxazolyl, 3-butyl-5-methyl-4-isoxazolyl, 5-methyl-3-phenyl-4-isoxazolyl, 3-(2-chlorophenyl)-5-methyl-4-isoxazolyl, 3-(2,6-dichlorophenyl)-5-methyl-4-isoxazolyl-D-4-amino 4-carboxybutyl, D-4-N-benzoylamino-4-carboxy-n-butyl, p-aminobenzyl, o-aminobenzyl, m-aminobenzyl, (3-pyridyl)-methyl, 2-ethoxy-1-naphthyl, 3-carboxy-2-quinoxalinyl, 3-(2,6-dichlorophenyl)-5-(2-furyl)-4-isoxazolyl, 3-phenyl-4-isoxazolyl, 5-methyl-3-(4-guanidinophenyl)-4-isoxazolyl, 4-guanidinomethylphenyl, 4-guanidinomethylbenzyl, 4-guanidinobenzyl, 4-guanidinophenyl, 2,6-dimethoxy-4-guanidinophenyl, o-sulfobenzyl, p-carboxymethylbenzyl, p-carbamoylmethylbenzyl, m-fluorobenzyl, m-bromobenzyl, p-chlorobenzyl, p-methoxybenzyl, 1-naphthylmethyl, 3-isothiazolylmethyl, 4-isothiazolylmethyl, 5-isothiazolylmethyl, 4-pyridylmethyl, 5-isoxazolylmethyl, 4-methoxy-5-isoxazolylmethyl, 4-methyl-5-isoxazolylmethyl, 1-imidazolylmethyl, 2-benzofuranylmethyl, 2-indolylmethyl, 2-phenylvinyl, 2-phenylethynyl, 2-(5-nitrofuranyl)vinyl, phenyl, o-methoxyphenyl, o-chlorophenyl, o-phenylphenyl, p-aninomethylbenzyl, 1-(5-cyanotriazolyl)methyl), difluoromethyl, dichloromethyl, dibromomethyl, 1-(3-methylimidazolyl)methyl, 2- or 3-(5-carboxymethylthienyl)methyl, 2- or 3-(carbamoylthienyl)methyl, 2- or 3-(5-methylthienyl)methyl, 2- or 3-(5-methoxythienyl)methyl, 2- or 3-(4-chlorothienyl)methyl, 2- or 3-(sulfothienyl)methyl, 2- or 3-(5-carboxythienyl)methyl, 3-(1,2,5-thiadiazolyl)methyl, 3-(4-methoxy-1,2,5-thiadiazolyl)methyl, 2-furylmethyl, 2-(5-nitrofuryl)methyl, 3-furylmethyl, 2-thienylmethyl, 3-thienylmethyl, and tetrazolylmethyl; and the pharmaceutically acceptable salts thereof, or the carboxylic acid protecting derivatives thereof wherein the derivative group is methyl, t-butyl, trichloroethyl, allyl, propargyl, benzyl, diphenylmethyl, o-nitrobenzyl, 3,5-dinitrobenzyl, p-methoxybenzyl, acetoxymethyl, pivaloyloxymethyl, phenacyl, trichlorethoxy carbonyl, trimethylsilyl or tributyltin. 3. The compound 3-A-7-X'-7-acylamido-3-cephem-4-carboxylic acid wherein X' is chloro, bromo or iodo; A is methyl, hydroxymethyl, chloromethyl, bromomethyl, or fluoromethyl, mercaptomethyl, methoxymethyl, n-propoxymethyl, methylthiomethyl, acetoxymethyl, propionyloxymethyl, benzoyloxymethyl, (p-chlorobenzoyl)oxymethyl, (p-methylbenzoyl)oxymethyl, pivaloyloxymethyl, (1-adamantyl)carboxymethyl, butanoyloxymethyl, carbamoyloxymethyl, (N-methylcarbamoyl)oxymethyl, (N-ethylcarbamoyl)oxymethyl, [N-(2-chloroethyl)carbamoyl]oxymethyl, (N-phenylcarbamoyl)oxymethyl, (N-p-sulfophenylcarbamoyl)oxymethyl, p-carboxymethylphenylcarbamoyloxymethyl, methoxycarbonyloxymethyl, isobutanoyloxymethyl, cyclobutylcarbonyloxymethyl, carbamoylthiomethyl, (ethoxythiocarbonyl)thiomethyl, (n-propoxythiocarbonyl)thiomethyl, (cyclopentanoxythiocarbonyl)thiomethyl, N,N-diethylthiocarbamoylthiomethyl, N-methylpiperazinium-1-thiocarbonylthi omethyl, N,N-dimethylpiperzinium-1-thiocarbonylthiomethyl, 2-furoylthiomethyl, isothiouroniummethyl, (5-methyl-1,3,4-thiadiazol-2-yl)-thiomethyl, p-tolylsulfonylthiomethyl, mesyloxymethyl, 1-methyl-1,2,3,4-tetrazolyl-5-thiomethyl, tosyloxymethyl, sulfamoyloxymethyl, 1-naphthoyloxymethyl, 2-furylacetoxymethyl, cinnamoyloxymethyl, p-hydroxycinnamoyloxymethyl, p-sulfocinnamoyloxymethyl and 1R:2S-epoxypropylphosphonyloxymethyl, or pyridinium methyl; and acylamido is ##STR132## wherein R"' is .alpha.-aminobenzyl, .alpha.-amino-2-thenyl, .alpha.-methylaminobenzyl, .alpha.-amino-.gamma.-methylmercaptopropyl, .alpha.-amino-3 or 4-chlorobenzyl, .alpha.-amino-3 or 4-hydroxybenzyl, .alpha.-amino-2,4-dichlorobenzyl, .alpha.-amino-3,4-dichlorobenzyl, D(-)-.alpha.-hydroxybenzyl, .alpha.-carboxybenzyl, .alpha.-amino-3-thenyl, .alpha.-amino-2-thenyl, D(-)-.alpha.-3-chloro-4-hydroxybenzyl, D(-)-.alpha.-amino-3-thenyl, 1-aminocyclohexyl, .alpha.-(5-tetrazolyl)benzyl, .alpha.-sulfaminobenzyl, .alpha.-sulfamino-3-thenyl, .alpha.-(N-methylsulfamino)benzyl, D(-)-.alpha.-guanidino-2-thenyl, D(-)-.alpha.-guanidinobenzyl, .alpha.-guanylureidobenzyl, .alpha.-hydroxybenzyl, .alpha.-azidobenzyl, .alpha.-fluorobenzyl, 4-(5-methoxy-2,3-oxadiazole)aminomethyl, 4-(5-methoxy-1,3-oxadiazole)hydroxymethyl, 4-(5-methoxy-1,3-oxadiazole)carboxymethyl, 4-(5-methoxy-1,3-sulfadiazole)aminomethyl, 4-(5-methoxy-1,3-sulfadiazole)hydroxymethyl, 4-(5-methoxy-1,3-sulfadiazole) carboxymethyl, 2-(5-chlorothienyl)-aminomethyl, 2-(5-chlorothienyl)-hydroxymethyl, 2-(5-chlorothienyl)carboxymethyl, 3-(1,2-thiazole)-aminomethyl, 3-(1,2-thiazole)-hydroxymethyl, 3-(1,2-thiazole)carboxymethyl, 2-(1,4-thiazolyl)-aminomethyl, 2-(1,4-thiazolyl)hydroxymethyl, 2-(1,4-thiazolyl)carboxymethyl, 2-benzothienylaminomethyl, 2-benzothienylhydroxymethyl, 2-benzothienylcarboxymethyl, 2-azidooctyl-3-phenyl-3-azidomethyl, .alpha.-sulfobenzyl, and .alpha.-phosphonobenzyl; and the pharmaceutically acceptable salts thereof, or the carboxylic acid protecting derivatives thereof wherein the derivative group is methyl, t-butyl, trichloroethyl, allyl, propargyl, benzyl, diphenylmethyl, o-nitrobenzyl, 3,5-dinitrobenzyl, p-methoxybenzyl, acetoxymethyl, pivaloyloxymethyl, phenacyl, trichloroethoxy carbonyl, trimethylsilyl or tributyltin. 4. The compound having the formula ##STR133## wherein X' is chloro, bromo or iodo; ##STR134## is phenylacetamido, 2-thienylacetamido, 2-furylacetamido, phenylthioacetamido, phenoxyacetamido, 2-amino-2-phenylacetamido or 2-azido-2-phenylacetamido; the pharmaceutically acceptable salts thereof; and the carboxylic acid protecting derivatives thereof wherein the derivative group is methyl, t-butyl, trichloroethyl, allyl, propargyl, benzyl, diphenylmethyl, o-nitrobenzyl, 3,5-dinitrobenzyl, p-methoxybenzyl, acetoxymethyl, pivaloyloxymethyl, phenacyl, trichloroethoxy carbonyl, trimethylsilyl or tributyltin. 5. The compound having the formula ##STR135## wherein X' is chloro, bromo or iodo; ##STR136## is acetamido, phenylacetamido, phenoxyacetamido, (2-thienyl)acetamido, (2-furyl)acetamido, 2-azido-2-phenyl acetamido, 2-amino-2-phenyl acetamido, 2-carboxy-2-phenylacetamido, 2-fluoro-2-phenylacetamido, 2-sulfoamino-2-phenylacetamido, (2-thianaphthene)acetamido, tetrazolylacetamido, or (p-guanidinophenyl)acetamido; the pharmaceutically acceptable salts thereof; and the carboxylic acid protecting derivatives wherein the derivative group is methyl, t-butyl, trichloroethyl, allyl, propargyl, benzyl, diphenylmethyl, o-nitrobenzyl, 3,5-dinitrobenzyl, p-methoxybenzyl, acetoxymethyl, pivaloyloxymethyl, phenacyl, trichloroethoxy carbonyl, trimethylsilyl or tributyltin. 6. The compound of the formula: ##STR137## wherein X' is chloro, bromo, or iodo; and X is hydrogen or a pharmaceutically acceptable salt. 7. The sodium salt of 3-carbamoyloxymethyl-7-chloro-7-(2-thienylacetamido)-3-cephem-4-carboxylic acid. 8. The calcium salt of 3-carbamoyloxymethyl-7-chloro-7-(2-thienylacetamido)-3-cephem-4-carboxylic acid. 9. The compound 3-carbamoyloxymethyl-7-chloro-7-(2-furylacetamido)-3-cephem-4-carboxylic acid and the pharmaceutically acceptable salt thereof. 10. The compound 3-carbamoyloxymethyl-7-chloro-7-tetrazolylacetamido-3-cephem-4-carboxylic acid and the pharmaceutically acceptable salts thereof. 11. The compound 3-acetoxymethyl-7-chloro-7-(2-carboxy-2-phenylacetamido)-3-cephem-4-carbox ylic acid and the pharmaceutically acceptable salts thereof. This invention relates to new antibiotics, new intermediate products useful in the preparation of these antibiotics, and processes for the preparation of these compounds. More particularly, it is concerned with new 7-aminocephalosporanic acid derivatives having a substituent at position 7, and with new intermediates and processes for their production. The discovery of penicillin, which was found to be such an important and effective antibiotic, stimulated great interest in this field. Subsequently, various other antibiotics such as streptomycin, the tetracyclines, novobiocin, and the like were found which greatly increased the doctors' armamentarium for treating infections due to a variety of pathogens. Unfortunately, the use of these antibiotics gave rise to strains of pathogens resistant to these known antibiotics. In addition, the known antibiotics suffer from the disadvantage that they are only effective against certain types of microorganisms and are not effective against a broad range of pathogens. Accordingly, the search for other antibiotics has continued. It is an object of this invention to provide new cephalosporins having antibiotic activity. A further object is to provide processes for the preparation of these new antibiotics. Another object is to provide new intermediates useful in preparing these new cephalosporins. Other objects will be apparent from the detailed description of this invention hereinafter provided. The new cephalosporins of the present invention are compounds wherein the .DELTA..sup.3 -cepham nucleus, namely a dehydrothiazine ring with a fused .beta.-lactam, contains a substituent at the 7 position. Thus, these new cephalosporins which can be represented by the structural formula ##STR1## wherein R' represents an acyl group, A represents an organic radical or group, and R.sub.1 represents a radical or group replacing hydrogen, and the derivatives thereof such as esters, amides and salts are valuable new antibiotic substances. The acyl radical represented by R' can be a substituted or unsubstituted aliphatic, aromatic or heterocyclic, araliphatic or heterocyclylaliphatic carboxylic acid radical or a carbothioic acid radical such as the acyl radicals of the known cephalosporins and penicillins. These acyl radicals can be represented by the general formula ##STR2## where R.sub.2 is a radical of the group defined below, m and n represent 0-4 and R.sub.3 represents R" or ZR", which are defined below. One group of acyl radicals can be represented by the acyl group general formula ##STR3## wherein R" represents a substituted or unsubstituted straight or branched chain alkyl, alkenyl or alkynyl group; aryl, aralkyl; cycloalkyl; or a heteroaryl or heteroaralkyl group. These groups can be unsubstituted or can be substituted by radicals such as alkyl, alkoxy, halo, cyano, carboxy, sulfoamino, carbamoyl, sulfonyl, azido, amino, substituted amino, haloalkyl, carboxyalkyl, carbamoylalkyl, N-substituted carbamoylalkyl, guanidino, N-substituted guanidino, guanidinoalkyl, and the like. Representative examples of such acyl groups that might be mentioned are those wherein R" is benzyl, p-hydroxybenzyl, 4-amino-4-carboxybutyl, methyl, cyanomethyl, 2-pentenyl, n-amyl, n-heptyl, ethyl, 3- or 4-nitrobenzyl, phenethyl, .beta.,.beta.-diphenylethyl, methyldiphenylmethyl, triphenylmethyl, 2-methoxyphenyl, 2,6-dimethoxyphenyl, 2,4,6-trimethoxyphenyl, 3,5-dimethyl-4-isoxazolyl, 3-butyl-5-methyl-4-isoxazolyl, 5-methyl-3-phenyl-4-isoxazolyl, 3-(2-chlorophenyl)-5-methyl-4-isoxazolyl, 3-(2,6-dichlorophenyl)-5-methyl-4-isoxazolyl, D-4-amino-4-carboxybutyl, D-4-N-benzoylamino-4-carboxy-n-butyl, p-aminobenzyl, o-aminobenzyl, m-aminobenzyl, (3-pyridyl)methyl, 2-ethoxy-1-naphthyl, 3-carboxy-2-quinoxalinyl, 3-(2,6-dichlorophenyl)-5-(2-furyl)-4-isoxazolyl, 3-phenyl-4-isoxazolyl, 5-methyl- 3-(4-guanidinophenyl)-4-isoxazolyl, 4-guanidinomethylphenyl, 4-guanidinomethylbenzyl, 4-guanidinobenzyl, 4-guanidinophenyl, 2,6-dimethoxy-4-guanidinophenyl, o-sulfobenzyl, p-carboxymethylbenzyl, p-carbamoylmethylbenzyl, m-fluorobenzyl, m-bromobenzyl, p-chlorobenzyl, p-methoxybenzyl, 1-naphthylmethyl, 3-isothiazolylmethyl, 4-isothiazolylmethyl, 5-isothiazolylmethyl, 4-pyridylmethyl, 5-isoxazolylmethyl, 4-methoxy-5-isoxazolylmethyl, 4-methyl-5-isoxazolylmethyl, 1-imidazolylmethyl, 2-benzofuranylmethyl, 2-indolylmethyl, 2-phenylvinyl, 2-phenylethynyl, 2-(5-nitrofuranyl)vinyl, phenyl, o-methoxyphenyl, o-chlorophenyl, o-phenylphenyl, p-aminomethylbenzyl, 1-(5-cyanotriazolyl)methyl, difluoromethyl, dichloromethyl, dibromomethyl, 1-(3-methylimidazolyl)methyl, 2- or 3-(5-carboxymethylthienyl)methyl, 2- or 3-(4-carbamoylthienyl)methyl, 2- or 3-(5-methylthienyl)methyl, 2- or 3-(5-methoxythienyl)methyl, 2- or 3-(4-chlorothienyl)methyl, 2- or 3-(5-sulfothienyl)methyl, 2- or 3-(5-carboxythienyl)methyl, 3-(1,2,5-thiadiazolyl)methyl, 3-(4-methoxy-1,2,5-thiadiazolyl)methyl, 2-furylmethyl, 2-(5-nitrofuryl)methyl, 3-furylmethyl, 2-thienylmethyl, 3-thienylmethyl, and tetrazolylmethyl. The acyl group can also be a radical of the formula ##STR4## wherein n is 0-4, Z represents oxygen or sulfur, and R" is defined as above. Representative members of the substituent that might be mentioned are allylthiomethyl, phenylthiomethyl, butylmercaptomethyl, .alpha.-chlorocrotylmercaptomethyl, phenoxymethyl, phenoxyethyl, phenoxybutyl, phenoxybenzyl, diphenoxymethyl, dimethylmethoxymethyl, dimethylbutoxymethyl, dimethylphenoxymethyl, 4-guanidinophenoxymethyl, 4-pyridylthiomethyl, p-(carboxymethyl)phenoxymethyl, p-(carboxymethyl)phenylthiomethyl, 2-thiazolylthiomethyl, p-(sulfo)phenoxymethyl, p-(sulfo)phenylthiomethyl, p-(carboxy)phenoxymethyl, p-(carboxy)phenylthiomethyl, p-(carboxymethyl)phenoxymethyl, p-(carboxymethyl)phenylthiomethyl, 2-pyrimidinylthiomethyl, phenethylthiomethyl, 1-(5,6,7,8-tetrahydronaphthyl)oxomethyl, 6,8-bis(methylthio)octanoyl. Alternatively, the acyl group can be a radical of the formula ##STR5## wherein R" is defined as above and R"' is a radical such as amino, hydroxy, azido, carbamoyl, guanidino, acyloxy, halo, sulfamino, tetrazolyl, sulfo, carboxy, carbalkoxy, and the like. Representative members of the substituent ##STR6## that might be mentioned are .alpha.-aminobenzyl, .alpha.-amino-2-thenyl, .alpha.-methylaminobenzyl, .alpha.-amino-.gamma.-methylmercaptopropyl, .alpha.-amino-3 or 4-chlorobenzyl, .alpha.-amino-3 or 4-hydroxybenzyl, .alpha.-amino-2,4-dichlorobenzyl, .alpha.-amino-3,4-dichlorobenzyl, D(-)-.alpha.-hydroxybenzyl, .alpha.-carboxybenzyl, .alpha.-amino-3-thenyl, .alpha.-amino-2-thenyl, D(-)-.alpha.-amino-3-chloro-4-hydroxybenzyl, D(-)-.alpha.-amino-3-thenyl, 1-aminocyclohexyl, .alpha.-(5-tetrazolyl)benzyl, .alpha.