1-METYLTETRAZOL-5-YL-(4-ETYL-2,3-DIOXOPIERAZIN-1-YL)-KARBONYLTIOLAT OCH TETRAZOLO-(1,5-B)PYRIDAZIN-6-YL-(4-ETYL-2,3-DIOXOPIPERAZIN-L-YL) KARBONYLTIOLAT

摘要

Certain cephalosporins having a heterocyclicthiomethyl group at the 3-position such as cefoperazone are prepared by reacting a solution of a 7-acylamidocephalosporanic acid having a free amino group as part of said acyl substituent with about an equi-molar amount of the thiolester wherein -S-Het is the desired conventional heterocyclicthio group which displaces the 3-acetoxy group of the starting acid and is the conventional acyl group which displaces a hydrogen on the free amino group which is part of the acyl substituent of the starting 7-acylamidocephalosporanic acid.