| 摘要 |
<p>7-amino- .DELTA. 3-cephem-4-carboxylic acid esters of the general formula I wherein R1 represents a five-membered heterocyclic ring containing one or two nitrogen atoms and one oxygen or sulfur atom, or is a fivemembered heterocyclic ring containing three or four nitrogen atoms, or is a six-membered heterocyclic ring containing one to three nitrogen atoms and one sulfur atom , or is one of the aforementioned heterocyclic rings substituted by linear or branched C1-C8 alkyl, phenyl, C1-C4 alkoxyphenyl, nitrophenyl, or chlorophenyl or wherein R1 is one of the aforementioned unsubstituted or substituted heterocyclic rings annellated to a benzene ring, and R2 stands for optionally substituted linear or branched alkyl, cycloalkyl, aryl, aralkyl, aryloxyalkyl, alkoxyalkyl, acyloxyalkyl, aroylalkyl or a heterocyclic radical, and salts of these esters and a process for their manufacture.</p> |