-sulfaminobenzyl, .alpha.-sulfamino-3-thenyl, .alpha.-(N-methylsulfamino)benzyl, D(-)-.alpha.-guanidino-2-thenyl, D(-)-.alpha.-guanidinobenzyl, .alpha.-guanylureidobenzyl, .alpha.-hydroxybenzyl, .alpha.-azidobenzyl, .alpha.-fluorobenzyl, 4-(5-methoxy-1,3-oxadiazole)-aminomethyl, 4-(5-methoxy-1,3-oxadiazole)-hydroxymethyl, 4-(5-methoxy-1,3-oxadiazole)-carboxymethyl, 4-(5-methoxy-1,3-sulfadiazole)-aminomethyl, 4-(5-methoxy-1,3-sulfadiazole)-hydroxymethyl, 4-(5-methoxy-1,3-sulfadiazole)-carboxymethyl, 2-(5-chlorothienyl)-aminomethyl, 2-(5-chlorothienyl)-hydroxymethyl, 2-(5-chlorothienyl)-carboxymethyl, 3-(1,2-thiazole)-aminomethyl, 3-(1,2-thiazole)-hydroxymethyl, 3-(1,2-thiazole)-carboxymethyl, 2-(1,4-thiazolyl)-aminomethyl, 2-(1,4-thiazolyl)-hydroxymethyl, 2-(1,4-thiazolyl)-carboxymethyl, 2-benzothienylaminomethyl, 2-benzothienylhydroxymethyl, 2-benzothienylcarboxymethyl, 2-azidooctyl-3-phenyl-3-azidomethyl, .alpha.-sulfobenzyl, and .alpha.-phosphonobenzyl. Alternatively, the group ##STR7## can be a sulfonamido group such as phenylsulfonamido, ethylsulfonamido, benzylsulfonamido, 2,5-dimethylsulfonamido, 4-chlorosulfonamido, 4-chlorophenylsulfonamido, 4-methoxysulfonamido, and the like. The acyl substituents of the general formula wherein R.sub.10 and R.sub.11 are as defined below represent a preferred group of substituents because of their generally useful antibiotic activity. R.sub.10 represents hydrogen, halo, amino, guanidino, phosphono, hydroxy, tetrazolyl, carboxy, sulfo or sulfamino. R.sub.11 represents phenyl, substituted phenyl, a monocyclic heterocyclic 5- or 6-membered ring containing one or more oxygen, sulfur or nitrogen atoms in the ring, substituted heterocycles, phenylthio, heterocyclic or substituted heterocyclic thio groups; or cyano. The substituents can be halo, carboxymethyl, guanidino, guanidinomethyl, carboxamidomethyl, aminomethyl, nitro, methoxy or methyl. Examples of these preferred substituents that might be mentioned are phenacetyl, 3-bromophenylacetyl, p-aminomethylphenylacetyl, 4-carboxylmethylphenylacetyl, 4-carboxamidomethylphenylacetyl, 2-furylacetyl, 5-nitrofurylacetyl, 3-furylacetyl, 2-thienylacetyl, 5-chlorothienylacetyl, 5-methoxythienylacetyl, .alpha.-guanidino-2-thienylacetyl, 3-thienylacetyl, 4-methylthienylacetyl, 3-isothiazolylacetyl, 4-methoxyisothiazolylacetyl, 4-isothiazolylacetyl, 3-methylisothiazolylacetyl, 5-isothiazolylacetyl, 3-chloroisothiazolylacetyl, 3-methyl-1,2,5-oxadiazolylacetyl, 1,2,5-thiadiazolyl-4-acetyl, 3-methyl-1,2,5-thiadiazolyl-4-acetyl, 3-chloro-1,2,5-thiadiazolyl-4-acetyl, 3-methoxy-1,2,5-thiadiazolyl-4-acetyl, phenylthioacetyl, 4-pyridylthioacetyl, cyanoacetyl, tetrazolylacetyl, .alpha.-fluorophenylacetyl, D-phenylglycyl, 3-hydroxy-D-phenylglycyl, 2-thienylglycyl, 3-thienylglycyl, phenylmalonyl, 3-chlorophenylmalonyl, 2-thienylmalonyl, 3-thienylmalonyl, .alpha.-phosphonophenylacetyl, .alpha.-sulfaminophenylacetyl, .alpha.-hydroxyphenylacetyl, .alpha.-tetrazolylphenylacetyl and .alpha.-sulfophenylacetyl. The substituent A in formula I above can be hydrogen, hydroxy, halo, mercapto, acyloxy, acylthio, substituted hydroxy, substituted mercapto, a quaternary ammonium group, azido, amino or a N-substituted amino group. Alternatively, CH.sub.2 A can be replaced by a formyl group. Thus, CH.sub.2 A can be a halomethyl such as chloromethyl, bromomethyl or fluoromethyl. When A is a substituted hydroxy or substituted mercapto group, it can be shown by the formula where Z is oxygen or sulfur, and R.sub.5 is an acyl group; a straight chain or branched chain loweralkyl, alkenyl or alkynyl group; an aryl group; an aralkyl group; or a heterocyclic group such as heteroaryl or heteroalkyl. These groups can be unsubstituted or can be substituted by radicals such as alkyl, alkoxy, halo, cyano, carboxy, carbamoyl, azido, sulfo, amino, substituted amino, haloalkyl, carboxyalkyl, carbamoylalkyl, N-substituted carbamoylalkyl, guanidino, N-substituted guanidino, guanidoalkyl, sulfamyl, substituted sulfamyl, and the like. Representative of the groups thus represented that might be mentioned are methoxymethyl, n-propoxymethyl, methylthiomethyl, acetoxymethyl, propionyloxymethyl, benzoyloxymethyl, (p-chlorobenzoyl)oxymethyl, (p-methylbenzoyl)oxymethyl, pivaloyloxymethyl, (1-adamantyl)carboxymethyl, butanoyloxymethyl, carbamoyloxymethyl, (N-methylcarbamoyl)oxymethyl, (N-ethylcarbamoyl)oxymethyl, [N-(2-chloroethyl)carbamoyl]oxymethyl, (N-phenylcarbamoyl)oxymethyl, (N-p-sulfophenylcarbamoyl)oxymethyl, p-carboxymethylphenylcarbamoyloxymethyl, methoxycarbonyloxymethyl, isobutanoyloxymethyl, cyclobutylcarbonyloxymethyl, carbamoylthiomethyl, (ethoxythiocarbonyl)thiomethyl, (n-propoxythiocarbonyl)thiomethyl, (cyclopentanoxythiocarbonyl)thiomethyl, methylthiomethyl, N,N-diethylthiocarbamoylthiomethyl, N-methylpiperazinium-1-thiocarbonylthiomethyl, N,N-dimethylpiperazinium-1-thiocarbonylthiomethyl, 2-furoylthiomethyl, isothiouroniummethyl, (5-methyl-1,3,4-thiadiazol-2-yl)thiomethyl, p-tolylsulfonylthiomethyl, mesyloxymethyl, 1-methyl-1,2,3,4-tetrazolyl-5-thiomethyl, tosyloxymethyl, sulfamoyloxymethyl, 1-naphthoyloxymethyl, 2-furylacetoxymethyl, cinnamoyloxymethyl, p-hydroxycinnamoyloxymethyl, p-sulfocinnamoyloxymethyl and 1R:2S-epoxypropylphosphonyloxymethyl. Alternatively, when CH.sub.2 A is hyroxymethyl, the cephalosporin can also exist as the lactone which is formed by internal esterification with the carboxy group. The substituent CH.sub.2 A can also be a group of the general formula wherein Y.sub.1 represents amino or substituted amino including nitrogen heterocycles and substituted heterocyclic groups. Examples of such groups that might be mentioned are aminomethyl, acetamidomethyl, carbamoylaminomethyl, N,N-dimethylaminomethyl, N-(2-chloroethyl)aminomethyl, 5-cyanotriazol-1-ylmethyl, 4-methoxycarbonyltriazol-1-ylmethyl. When A is amino the cephalosporin compound can also exist as the lactam formed by loss of water with the adjacent carboxy group. Representative of the quaternary ammonium groups representing A that might be mentioned are pyridinium, 3-methylpyridinium, 4-methylpyridinium, 3-chloropyridinium, 3-bromopyridinium, 3-iodopyridinium, 4-carbamoylpyridinium, 4-(N-hydroxymethylcarbamoyl)pyridinium, 4-(N-carbomethoxycarbamoyl)pyridinium, 4-(N-cyanocarbamoyl)pyridinium, 4-(carboxymethyl)pyridinium, 4-(hydroxymethyl)pyridinium, 4-(trifluoromethyl)pyridinium, quinolinium, picolinium and lutidinium. The preferred groups representing A are hydrogen, halo, azido, cyano, hydroxy, alkoxy, aryloxy, aralkyloxy, heterocycleoxy, mercapto, alkylthio, arylthio, aralkylthio, heterocyclethio, amino, alkylamino, alkanoylamino, hydroxyphenyl, acylthio, acyloxy, isothiouronium, sulfamoyloxy, quaternary ammonium, a heterocyclic tertiary amine, alkylsulfonyloxy and (cis-1,2-epoxypropyl)phosphono. The heterocycles can be a 5 or 6 membered hetero ring containing one or more nitrogen, oxygen or sulfur atoms. The acyl group can be a loweralkanoyl group of 2-6 carbon atoms, carbamoyl, or thiocarbamoyl and N-alkyl or N,N-dialkyl derivatives thereof. The alkyl group of the foregoing substituents contains 1-6 carbon atoms and may be further substituted radicals such as alkoxy, halo, amino, cyano, carboxy, sulfo, and the like. The substituent R.sub.1 in formula I above can be hydroxy, mercapto or substituted hydroxy and mercapto groups; a hydrocarbyl or substituted hydrocarbyl group; cyano, or a carbonyl or thiocarbonyl containing substituent bonded by said carbonyl or thiocarbonyl radical; a nitrogen bonded group; halo; or phosphono or a substituted phosphono group. The oxy or thio substituent represented by R.sub.1 in formula I can be hydroxy or mercapto or a substituted hydroxy or mercapto group such as --XR'.sub.1 wherein X is oxygen or sulfur and R'.sub.1 is a hydrocarbyl group, preferably a straight or branched loweralkyl group of 1-6 carbon atoms, a straight or branched chain loweralkenyl or loweralkynyl group of 3-6 carbon atoms, a monocyclic aryl group such as phenyl, or an aralkyl group such as benzyl. These alkyl, alkenyl, alkynyl, aryl or aralkyl groups can be substituted with groups such as hydroxy, halo, nitro, amino, carboxy, sulfo, and the like. Other specific substituents represented by R.sub.1 that might be mentioned are groups of the formula --OCN, --SCN, --ONR.sub.3 R.sub.4, --SNR.sub.3 R.sub.4, --OAc, --SAc, --SO.sub.3 H, --SO.sub.3 R.sub.2, --SO.sub.2 NH.sub.2, OCD.sub.3, --SO.sub.2 NR.sub.3 R.sub.4, --SO.sub.2 R.sub.2, --SO.sub.2 NR.sub.3 R.sub.4, --OCOOR.sub.2, --SOR.sub.2, --OCOSR.sub.2, --OCONR.sub.3 R.sub.4, and the like wherein Ac represents an acyl group such as a loweralkanoyl, R.sub.3 and R.sub.4 represent hydrogen, loweralkyl, acyl and loweralkoxy, and R.sub.2 represents loweralkyl, haloloweralkyl, aryl, aralkyl and substituted derivatives of such groups. When R.sub.1 is hydrocarbyl or substituted hydrocarbyl it can be loweralkyl, loweralkenyl, loweralkynyl, aralkyl, cycloalkyl, a monocyclic aryl group, or a monocyclic heterocyclic group which can also be substituted with one or more groups such as halo, hydroxy, alkoxy, amino, nitro, sulfonyl, sulfamoyl, acyloxy, carbamoyloxy, carboxy, carboxamido and N-substituted carboxamido. R.sub.1 in formula I above represents cyano or a group of the general formula --CX'R" wherein X' is oxygen or sulfur, and R" is hydrogen, halo, hydroxy, mercapto, amino, substituted amino, an aliphatic radical, an aromatic radical, an aliphatic-oxy radical or an aromatic-oxy radical. Examples of these substituents that might be mentioned are --COOH, --CSSH, --COR.sub.2, --COOR.sub.2, --COSR.sub.2, --CSSR.sub.2, --CONH.sub.2, --CSNH.sub.2, --CSR.sub.2, --CONHR.sub.2, --CSNH, --CONR.sub.3 R.sub.4 and --CSNR.sub.3 R.sub.4 wherein R.sub.2 represents a straight or branched chain alkyl group of 1-6 carbon atoms and R.sub.3 and R.sub.4 represent hydrogen or R.sub.2. R.sub.1 in formula I above represents a nitrogen bonded group such as amino and substituted amino groups, nitro, azido, nitroso, isocyanoto, isothiocyanato and hydroxyamino. Specific examples of nitrogen bonded groups that might be mentioned are --NH.sub.2, --NHR.sub.2, --NHC(O).sub.n R.sub.2, --NHC(S).sub.n R.sub.2, --NR.sub.2 R.sub.3, --NHNH.sub.2, --NHNR.sub.2 R.sub.3, ##STR8## --NNR.sub.2, --NR.sub.3 OH, --NHCNHNH.sub.2, --NHCNHNR.sub.2 R.sub.3, --NO.sub.2, --NO, --NCO, N.sub.3 and --NCS, wherein R.sub.2 represents a straight or branched chain loweralkyl group of 1 to 6 carbon atoms, R.sub.3 represents R.sub.2 or hydrogen, and n represents the integer 1 or 2. The substituent R.sub.1 in formula I represents phosphono or a metal or amine salt thereof, or a substituted phosphono group of the formula ##STR9## where Y' and Z' are the same or different and represent --OR.sub.2, --NR.sub.3 R.sub.4, ##STR10## --NR.sub.2 --NR.sub.3 R.sub.4, --NR.sub.2 N.dbd.CR.sub.3 R.sub.4, ##STR11## --NC.dbd.X', --OCOR.sub.2 and --N.sub.3, where R.sub.2 represents hydrogen or a hydrocarbyl radical, R.sub.3 and R.sub.4 represent hydrogen, hydrocarbyl, alkoxy or an acyl radical, and X' represents oxygen or sulfur. In accordance with the nomenclature of cephalosporin compounds used in the art, the compound obtained by hydrolysis of cephalosporin C, which can be represented by the structural formula ##STR12## is called 7-aminocephalosporanic acid or 7-ACA. The term "decephalosporanic acid" used herein to describe certain products, pursuant to its usage in this art, represents the basic heterocyclic nucleus having the structural formula ##STR13## Thus, a compound of the formula ##STR14## is called 3-methyl-7-aminodecephalosporanic acid using this system of nomenclature. The cephalosporin compounds with which this invention is concerned are also conveniently designated as "cepham" compounds containing the basic fused-ring betalactam thiazine structure ##STR15## which is known as cepham. Thus, the cephalosporin compounds are called "cephem" referring to the basic structure with a single olefin band. For example, in this system of nomenclature cephalosporin C having the structural formula ##STR16## is named 7-(5'-aminoadipamido)-3-acetoxymethyl-3-cephem-4-carboxylic acid. In accordance with the present invention, it is now found that the new cephalosporins of this invention can be prepared by processes which can be depicted as follows ##STR17## where R', R.sub.1 and A are as defined above. In the foregoing flowsheet the starting compound is a derivative of 7-aminocephalosporanic acid (II), hereinafter also called 7-ACA, wherein the carboxy group is preferably blocked, for example by forming a suitable ester. Thus, 7-ACA or analogs thereof having a different substituent at 3 can be esterified in accordance with methods well known in this art to obtain, for example, the esters wherein R.sub.8 represents an alkyl or substituted alkyl group such as methyl, t-butyl, pivaloyloxymethyl, acetoxymethyl and the like, a haloalkyl such as trichloroethyl, an alkenyl group such as allyl, an alkynyl group such as propargyl, an aralkyl group such as benzyl, benzhydryl, o-nitrobenzyl, 3,5-dinitrobenzyl or p-methoxybenzyl, an aryl group such as phenacyl, an organicmetallic group for example a silyl group such as trimethylsily, or a stannyl group such as tributyltin, phenacyl or trichloroethoxycarbonyl. The ester (II) is converted to the corresponding 7-diazocephalosporanic acid ester or 3-CH.sub.2 A-7-diazocephalosporanic acid ester (III) by reaction with nitrite. The 7-diazo ester (III) is converted by reaction with a pseudo halogen compound or compounds, or a compound which acts as a pseudo halogen, to form intermediate product (IV) wherein X represents halogen from the group consisting of bromine, chlorine and iodine or another leaving group, and Y is a nitrogenous substituent or R.sub.1. Intermediate compound (IV) is then converted to compound (V) wherein R.sub.1 represents a substituent other than hydrogen and Z represents a nitrogenous group which is readily convertible to amino or acylamino. Compound (V) is then converted to the desired cephalosporin ester (VI) which can be reacted to obtain the corresponding cephalosporin acid or a salt thereof. Also, the substituent at position 3 of the .DELTA..sup.3 -cepham nucleus can be converted to the other substituents of the formula --CH.sub.2 A in accordance with methods known in this art and those described herein. The processes for carrying out the various steps of the foregoing flowsheet will be more readily understood from the detailed descriptions of methods which can be used to carry out these processes which follows. The starting material in the foregoing process can be 7-ACA or a 3-CH.sub.2 A-7-aminodecephalosporanic acid which is first reacted to block or protect the carboxy group. Examples of particularly suitable 3-CH.sub.2 A-7-aminodecephalosporanic acids that might be mentioned are those wherein A represents hydrogen, hydroxy, azido, halo, a tertiary amine, isothiouronium, a loweralkoxy or loweralkylthio group, an acyloxy or acylthio group, or a heterocyclic oxy or heterocyclic thio substituent. When A is halo it can be fluoro, chloro or bromo. When A represents a loweralkoxy or loweralkylthio group it may be a group such as methoxy, methylthio, tertiary butyloxy, tertiary butylthio, and the like. When A represents an acyloxy or acylthio group it may be a group such as acetoxy, benzoyloxy, cinnamoyloxy, p-sulfocinnamoyloxy, isobutyryloxy, pivaloyloxy, adamantoyloxy, carbamoyloxy, n-methylcarbamoyloxy, N-p-sulfophenylcarbamoyloxy, N-p-carboxymethylphenylcarbamoyloxy, N-chloroethylcarbamoyloxy, N,N-diethyldithiocarbamoyloxy, N,N-dimethylpiperidinodithiocarbamoyloxy, mesyloxy, sulfamoyloxy and 1R:2S-1,2-epoxypropylphosphonyloxy. When A is a heterocyclic oxy or heterocyclic thio group it may be a group such as 5-methyl-1,3,4-thiadiazolyl-2-thio and 4-carboxamido-1,3,4-thiadiazolyl-2-thio. When A represents a tertiary amine it can be pyridinium and the like. The diazotization of the 7-amino ester is carried out in accordance with processes well known in this art. Thus, it is conveniently effected in aqueous or aqueous-organic solvent medium, for example by reaction with sodium nitrite in the presence of acid or by reaction with an organic nitrite. Organic solvents suitable for carrying out this reason are those which do not contain an active hydrogen. Examples of such solvents that might be mentioned are methylene chloride, ether, benzene, toluene, chloroform, and the like. The reaction is preferably carried out at temperatures between about 0.degree. and 50.degree. C.; usually it is most conveniently effected at room temperature. The isolation of the desired diazo compound is readily accomplished in accordance with methods known in the art. Thus, in accordance with one specific embodiment of this invention, the new cephalosporins are obtained by the following processes: ##STR18## where the substituents are as defined above. In the above process the 7-diazocephalosporanic acid ester (III) is reacted with a halo azide from the group consisting of bromine, chlorine or iodine azide, preferably in the presence of a tertiary amine azide, to produce the intermediate 7-halo-7-azidocephalosporanic acid ester (VII) which on reaction with a suitable nucleophilic reagent is converted to the desired 7-R.sub.1 -7-azidocephalosporanic acid ester (VIII). This intermediate product is reduced and acylated in one step to form the substituted cephalosporanic ester (XI) which can then be cleaved to remove the blocking group and obtain the cephalosporanic acid or a salt thereof (X). Alternatively, as shown in the flowsheet, the 7-R.sub.1 -7-azidocephalosporanic acid ester (VIII) is reduced to the 7-R.sub.1 -7-aminocephalosporanic acid ester (IX) which can be acylated to produce the 7-R.sub.1 -7-acylaminocephalosporanic acid ester (XI), or the ester group of compound (IX) can be cleaved to obtain the free acid (X) which can be acylated to form the desired substituted cephalosporin or a salt thereof. The step of cleaving the blocking group is readily effected in accordance with methods known in this art. For example, an aralkyl group such as the benzyl ester is removed by reduction, a silyl ester can be removed by hydrolysis to form the free acid or a salt thereof and a benzhydryl group is readily cleaved by reaction with trifluoroacetic acid in the presence of anisole. In this process other esters which are readily cleaved to form the free acid such as trichloroethyl, phthalimidomethyl, succinimidomethyl, p-methoxybenzyl, o-nitrobenzyl, phenacyl and t-butyl and the like can be used. Also, as is discussed above, the 3-substituent on the .DELTA..sup.3 -cepham nucleus can be varied following the procedures known in this art to obtain the substituted cephalosporins of formula I. The step of producing the halo azide intermediate is carried out by reacting the diazo compound with a halo azide at a temperature between about 0.degree. and 50.degree. C. for sufficient time to complete the formation of the desired compound. The reaction is preferably carried out in a suitable organic solvent medium which is inert to the reactants. Various solvents which do not contain an active hydrogen such as methylene chloride, chloroform, benzene, toluene, ether and the like, or mixtures thereof provide suitable mediums for carrying out the reaction. Generally, it is preferred to effect the reaction in the presence of a second azide such as lithium azide or a tertiary ammonium azide, for example triethylammonium azide, since under these conditions the formation of the undesired 7-dibromo compound is avoided. The halo azide is used in an amount in slight excess of stoichemetric requirements. The amount of second azide is not critical and it is generally desirable to use an excess in order to obtain maximum yields of the desired halo azido compound under optimum conditions. After completion of the formation of the halo azide the product is recovered and can be purified further, for example by chromatography, in accordance with processes well known in this art. The next step of the process comprising the replacement of the halo substituent by a nucleophilic group is effected by reacting the halo azide with a substance capable of furnishing a group to replace the halo. This reaction is preferably carried out in the presence of a suitable non-reactant solvent such as methylene chloride, chloroform, benzene, toluene, ether, petroleum ether and the like; again it is desirable to avoid using any solvents containing an active hydrogen. Thus, in accordance with a specific embodiment of this invention, the nucleophilic displacement reagent can be an alcohol such as methanol, ethanol, phenol, benzyl alcohol, a substituted alcohol such as 2-bromoethanol, 2-methoxyethanol, glycol amide, an ester of glycolic acid and the like which results in the displacement of the halo group and the introduction of a methoxy, ethoxy, phenoxy, benzyloxy, 2-bromoethoxy, methoxy, 2-methoxyethoxy, carbonylmethoxy or esterified carbonylmethoxy substituent, respectively. The reaction is preferably carried out in the presence of a heavy metal cation such as a silver salt. When the reaction is carried out by reacting a salt of an organic acid, preferably a heavy metal salt such as a silver salt, the corresponding 7-acyloxy compound is obtained. For example, reaction of the halo azide with silver acetate, silver benzoate, silver t-butylacetate, silver phenylacetate the corresponding 7-acetoxy, 7-benzoyloxy, 7-t-butylacetoxy and the 7-phenylacetoxy intermediate compound is obtained. The acyl groups of these various acyloxy compounds can then be cleaved to obtain the corresponding 7-hydroxy compound. Alternatively, in this process of preparing the 7-acyloxy compounds the reaction can be carried out by using a salt of the appropriate acid and carrying out the reaction in the presence of a heavy metal salt such as silver oxide or silver tetrafluoroborate. In the next step of the above-described process the 7-azido-7-R.sub.1 compound is then reduced to afford the corresponding 7-amino-7-R.sub.1 compound. Various methods of carrying out this reduction can be employed, but it is generally preferred to carry out the reduction of the azido to the amino group by catalytic hydrogenation employing a noble metal catalyst such as platinum, palladium or oxides thereof. These processes are carried out in accordance with procedures well known in this art. Alternatively, the reduction can be effected in the presence of a suitable acylating agent to produce the desired 7-acylamido-7-R.sub.1 compound. The 7-amino compound can be reacted with suitable acylating agents using procedures well known in this art to obtain the desired 7-acylamido compounds. Thus, in the abovedescribed process where the substituent R is a halo group, for example chlorine, bromine or iodine, the 7-azido-7-halo compound can be reduced to the corresponding amine compound and the latter compound can then be acylated to obtain the 7-acylamino-7-halo product. Alternatively, as discussed above, the reduction and acylation steps can be combined to produce the 7-acylamido compound without separating and acylating the 7-acylamido intermediate. Those 7-amidocephalosporanate products wherein the substituent in position 7 of the cepham nucleus is bonded to the 7-carbon via a nitrogen atom are conveniently synthesized from their corresponding 7-halo-7-azido precursors. According to this method of preparation a 7-halo-7-azidocephalosporanate is converted to the corresponding 7,7-diazidocephalosporanate via treatment with an alkali metal azide and this intermediate is then subjected to reduction via hydrogenation in the presence of a suitable catalyst as, for example, a palladium-on-charcoal catalyst. The resulting 7-amino-7-azidocephalosporanate is then acylated by treatment with an acyl halide, carboxylic acid anhydride or sulfonyl halide and the 7-amido-7-azidocephalosporanate thus obtained is again subjected to reduction and then converted to the free acid by conventional means to afford the desired product. The following equation, wherein the acylating agent employed is an acyl halide, illustrates this method of preparation; however, it is to be understood that any other acylating agent can be substituted therefor in an otherwise analogous reaction to afford the desired 7-amido- or 7-sulfonamidocephalosporanic acid product: ##STR19## The 7-amido-7-aminocephalosporanic acids of this invention are intermediates which will react at the amino nitrogen atom with a wide variety of reagents to afford the N-substituted and N,N-disubstituted derivatives thereof. Thus, for example, a 7-amido-7-aminocephalosporanic acid will react with one or more equivalents of an aldehyde such as formaldehyde, acetaldehyde or propionaldehyde and the like or an aralkaldehyde such as benzaldehyde and the like to afford the corresponding 7-amido-7-N-alkyl (or aralkyl)cephalosporanic acid. In addition to the reaction with aldehydes a 7-amido-7-aminocephalosporanic acid can be treated with an acylating and sulfonating agent such as an acyl halide, carboxylic acid anhydride, alkanesulfonyl halide or pyridinesulfur trioxide complex to afford the corresponding 7-amido-7-acylamido (or 7-sulfonamido)cephalosporanic acid product. Those 7-amido-7-aminocephalosporanic acids wherein the 7-amino radical is substituted by ureido or an N,N-dialkylureido are conveniently obtained by treating the former with the appropriate carbamoyl halide or N,N-dialkylcarbamoyl halide. Similarly, the 7-amido-7-guanidinocephalosporanic acid derivatives are obtained by simply treating the 7-amido-7-aminocephalosporanic acid precursor with N-amidino-3,5-dimethylpyrazole. The 7-amido(7-amidinoureido)cephalosporanic acid derivatives are obtained by first treating the 7-amido-7-aminocephalosporanic acid precursor with phosgene to afford an intermediate which, upon treatment with guanidine, yields the desired product. Alternatively, in accordance with a further embodiment of this invention the 7-aminocephalosporins are also obtained using a benzhydryl ester of the 7-azido-7-halo compound of formula VII as the starting material. This compound is reacted with t-butyl carbamate to produce the corresponding 7-t-butylcarbonylamino compound. Reduction of this intermediate product with hydrogen in the presence of platinum oxide affords the 7-amino-7-t-butylcarbamoylaminobenzhydryl ester. The latter compound is then acylated to produce the benzhydryl-7-acylamido-7-t-butylcarbamoylamino compound which on treatment with trifluoroacetic acid in the presence of anisole affords the 7-aminocephalosporin. The 7-amido-7-phosphono compounds and the 7-amido-7-phosphinyl products of this invention and their corresponding salt and ester derivatives are obtained by treating a 7-azido-7-halocephalosporanate compound with an appropriate phosphite, phosphonamidic acid or diamidophosphorous acid in the presence of a metal salt, i.e. a silver salt such as silver oxide or silver tetrafluoroborate and the like. The 7-azido-7-phosphono (or 7-phosphinyl) compound thus obtained is then reduced to the corresponding 7-amino-7-phosphono (or 7-phosphinyl)cephalosporanate and subjected to acylation via treatment with an acyl halide, carboxylic acid anhydride or sulfinyl halide to afford the corresponding 7-amido-7-phosphono (or phosphinyl) compound and this intermediate can then be isolated and purified or, if desired, the said ester may be converted to the corresponding free acid as described above. Also, upon treatment with a base, the said acid can be converted to its corresponding 7-amido-7-phosphono (or phosphinyl) salt. When the halo azide compound is reacted with carbon dioxide or carbon disulfide in the presence of phenyllithium, the corresponding 7-azido-7-carboxy or 7-azido-7-thiocarboxy compound is obtained. These carboxy or thiocarboxy compounds can be converted to the corresponding haloformyl compound by reaction with halogenating agents pursuant