| 摘要 |
Novel syn isomers of 7-(2-amino-4-thiazolyl)-acetamido-cephalosporanic acid compounds of the formula <IMAGE> I wherein R is selected from the group consisting of -(CH2)n-S-R2, -CHF2 and -(CH2)n-S-CN, R2 is selected from the group consisting of optionally protonated <IMAGE> n is an integer from 1 to 4, R1 is selected from the group consisting of hydrogen, chlorine, methoxy, alkyl and alkylthio of 1 to 5 carbon atoms, cycloalkyl of 3 to 5 carbon atoms, azidomethyl, acetoxymethyl, carbamoyloxymethyl, <IMAGE> and -CH2-S-R', Alk is alkyl of 1 to 4 carbon atoms, R' is selected from the group consisting of an optionally substituted nitrogen containing heterocycle and an acyl of an aliphatic acid of 2 to 4 carbon atoms, A is selected from the group consisting of hydrogen and an easily cleavable ester and when R is -(CH2)n-SR2, the COOA group may be the anion -COO-and when R is -(CH2)n-SCN or -CHF2, A may further be selected from the group consisting of an equivalent of an alkali metal, an alkaline earth metal, magnesium, -NH4 and a non-toxic, pharmaceutically acceptable organic amine and their non-toxic, pharmaceutically acceptable acid addition salts having antibiotic properties and a novel process and novel intermediates for their preparation. |
