1) The protection of the amino group of 2-(2-aminothiazol-4-yl)-2(Z)-(hydroxyimino)acetic acid ethyl ester (I) with di-tert-butyl dicarbonate, dimethylaminopyridine and NaOH gives 2-[2-(tert-butoxycarbonylamino)thiazol-4-yl]-2(Z)-(hydroxyimino)acetic acid (II), which is then treated with triphenylmethyl chloride (Tr-Cl) and K2CO3 in DMF to afford 2-[2-(tert-butoxycarbonylamino)thiazol-4-yl]-2(Z)-(triphenylmethoxyimino)acetic acid (III). The condensation of (III) with 7beta-amino-3-(methanesulfonyloxy)-3-cephem-4-carboxylic acid diphenylmethyl ester (IV) by means of phenylphosphoryl dichloride and N-methylmorpholine gives the 7beta-acetamido derivative (V), which is then condensed with 4-(acetylsulfanylmethylsulfanyl)-1-(triphenylmethyl)-1,2,3-triazole (VI) by means of NaOMe in THF/DMF/methanol to yield the fully protected compound (IX). Finally, this compound is deprotected by a treatment with AlCl3 anisole. The triazole (VI) can be obtained by reaction of the sodium salt of 1,2,3-triazole-4-thiol (VII) with thioacetic acid S-(chloromethyl)ester (VIII) in DMS followed by NH-protection with triphenylmethyl chloride.

2) The condensation of 1,2,3-triazol-4-thiol (X) with bromochloromethane by means of NaH gives 4-(chloromethylsulfanyl)-1,2,3-triazole (XI) with is treated with NaI in hot acetone to afford 4-(iodomethylsulfanyl)-1,2,3-triazole (XII). The reaction of (XII) with the silver mercaptide of the 7beta-[2-[2-(tert-butoxycarbonylamino)thiazol-4-yl]-2(Z)-(triphenylmethoxyimino)acetamido]-3-sulfanyl-3-cephem-4-carboxylic acid diphenylmethyl ester 1beta-oxide (XIII) in HMPT yields the condensation product (XV), which is then treated with PCl3 in DMF to eliminate the 1beta-oxide oxygen, affording the protected compound (XVI), which is deprotected with AlCl3 in anisole, as before.

1) The protection of the amino group of 2-(2-aminothiazol-4-yl)-2(Z)-(hydroxyimino)acetic acid ethyl ester (I) with di-tert-butyl dicarbonate, dimethylaminopyridine and NaOH gives 2-[2-(tert-butoxycarbonylamino)thiazol-4-yl]-2(Z)-(hydroxyimino)acetic acid (II), which is then treated with triphenylmethyl chloride (Tr-Cl) and K2CO3 in DMF to afford 2-[2-(tert-butoxycarbonylamino)thiazol-4-yl]-2(Z)-(triphenylmethoxyimino)acetic acid (III). The condensation of (III) with 7beta-amino-3-(methanesulfonyloxy)-3-cephem-4-carboxylic acid diphenylmethyl ester (IV) by means of phenylphosphoryl dichloride and N-methylmorpholine gives the 7beta-acetamido derivative (V), which is then condensed with 4-(acetylsulfanylmethylsulfanyl)-1-(triphenylmethyl)-1,2,3-triazole (VI) by means of NaOMe in THF/DMF/methanol to yield the fully protected compound (IX). Finally, this compound is deprotected by a treatment with AlCl3 anisole. The triazole (VI) can be obtained by reaction of the sodium salt of 1,2,3-triazole-4-thiol (VII) with thioacetic acid S-(chloromethyl)ester (VIII) in DMS followed by NH-protection with triphenylmethyl chloride.

1) The protection of the amino group of 2-(2-aminothiazol-4-yl)-2(Z)-(hydroxyimino)acetic acid ethyl ester (I) with di-tert-butyl dicarbonate, dimethylaminopyridine and NaOH gives 2-[2-(tert-butoxycarbonylamino)thiazol-4-yl]-2(Z)-(hydroxyimino)acetic acid (II), which is then treated with triphenylmethyl chloride (Tr-Cl) and K2CO3 in DMF to afford 2-[2-(tert-butoxycarbonylamino)thiazol-4-yl]-2(Z)-(triphenylmethoxyimino)acetic acid (III). The condensation of (III) with 7beta-amino-3-(methanesulfonyloxy)-3-cephem-4-carboxylic acid diphenylmethyl ester (IV) by means of phenylphosphoryl dichloride and N-methylmorpholine gives the 7beta-acetamido derivative (V), which is then condensed with 4-(acetylsulfanylmethylsulfanyl)-1-(triphenylmethyl)-1,2,3-triazole (VI) by means of NaOMe in THF/DMF/methanol to yield the fully protected compound (IX). Finally, this compound is deprotected by a treatment with AlCl3 anisole. The triazole (VI) can be obtained by reaction of the sodium salt of 1,2,3-triazole-4-thiol (VII) with thioacetic acid S-(chloromethyl)ester (VIII) in DMS followed by NH-protection with triphenylmethyl chloride.

1) The protection of the amino group of 2-(2-aminothiazol-4-yl)-2(Z)-(hydroxyimino)acetic acid ethyl ester (I) with di-tert-butyl dicarbonate, dimethylaminopyridine and NaOH gives 2-[2-(tert-butoxycarbonylamino)thiazol-4-yl]-2(Z)-(hydroxyimino)acetic acid (II), which is then treated with triphenylmethyl chloride (Tr-Cl) and K2CO3 in DMF to afford 2-[2-(tert-butoxycarbonylamino)thiazol-4-yl]-2(Z)-(triphenylmethoxyimino)acetic acid (III). The condensation of (III) with 7beta-amino-3-(methanesulfonyloxy)-3-cephem-4-carboxylic acid diphenylmethyl ester (IV) by means of phenylphosphoryl dichloride and N-methylmorpholine gives the 7beta-acetamido derivative (V), which is then condensed with 4-(acetylsulfanylmethylsulfanyl)-1-(triphenylmethyl)-1,2,3-triazole (VI) by means of NaOMe in THF/DMF/methanol to yield the fully protected compound (IX). Finally, this compound is deprotected by a treatment with AlCl3 anisole. The triazole (VI) can be obtained by reaction of the sodium salt of 1,2,3-triazole-4-thiol (VII) with thioacetic acid S-(chloromethyl)ester (VIII) in DMS followed by NH-protection with triphenylmethyl chloride.

2) The condensation of 1,2,3-triazol-4-thiol (X) with bromochloromethane by means of NaH gives 4-(chloromethylsulfanyl)-1,2,3-triazole (XI) with is treated with NaI in hot acetone to afford 4-(iodomethylsulfanyl)-1,2,3-triazole (XII). The reaction of (XII) with the silver mercaptide of the 7beta-[2-[2-(tert-butoxycarbonylamino)thiazol-4-yl]-2(Z)-(triphenylmethoxyimino)acetamido]-3-sulfanyl-3-cephem-4-carboxylic acid diphenylmethyl ester 1beta-oxide (XIII) in HMPT yields the condensation product (XV), which is then treated with PCl3 in DMF to eliminate the 1beta-oxide oxygen, affording the protected compound (XVI), which is deprotected with AlCl3 in anisole, as before.