to processes well known in this art. For example, the 7-carboxy-7-azido compound by reaction with thionyl chloride is converted to the 7-chloroformyl-7-azido compound which can be reduced to the 7-amino-7-chloroformyl compound and acylated to produce the desired cephalosporanic acid or decephalosporanic acid compounds. Further, the 7-haloformyl compound on reaction with an alcohol such as methanol, phenol or benzyl alcohol is converted to the corresponding 7-methoxycarbonyl, 7-phenoxycarbonyl, or 7-benzyloxycarbonyl compound. Upon reacting the 7-haloformyl compound with an amine such as dimethylamine, dibenzylamine, diphenylamine, monoethylamine, monobenzylamine, monophenylamine, phenethylamine, hydrazine or a substituted hydrazine is converted to the corresponding 7-carboxamido compound. The 7-carboxycephalosporanic and decephalosporanic acid compounds are also obtained by oxidizing the corresponding 7-formyl compounds with argentic oxide. The 7-formyl compounds are prepared by treating the 7-hydroxymethyl substituted products with phosphoric acid at pH 2-3 to obtain the 7-hydroxy compound and then oxidizing these latter products with chromium trioxide pyridine complex. The new cephalosporanic and decephalosporanic acids wherein R.sub.1 is a hydrocarbyl group are prepared by reactions shown in the following flowsheet: ##STR20## where D is a hydrocarbyl and R.sub.1 and A are as defined above. In accordance with the foregoing flowsheet, the diazocephalosporin compound is reacted with a trihydrocarbyl boron compound at low temperatures, i.e. -50.degree. C. to -100.degree. C., for sufficient time to produce the 7-dihydrocarbylboron-7-hydrocarbon intermediate (XVII). Upon reacting this intermediate with a halogen azide such as bromine azide at room temperature, the 7-hydrocarbyl-7-azido compound (XVIII) is obtained. The latter compound is then reduced catalytically, acylated and the ester group is cleaved in accordance with the procedures described above to produce the desired 7-hydrocarbyl-7-acylamidocephalosporanic or decephalosporanic acid (XIX) or a salt thereof. In carrying out the first step of this procedure, the hydrocarbyl group of the boron compound can be a loweralkyl group of 1 to 6 carbon atoms, a loweralkenyl group of 2 to 6 carbon atoms, a loweralkynyl group of 2 to 6 carbon atoms, an aralkyl group such as benzyl, or an aryl group such as phenyl. Thus, using these tri-substituted boron compounds, the corresponding 7-alkyl, alkenyl, alkynyl, aralkyl or arylcephalosporanic acid compounds are obtained. Thus, in accordance with a specific embodiment of this invention, new cephalosporins having a 7-carboxy or substituted carboxy substituent are obtained by the following processes: ##STR21## Thus, pursuant to one of the foregoing processes, the intermediate product (IV) obtained as described above is reacted with a hydrocarbyl lithium compound of the formula R.sub.10 Li where R.sub.10 represents a hydrocarbyl group such as loweralkyl or aryl, for example n-butyl lithium, to form the 7-lithium compound (XX) which is reacted with carbon dioxide to produce the 7-.alpha.-carboxy compound (XXI). This intermediate is converted to the carboxy 7-cephalosporin (XXII) using methods shown above, or the carboxy substituent can be converted to a carboxylic acid derivative such as an ester, an amide, a hydrazide, an azide or a hydroxamic acid using procedures known in the art. Alternatively, when the 7-lithium compound is reacted with carbon disulfide in place of carbon dioxide, the corresponding 7-dithiocarboxy (--CSSH) compound is obtained. The 7-cyanocephalosporins are prepared by reacting the 7-halo-7-azido intermediate of formula VII above with tetrabutylammonium cyanide to obtain the 7-cyano-7-azido compound. This intermediate product is then reduced to the 7-cyano-7-amino compound, the latter product is acylated, and the acylated ester is cleaved to obtain the desired 7-cyano-7-acylamido cephalosporin using the procedures described above. The 7-formyl cephalosporins are prepared by converting a 7-hydroxymethyl-7-acylamido-cephalosporanic acid or a corresponding 3-CH.sub.2 A decephalosporanic acid with an oxidizing agent such as pyridine-chromium trioxide to produce the 7-formyl compound. This latter cephalosporin compound is converted to the corresponding 7-carboxy product by mild oxidizing agents such as argentic oxide. The 7-halo-substituted cephalosporins of this invention are prepared by subjecting the 7-halo-7-azido intermediates of formula VII above to reduction to afford the corresponding 7-halo-7-amino compound and this intermediate is acylated to afford the corresponding 7-acylamido-7-halocephalosporin compound. The resulting ester is then cleaved and converted to its corresponding carboxylate salt by conventional means as, for example, by treatment with trifluoroacetic acid and an aqueous solution of a base. In another embodiment of this invention, the novel 7-hydrocarbyloxy and 7-hydrocarbylthiocephalosporins can be obtained by the following sequence: ##STR22## where R.sub.8 and A are the same as defined above and G represents hydrocarbyloxy or hydrocarbylthio. In accordance with the above flowsheet, the starting compound, an ester of a 7-diazo compound defined as in III above, is reacted with a hypohalite of an alcohol or a thiol, or with an alcohol in the presence of a positive halogen such as a N-halo-amide, for example, N-bromoacetamide, N-bromosuccinimide, N-bromophthalimide and the like, that react as though they were the corresponding hypohalite. The resultant 7-halo-7-hydrocarbyloxy or hydrocarbylthio ester (XXIII) is frequently a mixture of epimers at 7, which are readily separable by chromatography. However, when only one epimer is obtained, it may be equilabrated to a mixture of epimers by treatment with an inorganic halide in a polar solvent. A lithium salt of the appropriate halide in dimethylformamide is particularly useful for epimerizing these intermediates. The 7-halo-7-hydrocarbyloxy or hydrocarbylthio product can then be reacted with an azide, such as lithium azide, to form the 7-hydrocarbyloxy or hydrocarbylthio-7-azidocephalosporanate ester (XXIV). This latter compound can then be reduced either with hydrogen or an inorganic reducing agent to form the intermediate 7-hydrocarbyloxy or hydrocarbylthio-7-amino ester (XXV) (R'.dbd.H). This latter compound can be acylated to produce the substituted cephalosporin ester. Alternatively, the reduction of the azido intermediate can be done in the presence of an acylating agent to produce these esters directly. These compounds can then be converted to the desired cephalosporin of formula XXV or salts thereof in accordance with procedures described above. The various processes described above can result in the production of a particular epimer at 7, or in a mixture of epimers at 7; i.e., a 7.alpha.-halo-7.beta.-R.sub.1 or a 7.beta.-halo-7.alpha.-R.sub.1 compound. When a mixture of epimers is obtained, these can be readily separated in accordance with methods, such as chromatography, which are well known in this art. In some cases, when only one epimer is obtained it can be equilabrated to produce a mixture of epimers by procedures known in the art. Pursuant to a further embodiment of this invention, novel products are also obtained by a new process whereby the acyl group of a 7-acylamidocephalosporin compound is replaced by a different acyl substituent. In accordance with this new process, the 7-acylamidocephalosporin compound is reacted with an acylating agent to obtain an intermediate 7-diacylamidocephalosporin compound containing two different acyl substitutents, and the original acyl group is then cleaved to obtain a new 7-acylamidocephalosporin compound. This process is illustrated in the following flowsheet: ##STR23## wherein Ac represents an acyl group, A', R'.sub.1 and R.sub.p represent, respectively, substituents defined as A, R.sub.1 and R', respectively, or are reconvertible thereto by the removal of any protecting or blocking group. In the process described in the foregoing flowsheet, the reactions can be carried out with the free acid, although in general it is found preferable to block or protect the carboxy group by the formation of a suitable ester which can be readily removed at the end of the process. The first step of this process comprises reacting the cephalosporin compound, or a derivative thereof wherein the carboxyl group is blocked, with an acylating agent, preferably an acyl halide, in the presence of a silyl group to produce the 7-diacylamido compound. This product is then reacted to remove the original acyl substituent and produce the cephalosporin compound having the new 7-acylamido substituent. The first step of producing the diacylated product is best effected by intimately contacting the cephalosporin compound with an acylating agent in a suitable solvent medium in the presence of a tri-substituted silyl derivative of a negatively-substituted amide. The temperature at which the reaction is carried out is not particularly critical and temperatures from about -20.degree. C. to about 100.degree. C. are generally satisfactory, although we prefer to carry out the reaction at temperatures from about 25.degree. to 40.degree. C. Various solvents which do not contain an active hydrogen such as chloroform, acetonitrile, methylene chloride, dioxane, benzene, halobenzene, carbon tetrachloride, and diethylether are most suitable as mediums in the reaction. Various trihydrocarbylsilyl compounds in which the hydrocarbyl substituent is a loweralkyl (1 to 6 carbon atoms), an aryl such as phenyl, or an aralkyl group such as benzyl can be utilized in the process of this invention. These compounds are readily prepared by reacting equimolecular amounts of a trihydrocarbylsilyl halide with a negatively-substituted amide or imide. However, it is generally preferred to use a triloweralkylsilyl derivative, and in particular the trimethylsilyl derivative since this product is inexpensive and readily available. Negatively-substituted amides and imides that might be mentioned are succinamide, phthalimide, cyanoacetamide, trifluoroacetamide, benzamide, p-nitrobenzamide, trichloroacetamide, a sulfonamide, and the like. Examples of triloweralkylsilyl derivatives that are especially useful and might be mentioned are N-trimethylsilyltrifluoroacetamide, N-trimethylsilylphthalamide. Generally, it is preferred to carry out the foregoing reactions with a cephalosporin compound wherein the carboxy group is blocked or protected since maximum yields of the desired product are obtained with such derivatives. For this purpose, the carboxy substituent is blocked by forming a suitable ester such as a benzyl, benzhydryl, p-nitrophenyl, trimethylsilyl, trichloroethoxy, p-methoxybenzyl, phthalimidomethyl, or succinimidomethyl ester which are readily removed by processes well known in this art. In addition, it is generally preferred to block or protect any amino groups present in the starting cephalosporin compound since maximum yields of the desired products are obtained with such derivatives. For this purpose, the groups are preferably blocked with substituents that are readily removed. Such groups are well known in the art. For example, the amino group is most conveniently blocked by a group such as trichloroethoxycarbonyl, t-butoxycarbonyl, benzoylmethoxycarbonyl, trimethylsilyl, p-methoxybenzyloxy, o-nitrophenylthio, and the like. The step of cleaving the original acyl group can be effected in several ways, namely, by prolonging the reaction time, by the addition of an alcohol such as a loweralkanol or a loweralkylthiol, or by hydrolysis in an aqueous solution containing a small amount of an acid or a base. Thus, in some cases cleavage is effected by the addition of a loweralkanol or loweralkylthiol containing from 1 to 6 carbon atoms, an aralkanol such as benzyl alcohol, or the corresponding thiol. The cleavage affords the desired monoacylated cephalosporin compound or can also result in the production of a mixture of the monacylated compounds. In the latter case the desired monoacylated cephalosporin compound is recovered by separation procedures such as chromatography which are well known in this art. The process of this embodiment of our invention is particularly suitable for replacing the aminoadipoyl group of 7-(aminoadipoylamido) side chain of cephalosporins such as those obtained by fermentation and derivatives thereof having other substituents at the 3 position. Thus, in accordance with a specific embodiment of this process, a cephalosporin compound such as cephalosprin C or 7-(D-5'-amino-5'-carboxyvaleramido)-3-carbamoyloxymethyl-7-methoxy-3-cephe m-4-carboxylic acid or derivatives thereof, is reacted with an acylating agent in the presence of a tri-substituted silyl radical to obtain the 7-diacylamido derivative having two different acyl groups. The diacylated product can be selectively cleaved to remove the .alpha.-aminoadipoyl group and obtain the desired different 7-acylamidocephalosporin compound. Although the cephalosporin compound per se can be transesterified by our process, we have found that the process is facilitated and maximum yields of the new 7-acylamido compound are obtained under optimum conditions when the amino and the carboxy substituents of the cephalosprin compound are blocked or protected in carrying out our process. The various blocking or protecting groups mentioned above are suitable for this purpose. Thus, for example, in replacing the .alpha.-aminoadipoyl side chain of the cephalosporins mentioned above with another acyl group, pursuant to this preferred embodiment of this invention, both the carboxy group at the 4-position and the carboxy group of the aminoadipoyl substituent are blocked and the amino group is similarly protected. The resulting blocked derivative is reacted with an acylating agent, preferably an acid halide such as the chloride, in the presence of the tri-substituted silyl derivative of the negatively-substituted amide or imide to produce the 7-diacylamido derivative. During this acylation reaction some cleavage of the .alpha.-aminoadipoyl group occurs, but most of the product is obtained in the form of the diacylated derivative. When the protecting group of the amino substituent of the aminoadipoyl moiety such as a trichloroethoxycarbonyl or a t-butoxycarbonyl group, is removed by suitable means, a selective cleavage of the aminoadipoyl group occurs. This removal of the protecting group of the amino function apparently results in an internal cyclization of the aminoadipoyl group resulting in cleavage of the grup as the .alpha.-carboxylic ester of the formula ##STR24## Our present evidence indicates that this is the mechanism of this cleavage, however we do not wish to be bound by this explanation of how the cleavage occurs since subsequent studies may establish that the product is cleaved and extruded in some other manner. This explanation of how the cleavage occurs is presented to provide a better understanding of our invention. The cleavage of the protective groups on the amino and carboxy functions is accomplished in accordance with procedures well known in this art. Thus, for example, the trichloroethoxy carbonyl group is removed by reaction with zinc and acetic acid, and the t-butoxycarbonyl and benzhydryl groups are removed by reaction with trifluoroacetic acid. In accordance with a further aspect of our invention, new 7-diacylamido compounds obtained by our process are not only useful as intermediates in the preparation of monoacylated cephalosporins but are useful antimicrobial products active against various pathogenic microorganisms. A more complete understanding of the processes of this invention is provided by illustrative embodiments which follow. Thus, 7-(D-5'-amino-5'-carboxyvaleramido)-3-carbamoyloxymethyl-7-methoxy-3-cephe m-4-carboxylic acid is converted to the corresponding 7-(2-thienylacetamido) compound in accordance with the processes of the following sequence of reactions: ##STR25## In the foregoing process the starting compound is acylated by reaction with trichloroethoxycarbonyl chloride to produce the N-trichloroethoxycarbonyl derivative which, upon alkylation with diphenyldiazomethane, is converted to the dibenzhydryl ester. Reaction of the resulting cephalosporin compound with trimethylsilyltrifluoroacetamide and 2-thienylacetyl chloride affords the 7-[(D-5'-trichloroethoxycarbonylamino-5'-carboxyvaleryl)-(2-thienylacetyla mino)] compound. This aminoadipoyl group is then cleaved by reaction with zinc in the presence of acid to obtain the benzhydryl ester of 3-carbamoyloxymethyl-7-(2-thienylacetamidodecephalosporanic acid, which is further deblocked to remove the benzhydryl group and form the free acid. This product can be converted to a salt in accordance with methods known in the art. Other acylating agents such as those defined in R.sub.1 above can be used in place of the 2-thienylacetylchloride shown in the foregoing flowsheet to produce the corresponding 7-acylamido cephem compounds. In using such acylating agents it is necessary to avoid the use of acylating agents containing substituents which would be affected during the reactions. Thus, amino, carboxy or hydroxy substituents of the acylating agent should be blocked or protected by groups such as those mentioned above and then subsequently removed. Examples of other specific acylating agents that might be mentioned are phenylacetylchloride, 2-furylacetylchloride, thiophenoxyacetylchloride, .alpha.-azidophenylacetylchloride, and the like. Alternatively, other acylating agents such as the anhydrides or mixed anhydrides can be utilized in place of the acid halides. This method of transacylation is indeed a valuable advance in this art since it provides a means of preparing cephalosporins containing different 7-acylamido substituents in place of the aminoadipoylamide group and thereby avoids the need for first converting known cephalosporins to the corresponding 7-aminocehalosporanic acid compound and then acylating this product. In addition to using cephalosporins produced by fermentation as starting materials in this process, derivatives of such cephalosporins containing other substituents at 3 in place of the carbamoyloxymethyl or the acetoxymethyl substituent such as 3-substituents of the general formula CH.sub.2 A defined above can be utilized. Alternatively, other 3-substituted cephalosporins can be prepared, for example, from the 3-acetoxymethyl-7-acylamidocephalosporins, in accordance with methods well known in this art. Thus, examples of other cephalosporins having a 7-methoxy or 7-hydrogen substituent which can be prepared by the above-described processes that might be mentioned are shown in the following table: ______________________________________ 7-acylamido substituent 3-substituent ______________________________________ ##STR26## CH.sub.3 ##STR27## ##STR28## .phi. -SCH.sub.2CONH ##STR29## ##STR30## CH.sub.2 OCONH.sub.2 ##STR31## ##STR32## CH.sub.3 (CH.sub.2).sub.3 SCH.sub.2CONH CH.sub.2 OCH.sub.3 ##STR33## ##STR34## ______________________________________ An alternative route for the preparation of the 7-R.sub.1 -7-amino compounds of formula IX above comprises reacting a 7-amino compound of formula II above with an aromatic aldehyde to form an imino adduct, treating this imino adduct with a defined reagent yielding a 7-R.sub.1 Schiff's base adduct and then regenerating the amino moiety. This process is not a part of this invention but is disclosed and claimed in a co-pending application, Great Britain Ser. No. 13008, filed Mar. 16, 1972. More specifically, this alternative route can be used to prepare compounds having the following formula: ##STR35## wherein A and R.sub.8 are as previously defined, and R.sub.1 is lower alkyl, lower alkoxy, lower alkylthio, lower alkanoyl, lower haloalkoxy, lower haloalkylthio, halo, lower haloalkyl, lower alkanoyloxy, (.alpha.-hydroxy) lower alkyl, (.alpha.-hydroxy) lower alkenyl, .beta.-substituted ethylene derivatives, allyl, benzyl, cyano, nitroso, carbamoyl, carboloweralkoxy, sulfo, sulfonoyl, loweralkylsulfo, phospho, nitro, carboxy, and dithiocarboxy. The starting material is the 7-NH.sub.2 compound of formula II above which is reacted with an aromatic aldehyde, preferably one having at least one o- or p-electronegative substituent, selected from the group consisting of nitro, methyl sulfonyl, cyano, carboxyl, derivatives, and the like. The preferred reactant is p-nitrobenzaldehyde. The starting material and the aromatic aldehyde are mixed together in approximately equimolar amounts in an inert solvent. Suitable solvents are dioxane, acetonitrile, dimethylformamide, dimethylsulfoxide, benzene, toluene, and the like. The aldehyde can be employed in a molecular excess if desired. The reaction proceeds readily at temperatures ranging from ambient to reflux temperature of the solvent. Since this condensation is an equilibrium reaction and since water is one of the products of the reaction, water is removed from active participation in further reactions by any of a number of usual methods, including azeotropic distillation, molecular sieves, or borate esters. The particular method is dependent upon the exact parameters of the reaction. The reaction is terminated by evaporation of the solvent. The imino derivative is then recovered and used in the next step. The latter involves the substitution of the R.sub.1 group at the carbon atom adjacent to the imino nitrogen. This reaction takes place in the presence of an inert solvent, such as those listed above, and in the additional presence of an organic or inorganic base. It is preferred to use organic bases, such as tertiary amines or pyridine. A specific tertiary amine which is preferred is diisopropylethylamine, although any tertiary lower alkylamine can be used. Inorganic bases, such as NaH, NaOH, KOH, carbonate, or bicarbonate salts, etc. can also be employed. For instance, the reaction can be conducted in "soft glass" which contains enough soluble inorganic base to catalyze the reaction. The specific reactant which is employed in the reaction with the imino compound to result in the chosen R.sub.1 group obviously depends on the R.sub.1 group desired. The following is of value in defining each reactant in terms of the final R.sub.1 group. ______________________________________ Reactant R.sub.1 ______________________________________ 1. lower alkyl sulfate or halide loweralkyl 2. loweralkanoyl halide loweralkanoyl 3. loweralkyl peroxide loweralkoxy 4. haloloweralkyl peroxide lowerhaloalkoxy 5. loweralkyl disulfide loweralkylthio 6. haloloweralkyl disulfide lowerhaloalkylthio 7. tertbutylhypohalite or perhalomethylhypohalite halo 8. haloloweralkane haloloweralkyl 9. loweralkanoyl peroxide loweralkanoyloxy 10. formaldehyde or loweralkyl- aldehyde (.alpha.-hydroxy)loweralkyl 11. reactive loweralkyl ketone (.alpha.-hydroxy) branched- loweralkyl 12. reactive ethylene derivatives (.beta.-substituted)ethyl 13. allyl halide allyl 14. benzyl halide benzyl 15. cyanogen bromide cyano 16. nitrosyl halide nitroso 17. carbamoyl halide carbamoyl 18. loweralkylhalo formate carboloweralkoxy 19. sulfuryl chloride sulfo 20. sulfamoylchloride sulfamoyl 21. loweralkylsulfonyl halide loweralkylsulfo 22. phosphorus oxychloride phospho 23. acetonecyanhydrinnitrate nitro 24. carbondioxide carboxy 25. carbondisulfide dithiocarboxy ______________________________________ "(.alpha.-Hydroxy)loweralkyl" is used to mean a group of the formula ##STR36## wherein R is hydrogen or alkyl having 1-6 carbon atoms. "Reactive loweralkyl ketone" is used to mean a ketone of the formula ##STR37## wherein one of R' or R" is a halogenated loweralkyl group, the halogen-substituted carbon being adjacent to the carbonyl function; or one of R' or R" is an alkyl carbonyl group. The carbonyl being adjacent to the carbonyl of the ketone; the other of R' or R" is loweralkyl. Thus, to illustrate, one type of "reactive loweralkyl ketone" is: ##STR38## wherein X is halo, X" is halo or hydrogen, and X' is halo, hydrogen, or loweralkyl; and R" is loweralkyl. The other type is ##STR39## R" is hydrogen or loweralkyl, and wherein R" is loweralkyl, haloloweralkyl, loweralkoxy, or lowerhaloalkoxy. "(.alpha.-Hydroxy)branchedloweralkyl" means a group of the formula ##STR40## wherein X, X', X", R', and R" are as defined above. "Reactive ethylene derivative" is used to mean an ethylenically unsaturated compound which is activated by the presence of one or more strong electron withdrawing groups. For example, compounds of the formula CH.sub.2 .dbd.CHY where Y is ##STR41## and the like are included. The term "(.beta.-substituted)ethyl" is employed to mean the following group wherein Y is the same as defined as above. Following the reaction between the imino compound and the reactant to form the novel 7-R' compounds, the imino moiety is regenerated to amino. This regeneration is effected by aminolysis or hydrazinolysis, in the presence of a catalytic amount of acid. Preferably, aniline hydrochloride is employed which serves both as a source of amine and acid. When hydrazine or hydrazine derivatives such as phenylhydrazine, 2,4-dinitrophenylhydrazine, and the like are used, acid is added. Other hydrazines or amines can be employed. Preferred media are the loweralkanols, such as methanol, ethanol, and the like. The usual acids or bases can be employed. For instance, hydrochloric p-toluene sulfonic acid or aniline can be used. The only limitation is that no undesired hydrolysis or ring damage occur. The 7-R.sub.1 -7-aminocephalosporanic acid and 7-R.sub.1 -7-aminodecephalosporanic acid esters of formula IX above prepared in this way can then be converted to the cephalosporin compounds following the procedures described above. The step of acylating the 7-amino compounds of formula IX above is effected by reacting the amine compound with the acyl acid in the presence of an activating agent such as dicyclohexyldiimide, with the acyl anhydride, with an acyl halide such as the acid chloride, or with an activated ester of the acid such as the p-nitrophenyl ester. In the process of reductively acylating the 7-azido compounds of formula VIII above, the reductive acylation is preferably effected in the presence of the acyl anhydride. The following examples are given for the purpose of illustration and not by way of limitation. EXAMPLE 1 A. Benzyl 7-diazocephalosporanate A mixture of 10 g. sodium nitrite, 4.5 g. benzyl 7-aminocephalosporanate p-toluenesulfonic acid salt, 300 ml. methylene chloride and 300 ml. water/ice is shaken in a separatory funnel. p-Toluenesulfonic acid monohydrate (1.6 g.) is added in three portions during 20 minutes. The separatory funnel is shaken vigorously during this time. The methylene chloride layer is separated, dried over sodium sulfate and evaporated under reduced pressure to 40 ml. B. Benzyl 7-azido-7-bromocephalosporanate To the solution of benzyl 7-diazocephalosporanate in 40 ml. of methylene chloride is added 40 ml. of nitromethane, and the resulting solution is cooled in an ice bath. To this solution is added 80 ml. of triethylammonium azide in methylene chloride prepared as described below. To this reaction mixture is then added 40 ml. of methylene chloride containing bromine azide prepared as described below with good stirring. After the gas evolution ceases, 200 ml. of 0.1 N sodium thiosulfate is added and the mixture is shaken vigorously. The organic layer is then separated and 200 ml. of water added. To this mixture is then added solid sodium bicarbonate in small portions until the aqueous phase remains at pH 7 after shaking. The organic layer is then separated, dried with magnesium sulfate and evaporated under reduced pressure to afford 4.8 g. of crude benzyl 7-azido-7-bromocephalosporanate in the form of a brown oil. The product is purified further by chromatography on 120 g. of silica gel using hexane/benzene in 1:1 and 1:3 ratio to elute the product. The fractions containing clean product are combined and evaporated to give benzyl 7-azido-7-bromocephalosporanate. IR (liq. film): 4.7.mu. (azide), 5.60.mu. (.beta.-lactam carbonyl), 5.75.mu. (esters). NMR.sub.CDCl.sbsb.3.sup.TMS (100 MHz): 2.01.delta. ##STR42## 3.42.delta. (AB, 2H, S--CH.sub.2 --), 4.68 and 4.71.delta. (singlets, C-6 hydrogens). Thin layer chromatography Rf of 0.70 on silica gel G using 1% methanol in chloroform. The solution of triethylammonium azide is prepared by mixing 6.0 g. of sodium azide, 20 ml. of water and 50 ml. of methylene chloride, cooling this reaction mixture to 0.degree. C. and adding 6 ml. of concentrated sulfuric acid. The resulting reaction mixture is allowed to stir for 10 minutes, the layers are separated and the aqueous layer washed with a small amount of methylene chloride which is added to the previously separated methylene chloride phase. After drying with calcium chloride, the methylene chloride solution is neutralized to pH 7 with triethylamine and the final volume is adjusted to 100 ml. with methylene chloride. The solution of bromine azide is prepared by cooling a mixture consisting of 26 g. of sodium azide, 80 ml. of methylene chloride and 6.4 g. of bromine to 0.degree. C., adding 20 ml. of concentrated hydrochloric acid, allowing the reaction mixture to stir in an ice bath for 3 hours, separating the organic phase, washing the aqueous phase with a small quantity of methylene chloride which is added to the separated organic phase, and adjusting the volume to 100 ml. with methylene chloride. C. Benzyl 7-azido-7-methoxycephalosporanate A solution of benzyl 7-azido-7-bromocephalosporanate in methanol is treated with one equivalent of dry silver fluoroborate. A buff colored precipitate forms rapidly. The mixture is stirred at 22.degree. C. for 23/4 hours. The solid is removed by filtration and the filtrate is evaporated to afford crude benzyl 7-azido-7-methoxycephalosporanate. The crude product is chromatographed on silica gel using 2% chloroform in benzene. The desired product has NMR.sub.CDCl.sbsb.3.sup.TMS (Partial, 100 MHz) 2.02.delta. ##STR43## 3.60.delta. (S, 3H, OCH.sub.3). IR (liq. film): strong absorption at 4.70.mu. (azide), 5.60.mu. (.beta.-lactam), 6.76.mu. (esters). Thin layer chromatography Rf of 0.65 on silica gel G with 1% methanol in chloroform. D. Benzyl 7-acetamido-7-methoxycephalosporanate A mixture of 70.5 mg. benzyl 7-azido-7-methoxycephalosporanate, 69.5 mg. of platinum oxide and 5.0 ml. acetic anhydride is hydrogenated at atmospheric pressure for 16 hours. The solvent is evaporated under reduced pressure, and the crude product is chromatographed on 12 g. silica gel using chloroform and chloroform with 1-5% methanol. Crude benzyl 7-acetamido-7-methoxycephalosporanate elutes with 1% methanol in chloroform. The product has IR (liq. film) 3.0.mu. (NH), 5.60.mu. (.beta.-lactam carbonyl). 5.75.mu. (esters), 5.93 and 6.60.mu. (amide) and no absorption at 4.7.mu. (azide). NMR.sub.CDCl.sbsb.3.sup.TMS (partial, 100 MHz): 2.01.delta. ##STR44## 2.07 and 2.10.delta. ##STR45## 3.50.delta. (singlet, OCH.sub.3), 5.20.delta. (singlet, C-6 hydrogen). Thin layer chromatography Rf of 0.40 on silica gel G with 5% methanol in chloroform. E. Potassium 7-acetamido-7-methoxycephalosporanate A solution of benzyl 7-acetamido-7-methoxycephalosporanate (25 mg.) in 3 ml. of 1:1 aqueous methanol is hydrogenated using 25 mg. of 10% Pd/C catalyst at 40 p.s.i. of hydrogen for 1 hour. The mixture is filtered and the pH of the filtrate adjusted to 8 with potassium bicarbonate. The aqueous solution is lyophilized to give potassium 7-acetamido-7-methoxycephalosporanate. EXAMPLE 2 A. Benzhydryl 7-aminocephalosporanate To a slurry of 6.8 g. (0.025 mole) of 7-aminocephalosporanic acid in 300 ml. of peroxide-free dioxane at room temperature is added with stirring 4.3 g. (0.022 mole) of p-toluenesulfonic acid monohydrate. The clear solution is concentrated in vacuo and flushed twice with dioxane. The residue is dissolved in 300 ml. of dioxane at room temperature, and a solution of 10 g. (0.05 mole) of diphenyldiazomethane in 25 ml. of dioxane is added dropwise over 15 minutes. The wine-colored solution is stirred for an additional 30 minutes, then 25 ml. MEOH is added to destroy the excess .phi..sub.2 CN.sub.2. The mixture is concentrated in vacuo and the residue partitioned between 200 cc. CH.sub.2 Cl.sub.2 and 200 ml. water containing 10 g. K.sub.2 HPO.sub.4 (pH 8.5). The organic phase is washed with water, dried over Na.sub.2 SO.sub.4 and concentrated in vacuo to yield an oil. The oil is stirred with 100 ml. of ether for 1 hour. The precipitate is filtered, washed with ether and dried to constant weight 4.7 g. (43%). m.p.=126.degree.-128.degree. C. Analysis calculated: C, 63.0; H, 5.01; N, 6.37. Found: C, 62.7; H, 5.18; N, 5.18. IR in CHCl.sub.3 is 5.6.mu. (.beta.-lactam C.dbd.O) and 5.8.mu. (ester C.dbd.O). NMR in CDCl.sub.3 is 1.85.delta. (singlet, NH.sub.2); 2.0.delta. ##STR46## 3.45.delta. (doublet, CH.sub.2 S); 4.8.delta. (singlet, CH.sub.2 OAC); 4.7.delta. (doublet, C.sub.6 H); 4.9.delta. (doublet, C.sub.7 H); 6.98.delta. ##STR47## and 7.4.delta. (singlet, phenyl). B. Benzhydryl 7-diazocephalosporanate To a stirring mixture of 1.6 g. of NaNO.sub.2, 30 ml. of water and 40 ml. of CH.sub.2 Cl.sub.2 at 0.degree. C. is added 880 mg. (0.002 mole) of ester followed by the addition of a solution of 760 mg. (0.004 mole) of p-toluenesulfonic acid in 5 ml. water over a few minutes. The mixture is stirred at 0.degree. C. for 20 minutes, then the organic phase is cut away, washed with 1.times.10 cc. ice water, dried over Na.sub.2 SO.sub.4 at 0.degree. C., filtered and concentrated in vacuo at room temperature to yield 900 mg. of a glass. IR is 4.8.mu. (strong N.dbd.N), 5.6.mu. (.beta.-lactam C.dbd.O) and 5.8.mu. (ester C-O). NMR in CDCl.sub.3 is 2.0.delta. ##STR48## 3.4.delta. (doublet, CH.sub.2 S); 4.8.delta. (singlet, CH.sub.2 OAC); 5.6.delta. (singlet, C.sub.6 H); 6.98.delta. ##STR49## and 7.4.delta. (singlet, phenyl). C. Benzhydryl 7-bromo-7-azidocephalosporanate To a solution of 900 mg. of benzhydryl 7-diazocephalosporanate in 20 ml. CH.sub.2 Cl.sub.2 and 10 ml. CH.sub.3 NO.sub.2 at 0.degree.-10.degree. C. is added all at once the Et.sub.3 N.sup.+ HN.sub.3.sup.- followed by the BrN.sub.3 solution, then 50 ml. of water is added followed by the addition of solid NaHCO.sub.3 to pH 8. The organic layer is separated and extracted with 2.times.20 ml. water, dried over Na.sub.2 SO.sub.4 and concentrated in vacuo to yield 900 mg. (83%). The NMR fits the structure. Thin layer chromatography on silica gel with CHCl.sub.3 shows a major spot at Rf 0.2. Chromatography of 900 mg. crude product on 25 g. silica gel with CHCl.sub.3 gives 400 mg. (39%) single spot material as an oil. IR in CHCl.sub.3 is 4.72.mu. (N.sub.3), 5.56.mu. (.beta.-lactam C.dbd.O) and 5.75.mu. (ester C.dbd.O). NMR in CDCl.sub.3 is 2.0.delta. ##STR50## 3.38.delta. (CH.sub.2 S); 4.7.delta. (singlet C.sub.6 HO); 4.94.delta. (CH.sub.2 -O) 6.95.delta. ##STR51## and 7.4.delta. (singlet, phenyl). Preparation of BrN.sub.3 Solution To 8 ml. of CH.sub.2 Cl.sub.2 at 0.degree. C. is added 2.66 g. (0.04 mole) of NaN.sub.3 followed by 0.65 g. (0.0042 mole) of bromine. To this stirring mixture at 0.degree. C. is added dropwise 2 ml. of concentrated hydrochloric acid. The mixture is stirred for 3 hours at 0.degree. C. The organic layer is decanted and the aqueous layer extracted with 1.times.5 ml. of CH.sub.2 Cl.sub.2. The combined organic phase is stored at -10.degree. C. Preparation of Et.sub.3 N.sub.H.sup.+ N.sub.3.sup.- Solution To a slurry of 1.5 g. of NaN.sub.3 in 5 ml. water and 10 ml. CH.sub.2 Cl.sub.2 at -10.degree. C. is added dropwise at -10.degree. C. to 0.degree. C. 4 ml. of 50% H.sub.2 SO.sub.4. The organic phase is poured off the aqueous paste, and the aqueous extract washed with 1.times.5 cc. CH.sub.2 Cl.sub.2. The combined organic phase is dried over CaCl.sub.2. The decanted HN.sub.3 solution is brought to pH 7 with Et.sub.3 N and stored at -10.degree. C. D. Benzhydryl 7-methoxy-7-azidocephalosporanate To a solution of 400 mg. (0.00072 mole) of bromoazide in 30 ml. methanol is added 150 mg. (0.0008 mole) of AgBF.sub.4. The mixture is stirred in the dark for 21/2 hours. The mixture is concentrated in vacuo and the residue taken up in 50 ml. of CH.sub.2 Cl.sub.2 filtered. The filtrate is extracted twice with saturated NaHCO.sub.3 solution, twice with water, dried over anhydrous MgSO.sub.4 and concentrated in vacuo to yield 300 mg. (83%) of crystals. m.p.=145.degree.-148.degree. C. IR in CHCl.sub.3 is 4.72.mu. (N.sub.3 band), 5.6.mu. (.beta.-lactam) and 5.75.mu. (ester C.dbd.O). NMR is 2.0.delta. ##STR52## 3.4.delta. (CH.sub.2 S); 3.6.delta. (singlet, OCH.sub.3); 4.88.delta. (singlet, C.sub.6 H); 4.9.delta. (CH.sub.2 O); 6.98.delta. (singlet, ##STR53## and 7.4.delta. (singlet, phenyl). Analysis calculated: C, 58.4; H, 4.45; N, 11.3; S, 6.5. Found: C, 58.56; H, 4.65; N, 11.30; S, 5.70. EXAMPLE 3 A. Benzhydryl 7-methoxy-7-aminocephalosporanate 1.0 g. of benzhydryl 7-azido-7-methoxycephalosporanate is dissolved in 100 ml. of dioxane. 1.0 g. of platinum oxide is added and the reaction mixture stirred under hydrogen at atmospheric pressure for 1 hour. Another 1.0 g. quantity of platinum oxide is added and the reaction mixture is again placed under hydrogen and stirred for 3 hours until the azide is completely reacted as determined by infrared analysis of aliquots. The solvent is removed under reduced pressure and the residue taken up in 50 ml. of chloroform and filtered through silica gel G in chloroform in a 60 ml. sintered glass funnel. The material is eluted with chloroform until 200 ml. of chloroform has been collected. The chloroform is removed under reduced pressure affording 0.632 g. of benzhydryl 7-methoxy-7-aminocephalosporanate, which is acylated directly without further purification. The starting compound is prepared using the procedures described in Example 1 starting with the benzhydryl ester of 7-aminocephalosporanic acid. B. Benzhydryl 7-methoxy-7-(2-thienylacetamido)cephalosporanate 0.632 g. of benzhydryl 7-methoxy-7-aminocephalosporanate is taken up in 25 ml. of methylene chloride and cooled to 0.degree. C. 0.6 ml. of 2-thienyl acetyl chloride is added dropwise over 30 seconds followed by 0.6 ml. of pyridine 60 seconds later. The reaction mixture is stirred at 0.degree. C. for 15 minutes and poured into crushed ice. The mixture is agitated and the organic layer separated and washed once with 20 ml. of water, once with 20 ml. of 5% sodium bicarbonate and once again with 20 ml. of water. The methylene chloride is dried and evaporated to dryness affording 1.417 g. of crude product. This material is placed on a column of 60 g. of silica gel under benzene and the column is eluted with benzene, taking 100 ml. fractions followed by 300 ml. of methylene chloride/benzene (1:1) in 3 fractions, and 500 ml. of methylene chloride in 5 fractions. The product is removed from the column by eluting with 400 ml. of chloroform in 4 fractions, affording 0.592 g. This material is taken up in 25 ml. of methylene chloride and stirred at room temperature with 20 ml. of a solution of 0.120 g. of sodium bicarbonate in water for 1/2 hour. The layers are separated and the organic layer washed with water, dried and evaporated to dryness, affording 0.420 g. of benzhydryl 7-methoxy-7-(2-thienylacetamido)cephalosporanate, which shows 1 spot on a thin layer chromatographic plate. IR: 3.05.mu. (NH); 5.62.mu. ##STR54## 5.75.mu. (ester C-O); 5.92.mu. ##STR55## NMR: 2.6-3.2 tau ##STR56## 4.94 tau (S, 6H); 5.05 tau g(CH.sub.2 --OAc); 6.11 tau ##STR57## 6.52 tau (S, OCH.sub.3); 6.64 tau (--CH.sub.2 --S); 7.99 tau (S, CH.sub.3 --C.dbd.O). C. Sodium 7-methoxy-7-(2-thienylacetamido)cephalosporanate 0.420 g. of benzhydryl 7-methoxy-7-(2-thienylacetamido)cephalosporanate is dissolved in 3.5 ml. of anisole and treated with 10 ml. of trifluoroacetic acid at room temperature for 10 minutes. the trifluoroacetic acid and anisole are removed under reduced pressure maintaining the temperature below 40.degree. C., and the residue is taken up in 25 ml. of chloroform and treated with 20 ml. of water containing 0.120 g. of sodium bicarbonate. The mixture is stirred for 1/2 hour at room temperature and the organic phase is separated and washed with water. The combined aqueous phase is washed twice with methylene chloride and lyophilized affording 0.382 g. of sodium 7-methoxy-7-(2-thienylacetamido)cephalosporanate as a brownish solid. IR: 5.65.mu. (.beta.-lactam), 5.91.mu. (amide carbonyl). NMR (DMSOD.sub.6): 2.65 tau (singlet) and 3.06 tau (doublet) (thienyl protons); 5.04 tau (singlet, 6H); 5.16 tau, ##STR58## 6.19 tau ##STR59## 6.65 tau (singlet, OCH.sub.3); 6.77 tau, (--S--CH.sub.2); 8.01 tau ##STR60## EXAMPLE 4 7-Methoxy-7-(2-thienylacetamido)-3-desacetoxy-3-pyridiniumcephalosporanic acid thiocyanate 0.100 g. of sodium 7-methoxy-7-(2-thienylacetamido)cephalosporanate is dissolved in 100 .mu.l of water containing 50 .mu.l of pyridine, 5 .mu.l of 85% phosphoric acid and 0.475 g. potassium thiocyanate. The reaction mixture is stirred at 60.degree. C. for 5 hours and cooled to room temperature. The reaction mixture is diluted with water to a total volume of 20 ml. and extracted 5 times with 5 ml. portions of chloroform. Chloroform is removed from the aqueous phase by evaporation under vacuum and the aqueous phase is then cooled to 0.degree. C. and acidified to pH 2. The mixture is allowed to stand at 0.degree. C. for 2 hours and the precipitated solid removed by filtration and dried to give 0.015 g. of 7-methoxy-7-(2-thienylacetamido)-3-desacetoxy-3-pyridiniumcephalosporanic acid thiocyanate as a pale yellow solid. IR: 4.83.mu. (CNS.sup.-), 5.62.mu. (.beta.-lactam). Rf 0.61 (BAW 3:1:1, on paper). EXAMPLE 5 A. Benzhydryl 7-methoxy-7-(2-thianaphthene-2-acetamido)cephalosporanate 330 mg. (1.57 mm.) of benzothiophene-2-acetyl chloride is added in 1 portion to a solution of 330 mg. (0.75 mm.) benzhydryl 7-amino-7-methoxycephalosporanate in 10 ml. of methylene chloride at 0.degree. C. 330 .mu.l of dry pyridine is added after 1 minute and the homogeneous reaction mixture stirred for 15 minutes at room temperature and poured onto 10 ml. of water. The organic layer is washed once with 3 ml. of cold aqueous 5% sodium bicarbonate and once with 3 ml. of cold water and dried over sodium sulfate. The solvent is removed in vacuo at room temperature and the crude product chromatographed on a 2.1 cm. (outside diameter) column containing 30 g. of silica gel under methylene chloride. All less polar contaminants, including the azide from the previous step, are eluted with 400 ml. of methylene chloride. The eluant is then changed to chloroform to remove the product. All fractions containing the product are combined and washed with 5% sodium bicarbonate and water. The solution is dried over sodium sulfate and evaporated to dryness in vacuo affording 301 mg. of benzhydryl 7-methoxy-7-(2-thianaphthene-2-acetamido)cephalosporanate as a gold oil. IR: 6.65.mu. (.beta.-lactam), 5.78.mu. (ester), 5.95.mu. (amide). NMR: 8.02 tau ##STR61## 6.52 tau (--OCH.sub.3), ##STR62## 2.5-3.1 tau (aromatic protons). TLC: silica gel G, 5% EtOAc/CH.sub.2 Cl.sub.2 Rf=0.37. B. Sodium 7-methoxy-7-(2-thianaphthene-2-acetamido)cephalosporanate 2.0 ml. of anisole and 5.9 ml. of trifluoroacetic acid are combined and added to 300 mg. of the benzhydryl 7-methoxy-7-(2-thianaphthene-2-acetamido)cephalosporanate, and the reaction mixture is stirred for 10 minutes at room temperature. Excess anisole and trifluoroacetic acid are removed in vacuo and residual anisole and trifluoroacetic acid are removed by placing the flask directly onto a high vacuum pump for 15 minutes. The residual dark oil is taken up in 15 ml. of a benzene/ethyl ether mixture (1:1). A small amount of insoluble gum is dissolved by the addition of 5 ml. of a 5% sodium bicarbonate solution in water. The organic layer is washed with water and the combined aqueous layers are lyophilized to give 185 mg. of sodium 7-methoxy-7-(2-thianaphthene-2-acetamido)cephalosporanate as a pale yellow powder. NMR: 6.18 tau (--CH.sub.2 CNH--), 8.13 tau (--O.dbd.C--CH.sub.3), 6.52 tau (--OCH.sub.3). EXAMPLE 6 Benzhydryl 7-amino-7-methoxycephalosporanate 500 mg. of platimum oxide is added to a solution of 500 mg. (1.07 mm.) of benzhydryl 7-azido-7-methoxycephalosporanate in 50 ml. of p-dioxane in a 250 ml. round bottom flask. The reaction vessel is placed under hydrogen at room temperature and atmospheric pressure with vigorous magnetic stirring. After 1 hour, 500 mg. of fresh platinum oxide is added and the reaction continued under the same conditions for an additional 3 hours. The dioxane is removed in vacuo at room temperature and the residue taken up in 5 ml. of chloroform. The catalyst is removed by passing the mixture through 15 g. of silica gel G packed in a sintered glass funnel. The product is eluted with 400 ml. of chloroform using a vacuum. The chloroform is evaporated in vacuo affording 300 mg. of benzhydryl 7-amino-7-methoxycephalosporanate as a yellow oil. EXAMPLE 7 A. 7-Methoxy-7-(p-guanidinophenylacetamido)cephalosporanic acid benzhydryl ester hydrochloride To a solution of 250 mg. of 7-amino-7-methoxycephalosporanic acid benzhydryl ester, dissolved in 1.5 ml. of dry dimethylformamide, is added in 1 portion with cooling and stirring 0.15 g. of p-guanidinophenyl acetyl chloride and 0.15 ml. of pyridine. The reaction mixture is stirred at 5.degree. C. for 5 minutes and at room temperature for 10 minutes. The solution is diluted with 15 ml. of methylene chloride and extracted 3 times with 15 ml. of water. The methylene chloride solution is dried and evaporated to dryness in vacuo and the residue is chromatographed through 20 g. of silica gel. Elution with chloroform, followed by an ethanol/chloroform mixture (1:1), affords 100 mg. of 7-methoxy-7-(p-guanidinophenylacetamido)cephalosporanic acid benzhydryl ester hydrochloride. Thin layer chromatography on silica gel using 1:1 ethanol/chloroform shows a single spot with a Rf of 0.6. IR: 6.5.mu. (lactam), 5.8.mu. (ester). B. 7-Methoxy-7-(p-guanidinophenylacetamido)cephalosporanic acid A solution of 88 mg. of the above ester and 0.7 ml. of anisole dissolved in 1.8 ml. of trifluoroacetic acid is kept at room temperature for 10 minutes. The solution is evaporated on the high vacuum pump for 5 minutes and the residue is triturated with ether until it solidifies. After decanting the ether, the solid is stirred with 50 ml. of water and filtered. The clear filtrate is lyophilized, affording 40 mg. of 7-methoxy-7-(p-guanidinophenylacetamido)cephalosporanic acid. Circular paper chromatography using butanol-acetic acid in water (3:1:1) shows 1 spot of Rf 0.25 which gives a positive Sakaguchi test and bioactivity against D. subtilis. IR: 5.7.mu. (ester, shoulder), 5.65.mu. (lactam). EXAMPLE 8 Sodium 7-methoxy-7-(2-furylacetamido)cephalosporanate Benzhydryl 7-methoxy-7-azidocephalosporanate, 1.00 g., is hydrogenated in 100 ml. dioxane for 1 hour with 1 g. PtO.sub.2, then for 3 more hours with another gram of PtO.sub.2. The solvent is removed in vacuo at a temperature below 30.degree. C. The residue is taken up in chloroform and filtered through a bed of about 1 inch of silica gel (thin layer chromatography grade), washing copiously with chloroform; total volume about 500 ml. Removal of the chloroform in vacuo affords benzhydryl 7-methoxy-7-aminocephalosporanate. Methylene chloride, 40 ml., is added, and then at 0.degree. C., first 0.7 ml. of furylacetyl chloride and then 1 ml. of pyridine are added. After 25 minutes of stirring at 0.degree. C. water is added and stirring continued for a few more minutes. The layers are separated and the organic portion washed successively with 1% aqueous H.sub.3 PO.sub.4, water, and saturated aqueous sodium bicarbonate. After drying the methylene chloride solution with MgSO.sub.4, filtering and evaporating the solvent, benzhydryl 7-methoxy-7-(2-furylacetamido)cephalosporanate is obtained. It is purified by chromatography on 60 g. neutral silica gel (Brinkmann's 70-325 mesh ASTM), and eluted with 4:1 chloroform-ethyl acetate. Its Rf on the column is 0.69-0.45, and on TLC in the same system is found to be 0.69-0.57, single spot. Its IR spectrum (CHCl.sub.3 solution) has bands at 3.0.mu. (N-H), 5.61.mu. (.beta.-lactam), 5.76.mu. (esters) and 5.9.mu. (amide). The NMR spectrum in CDCl.sub.3 has bands at 8.05 tau (3H, singlet, --COCH.sub.3), 6.65, 6.70 tau (2H, S--CH.sub.2 --), 6.55 tau (3H, singlet, --OCH.sub.3), 6.32 tau (2H, singlet, furyl-CH.sub.2 --), 4.85 5.05, 5.15, 5.35 tau (2H, AB qt., J=14 Hz, --CH.sub.2 OAc), 4.97 tau (1H, singlet, C.sub.6 --H), 3.72 tau (2H, m, furyl .beta.-H), 3.09 tau (1H, singlet, --CH.phi. .sub.2), 2.7 tau (6H, m, phenyl and furyl .alpha.-H). This compound, 0.57 g., is treated at 0.degree. C. for 5 minutes with 0.8 ml. anisole and 4.0 ml. trifluoroacetic acid. The TFA and anisole are removed below 30.degree. C. in vacuo, and 2 ml. more anisole is added and evaporated as before. The residue is taken up in a few ml. water containing 0.1 g. NaHCO.sub.3 and lyophilized to a powder, which is washed copiously with ether and dried to afford 0.45 g. of sodium 7-methoxy-7-(2-furylacetamido)cephalosporanate. Its IR spectrum (CHCl.sub.3 solution) has bands at ca. 3.1.mu. (broad, N-H), 5.67.mu. (.beta.-lactam), 5.75.mu. (ester), 5.92.mu. (amide) and 6.18.mu. (COONa). Its NMR spectrum in D.sub.2 O has bands at 7.92 tau (3H, --COCH.sub.3), 6.60, 6.66 tau (2H, S--CH.sub.2 --), 6.47 tau (3H, --OCH.sub.3), 6.20 tau (2H, furyl-CH.sub.2 -- ), 5.38 tau (HDO), 5.13 tau (2H, --CH.sub.2 OAc), 4.88 tau (1H, C.sub.6 --H), 3.63 tau (2H, furyl .beta.-H), 2.53 tau (1H, furyl .alpha.-H). The UV spectrum in pH 7 buffer has .lambda. max. 263 nm, E%=141. Its Rf on TLC (silica gel, acetone-AcOH 9:1) is 0.68. EXAMPLE 9 A. Benzhydryl 7-methoxy-7-tetrazolylacetamidocephalosporanate To a solution of 1.17 g. benzhydryl 7-amino-7-methoxycephalosporanate in 100 ml. methylene chloride cooled at 0.degree.-5.degree. C. in an ice bath is added 1.78 ml. of pyridine with stirring followed by a cooled solution of 1.17 g. tetrazolylacetyl chloride in 100 ml. methylene chloride. The mixture is allowed to react for 10 minutes at 0.degree.-5.degree. C. It is then shaken with 200 ml. of pH 2 phosphate buffer. The methylene chloride layer is dried and evaporated. The crude product, 1.2 g., is eluted through 48 g. of silica gel, using chloroform as an eluant. The desired product is eluted with 2% methanol/chloroform yielding 450 mg. of benzhydryl 7-methoxy-7-tetrazolylacetamidocephalosporanate. NMR: 8.0 tau (acetyl singlet), 6.53 tau (SCH.sub.2), 4.84 tau (6H, singlet), 3.0 tau (singlet, CH of benzhydryl), 2.6 tau (singlet, aromatic), 1.1 tau (tetrazole H). TLC on silica gel in 5 % methanol/chloroform Rf=0.28. B. Sodium 7-methoxy-7-tetrazolylacetamidocephalosporanate A mixture of 680 mg. of benzhydryl 7-methoxy-7-tetrazolylacetamidocephalosporanate, 4.4 ml. anisole and 12.2 ml. trifluoroacetic acid is stirred at room temperature for 8 minutes. The excess acid is evaporated under reduced pressure and the residue is flushed twice with carbon tetrachloride and then thrice with hexane. The solid residue is dissolved in ethylacetate, adjusted to pH 5.8 with sodium bicarbonate solution, extracted with water and freeze dried to yield 420 mg. of sodium 7-methoxy-7-tetrazolylacetamidocephalosporanate. UV .lambda..sub.max..sup.H.sbsp.2.sup.O 265 E% 104. EXAMPLE 10 Sodium 7-Methoxy-7-[1(1H)-tetrazolylacetamido]-3-(5-methyl-1,3,4-thiadiazolethiom ethyl)cepham-4-carboxylate A mixture of 420 mg. sodium 7-methoxy-7-tetrazolylacetamidocephalosporanate, 168 mg. 2-methyl-5-mercapto-1,3,4-thiadiazole and 16.8 ml. phosphate buffer (pH 6.4) is heated on the steam bath for 1/2 hour. The reaction mixture is adjusted to pH 4.85 and extracted with 25 ml. ethylacetate. The aqueous layer is adjusted to pH 1.8 with 2.5 N hydrochloric acid solution and extracted with ethylacetate. Ethylacetate is removed under reduced pressure and the residue is flushed thrice with ethanol to remove traces of ethylacetate. Then it is taken into ethanol and water, adjusted to pH 6.5 with sodium bicarbonate solution, treated with charcoal and filtered. Ethanol is evaporated and the aqueous layer is freeze dried to yield 210 mg. of sodium 7-methoxy-7-[1(1H)-tetrazolylacetamido]-3-(5-methyl-1,3,4-thiadiazolethiom ethyl)cepham-4-carboxylate. UV .lambda..sub.max..sup.H.sbsp.2.sup.O 273 E% 155. NMR: 7.28 tau (singlet, methyl of thiadiazole), 6.42 tau (singlet of methoxy group), 0.74 tau (singlet, tetrazole H). EXAMPLE 11 A. Benzhydryl 7-aminodesacetoxycephalosporanate To a mixture of 11.0 g. (0.0514 mole) of 7-aminodesacetoxycephalosporanic acid in 1.5 liter of water in a 5 liter 3-necked flask fitted with mechanical stirrer and dropping funnel is added 3.5 g. of boron trifluoride in 80 ml. of dioxane. The mixture is stirred for 1 hour (pH 2.2), 1.5 liter acetone is added, and the mixture is stirred for 10 minutes (pH 2.4). Diphenyldiazomethane (31.4 g., 0.162 mole) in 85 ml. acetone is added dropwise with good stirring during 4 hours, during which time the slurry becomes thinner. The mixture is filtered and the solid is air dried and washed well with chloroform to afford 3.8 g. recovered starting material. This 3.8 g. of starting material is recycled using 750 ml. water, 1.2 g. of BF.sub.3 in 30 ml. dioxane, 750 ml. of acetone and 11 g. Ph.sub.2 CN.sub.2 in 30 ml. acetone as described above. Filtrates from both reactions are evaporated under reduced pressure to remove acetone. The aqueous residues are extracted with chloroform (3.times.250 ml. and 3.times.150 ml.). Drying of the chloroform extracts with magnesium sulfate and evaporating affords about 45 g. of crude product, which is chromatographed on 125 g. silica gel using chloroform and chloroform-methanol (1-3%) mixtures as eluant. Fractions 3-8 are triturated individually with ether. Crystals are obtained from fractions 4-7: crop 1, m.p. 133.degree.-143.degree. C., 5.58 g.; crop 2, m.p. 95.degree.-125.degree. C., 0.52 g. Filtrates and adjacent fractions from above chromatography are combined and rechromatographed as before. Fractions 4-12 are triturated with ether. Fraction 9 is crystallized well to give crop 3, m.p. 133.degree.-142.degree. C., 1.47 g. Combined yield of benzhydryl 7-aminodesacetoxycephalosporanate is 7.57 g. Starting material is recovered from the aqueous phase by concentrating in vacuo to remove water and adjusting pH to 3.7. Starting material is precipitated on stirring. After filtering, washing the precipitate with water and acetone, and drying, 3.19 g. of recovered starting material is obtained. Benzhydryl 7-amino-3-desacetoxycephalosporanate, m.p. 146.degree.-150.degree. C. is characterized by IR, NMR and elemental analysis. Calculated for C.sub.21 H.sub.20 N.sub.2 O.sub.3 S: C, 66.30; H, 5.30; N, 7.36. Found: C, 66.24; H, 5.55; N, 7.07. The 7-aminodesacetoxycephalosporanic acid used as the starting material is prepared by the hydrogenolysis of 7-aminocephalosporanic acid using palladium-on-barium sulfate catalyst in accordance with procedures known in this art. B. Benzhydryl 7-azido-7-bromo-3-desacetoxycephalosporanate A mixture of 7.57 g. benzhydryl 7-aminodesacetoxycephalosporanate, 2.74 g. sodium nitrite, 14.7 ml. 2 N sulfuric acid, 400 ml. water and 400 ml. methylene chloride is stirred for 1 hour in a stoppered, ice cold flask. The layers are separated while cold. The aqueous layer is washed with methylene chloride and the combined CH.sub.2 Cl.sub.2 layers are dried with magnesium sulfate and evaporated under reduced pressure at .ltoreq.30.degree. C. to about 125 ml. of solution of the benzhydryl 7-diazocephalosporanate. During the time the above reaction mixture is stirring, triethylammonium azide and bromine azide are prepared. A mixture of 11.7 g. sodium azide, 9.7 ml. concentrated sulfuric acid diluted to 40 ml. with water, and 190 ml. of methylene chloride are stirred for 30 minutes in a closed system in an ice bath. The layers are separated while cold, and the aqueous residue is washed with 10 ml. of cold methylene chloride. The CH.sub.2 Cl.sub.2 layers are combined, dried with MgSO.sub.4 while kept in an ice bath, and divided into two equal parts. To one is added 4.9 ml. triethylamine; to the other 4.93 g. N-bromosuccinimide. Both solutions are stored in an ice bath until use. The 7-diazo compound in about 125 ml. of methylene chloride in a 500 ml. round bottomed flask protected with calcium chloride tube and stirred magnetically is cooled in a solid CO.sub.2 /acetone bath to -40.degree. C. (internal temperature). The bath temperature is kept at -40.degree. C. to -50.degree. C. during reaction. The triethylammonium azide solution is added all at once. The bromine azide solution is added during 5 minutes at -30.degree. C. to -25.degree. C. The flask is removed from the bath and allowed to come to 0.degree. C. during 20 minutes. 10 g. of disodium hydrogen phosphate in 300 ml. water is mixed with the reaction mixture and the layers separated. The methylene chloride layer is dried with magnesium sulfate and evaporated to give 10.3 g. crude product, which is chromatographed on 125 g. of silica gel using benzene as eluant. Fractions are collected when the yellow color approaches the bottom of the column: fraction 1, 3.8 g.; fraction 2, 1.3 g.; total yield=5.1 g. Both fractions crystallize immediately. An analytical sample of benzhydryl 7-azido-7-bromo-3-desacetoxycephalosporanate, m.p. 122.degree. C. is characterized by IR, NMR and elemental analysis. Calculated for C.sub.19 H.sub.17 N.sub.4 O.sub.3 S: C, 51.97; H, 3.53; N, 11.54. Found: C, 52.23; H, 3.59; N, 11.63. C. Benzhydryl 7-azido-7-methoxy-3-desacetoxycephalosporanate A solution of 5.1 g. (10.5 mmoles) of benzhydryl 7-azido-7-bromo-3-desacetoxycephalosporanate in 50 ml. methylene chloride and 200 ml. methanol is prepared. Pyridine (0.844 ml., 10.5 mmole) and 2.084 g. silver fluoroborate (10.7 mmole) in 10 ml. methanol are added and the reaction mixture is stirred at 22.degree. C. for 161/2 hours. The mixture is filtered and the filtrate is evaporated under reduced pressure. The residue is chromatographed on 125 g. of silica gel using benzene as eluant. Fraction 1 is collected when yellow color nears bottom of the column. Fractions 2-9 are combined and triturated with methanol. The methoxy azide crystallizes, m.p. 115.degree.-117.degree. C., 3.156 g. and is characterized by IR, NMR and elemental analysis. Calculated for C.sub.22 H.sub.20 N.sub.4 O.sub.4 S: C, 60.54; H, 4.62; N, 12.84. Found: C, 60.42; H, 4.36; N, 12.93. D. Benzhydryl 7 -(D-.alpha.-azidophenylacetamido)-7-methoxy-3-desacetoxycephalosporanate A mixture of 1.51 g. of benzhydryl 7-azido-7-methoxy-3-desacetoxycephalosporanate, 150 ml. dioxane and 1.5 g. platinum oxide is stirred under hydrogen for 1 hour. Another 1.5 g. catalyst is added and the mixture is hydrogenated for another hour. The reaction mixture is evaporated under diminished pressure (.ltoreq.35.degree. C.). The residue is taken up in chloroform and passed through silica gel-diatomaceous earth (1:1) in a 120 ml. sintered funnel. About 500 ml. of eluant is collected. The filtrate is evaporated and the process is repeated in a 60 ml. sintered funnel. The filtrate (about 500 ml.) is evaporated under reduced pressure and the residue is dried with nitrogen to give about 2 g. of benzhydryl 7-amino-7-methoxydesacetoxycephalosporanate. The benzhydryl 7-amino-7-methoxydesacetoxycephalosporanate is taken up in 50 ml. of methylene chloride and stirred magnetically in an ice bath. To the solution is added 1.65 g. D-.alpha.-azidophenylacetyl chloride. After 3 minutes 1.4 ml. of pyridine is added. The solution is stirred in an ice bath for 25 minutes, poured into 50 ml. ice water and the layers separated. The methylene chloride layer is washed with 40 ml. of dilute aqueous sodium bicarbonate and 50 ml. of water and dried overnight in a refrigerator with magnesium sulfate. The mixture is filtered, evaporated and dried to give 2.0 g. of product. The product is chromatographed on 100 g. of silica gel using benzene and benzene/chloroform mixtures as eluant. Fractions 16-20 (benzene/chloroform 1:3) contain the product, benzhydryl 7-(D-.alpha.-azidophenylacetamido)-7-methoxy-3-desacetoxycephalosporanate (834 mg.), which is characterized by IR and NMR. E. 7-(D-.alpha.-azidophenylacetamido)-7-methoxy-3-desacetoxycephalosporanic acid A solution of 708.4 mg. of benzhydryl 7-(D-.alpha.-azidophenylacetamido)-7-methoxy-3-desacetoxycephalosporanate in 2 ml. anisole is cooled in an ice bath and 8 ml. of trifluoroacetic acid added. The reaction solution is kept at 0.degree. C. for 10 minutes with occasional swirling. The solution is evaporated under reduced pressure and flushed and evaporated twice with anisole. The residue is taken up in 30 ml. methylene chloride and extracted with 3.times.5 ml. saturated aqueous sodium bicarbonate solution. The combined aqueous phase is washed with 2.times.5 ml. of methylene chloride and the pH adjusted to 1.8 with 2.5 N HCl and then extracted with 4.times.10 ml. ethylacetate. The extracts are dried with magnesium sulfate and evaporated under reduced pressure at .ltoreq.45.degree. C., then put directly onto a pump. The product obtained, (487.4 mg.), is characterized by IR and NMR. EXAMPLE 12 7-(D-.alpha.-aminophenylacetamido)-7-methoxy-3-desacetoxycephalosporanic acid To an ice-cooled solution of 487.4 mg. of 7-(D-.alpha.-azidophenylacetamido)-7-methoxy-3-desacetoxycephalosporanic acid in 6 ml. acetic acid and 9 ml. water is added 3.1 g. of powdered zinc. The mixture is stirred in an ice bath for 10 minutes and then filtered. The solid is washed with 40 ml. of water. The combined aqueous filtrates are saturated with hydrogen sulfide. After filtration the filtrate is lyophilized to afford 0.5 g. crude product. This crude product is dissolved in water and relyophilized twice to give 400 mg. of product, which is characterized by IR, NMR, electrophoresis mobility, reaction with ninhydrin and UV (.lambda.max. 262.5 m.mu., .epsilon.=5770). EXAMPLE 13 A. Benzhydryl 7-(D-.alpha.-azido-2-phenylacetamido)-7-methoxycephalosporanate To a solution of 1 g. of benzhydryl 7-amino-7-methoxycephalosporanate in 25 ml. of methylene chloride at 0.degree. C. is added 1.1 g. of D-.alpha.-azidophenylacetyl chloride in 15 ml. of methylene chloride followed by 1 ml. of pyridine. After 15 minutes stirring at 0.degree. C., the mixture is extracted with 2.times.5 ml. of cold water, 3.times.5 ml. of 1% aqueous phosphoric acid, 3.times.5 ml. of saturated aqueous sodium bicarbonate solution and 2.times.5 ml. of water. The methylene chloride solution is dried over magnesium sulfate, filtered, and concentrated under reduced pressure to afford 1.1 g. of benzhydryl 7-(D-.alpha.-azido-2-phenylacetamido)-7-methoxycephalosporanate in the form of an oil. This product is chromatographed on 60 g. of neutral silica gel and the product eluted with chloroform. Evaporation of the solvent affords 600 mg. of product whose Rf on the column is 0.069-0.047, and on TLC (silica gel, CHCl.sub.3) is 0.25, single spot. Its IR spectrum (CHCl.sub.3 solution) has bands at 3.0.mu. (N-H), 4.7.mu. (azide), 5.62.mu. (.beta.-lactam), 5.76.mu. (ester) and 5.88.mu. (amide). The NMR spectrum in CDCl.sub.3 has bands at 8.05 tau (3H, singlet, --COCH.sub.3), 6.65 tau (doublet, 2H, S-CH.sub.2 --), 6.55 tau (3H, singlet, --OCH.sub.3), 4.85, 5.05, 5.15, 5.35 tau (2H, AB qt., J-14 Hz, --CH.sub.2 OAc), 4.97 tau (1H, singlet, C.sub.6 -H), 4.89 tau (1H, singlet, .phi.(N.sub.3)C-H), 3.09 tau (1H, singlet, --CH.phi..sub.2), 2.65, 2.75 tau (15H, phenyls). B. 7-(D-.alpha.-azido-2-phenylacetamido)-7-methoxycephalosporanic acid The product obtained in A above (600 mg.) is treated for 5 minutes at 0.degree. C. with 1 ml. of anisole and 5 ml. of trifluoroacetic acid. The resulting reaction mixture is evaporated at 30.degree. C. at 0.1 mm. pressure and then twice treated with anisole and evaporated again. The residue so obtained is dissolved in 25 ml. of methylene chloride and extracted with 4.times.3 ml. of saturated aqueous sodium bicarbonate. The aqueous solution is washed once with 5 ml. of methylene chloride, adjusted to pH 1.8 with 5% phosphoric acid and extracted with 3.times.10 ml. of ethylacetate. The ethylacetate solution is dried with magnesium sulfate and evaporated to yield 370 mg. of 7-(D-.alpha.-azido-2-phenylacetamido)-7-methoxycephalosporanic acid. IR spectrum (CHCl.sub.3): 3-4.mu. (COOH), 4.74.mu. (azide), 5.62.mu. (.beta.-lactam), 5.75.mu. (ester), 5.85.mu. (amide), ca. 8.mu. (acid C.dbd.O). NMR spectrum(CDCl.sub.3): 7.92 tau (3H, singlet, --COCH.sub.3), 6.65 tau (2H, doublet, S-CH.sub.2 --), 6.51 tau (3H, singlet, --OCH.sub.3), 4.96 tau (2H, doublet, --CH.sub.2 OAc), 4.92 tau (1H, singlet, C.sub.6 -H), 4.83 tau (1H, singlet, .phi.(N.sub.3)C-H), 2.55 tau (5H, phenyl). C. 7-(D-.alpha.-amino-2-phenylacetamido)-7-methoxycephalosporanic acid To a solution of 620 mg. of 7-(D-.alpha.-azido-2-phenylacetamido)-7-methoxycephalosporanic acid in 6.2 ml. of acetic acid and 9 ml. of water is added 3.1 g. of powdered zinc and the solution stirred for 6 minutes at 0.degree. C. The zinc is filtered off and washed with 60 ml. of cold water. The combined filtrates are saturated at 0.degree. C. with hydrogen sulfide and through diatomaceous earth. The filtrate is washed with 3.times.50 ml. of ethylacetate and the aqueous solution is warmed under reduced pressure to remove dissolved ethylacetate and finally lyophilized to afford 480 mg. of 7-(D-.alpha.-amino-2-phenylacetamido)-7-methoxycephalosporanic acid as a white powder. This product contains 1 equivalent of acetic acid and 2 equivalents of water and 2% ammonia as the acetate or antibiotic salt. Spinco analysis shows 1.58 micromoles/mg. phenylglycine (84% of theory). TGA finds 17.8% weight loss to 110.degree. C. (99% of theory). Titration: inflections at pH 5.7 and 8.7, pH 1/2=7.0, EW 476 (theory for acetate dihydrate=515). Electrophoresis at pH 7 shows a single spot as a monoanion. Calculated for C.sub.19 H.sub.21 N.sub.3 O.sub.7.2H.sub.2 O.AcOH+2% NH.sub.3 : C, 46.2; H, 5.7; N, 8.8; S, 5.6. Found: C, 47.41; H, 4.99; N, 9.48; S, 6.36. Distillation from alkali and titration of the distillate finds 2% NH.sub.3. UV (pH 7 buffer): .lambda.max.=263, E% 116 (.epsilon.=6170). The NMR spectrum (100 MHz, D.sub.2 O) has bands at 7.65 tau (AcOH, ca. 1 equivalent), 7.61 tau (singlet, --COCH.sub.3), 6.17 tau (singlet, --OCH.sub.3), 6.02, 6.19, 6.45, 6.62 tau (AB qt., J=Hz, S-CH.sub.2 --), 2.13 tau (singlet, phenyl); HOD at 5 tau obscures the other protons. IR spectrum (Nujol): 2.8-4.5.mu. (NH.sub.3.sup.+), 5.65.mu. (.beta.-lactam), 5.85.mu. (ester), 6.2-6.3.mu. (COO.sup.-). EXAMPLE 14 A. Benzhydryl 7-(2-carboxy-2-phenylacetamido)-7-methoxycephalosporanate To a solution of 0.5 g. of benzhydryl 7-amino-7-methoxycephalosporanate in 15 ml. of methylene chloride is added the monobenzyhydryl phenylmalonyl chloride (prepared as described below) followed by 0.5 ml. of pyridine. The resulting reaction mixture is stirred for 30 minutes and then 12 ml. of water is added. The aqueous mixture is stirred for 5 minutes and the layers separated. The methylene chloride portion is washed with 2.5 N HCl, water, twice with aqueous sodium bicarbonate and saturated sodium chloride. The solvent layer is then dried over magnesium sulfate, filtered and evaporated below 25.degree. C. under reduced pressure to afford 0.695 g. of benzhydryl 7-(2-carboxy-2-phenylacetamido)-7-methoxycephalosporanate. This is chromatographed on 50 g. of neutral silica gel and eluted with chloroform to afford 400 mg. of product as a tan glass. IR: 3.03.mu. (NH), 5.62.mu. (.beta.-lactam), 5.78.mu. (ester), 5.88.mu. (amide). NMR (CCl.sub.4): 8.18 tau (3H, singlet, acetyl), 7.0 tau (2H, S-CH.sub.2 --), 6.80, 6.73 tau (3H, doublet, diastereomeric OCH.sub.3 's), 5.2 tau (4H, multiplet, --CH.sub.2 O--, C.sub.6 proton, malonyl CH), 3.17 tau (2H, CH.phi..sub.2), 2.8 tau (20H, aromatic), 2.0 tau (1H, amide NH). The monobenzhydryl phenylmalonyl chloride used above is prepared as follows: To a solution of 19.25 g. of phenylmalonic acid in 165 ml. of ethylacetate is added a solution of 25 g. of diphenyldiazomethane in 100 ml. of ethylacetate over 15 minutes at 15.degree.-20.degree. C. The solution is stirred 10 minutes more and 500 ml. of water is added, and sufficient 50% sodium hydroxide is added at 15.degree. C. to make the reaction mixture alkaline. The solvent layer of the mixture is separated, extracted twice with aqueous sodium bicarbonate solution. The combined aqueous solutions are washed twice with ethylacetate, cooled, acidified with hydrochloric acid and extracted 3 times with ethylacetate. The ethylacetate extractions are washed twice with water, once with saturated sodium chloride solution and then dried over magnesium sulfate. The solvent is then evaporated at a temperature below 25.degree. C. under reduced pressure to an oil which is crystallized from 200 ml. of 1:3 ether in petroleum ether to afford 20.9 g. of monobenzhydryl phenylmalonate, m.p. 119.5.degree.-122.degree. C. To a slurry of 0.7 g. of this monoester in 2.5 ml. of water is added 2.10 ml. of 0.962 N sodium hydroxide. The solution is stirred for 3 minutes, filtered and freeze dried to obtain the sodium salt of the monoester. To this sodium salt is added 5 ml. of benzene and the slurry is treated at 0.degree. C. with 1.5 ml. of oxalyl chloride. After 10 minutes at 0.degree. C. and 5 minutes at 25.degree. C. the mixture is evaporated at a temperature below 25.degree. C. under reduced pressure and the residue is twice concentrated from carbon tetrachloride. Under a dry atmosphere, the product in 5 ml. of carbon tetrachloride is |