AZETIDINONE DERIVATIVES USEFUL IN THE PREPARATION OF CARBAPENEM ANTIBIOTICS

摘要

Compounds of formula (I): (I) ¢wherein: R1 is hydrogen or a hydroxy-protecting group; R2 is alkyl, alkoxy, halogen, optionally substituted phenyl or optionally substituted phenoxy; R3 is optionally substituted pyridyl, optionally substituted quinolyl or phenyl group which has a substituent of formula -CYNR5R6, where Y is oxygen or sulfur, and R5 and R6 are each alkyl, aryl or aralkyl, or R5 and R6 and the nitrogen to which they are attached together form a heterocyclic group; R4 is hydrogen or an amino-protecting group; and Z is sulfur or oxygen!; are valuable intermediates in the preparation of carbapenem compounds and retain a desirable configuration during conversion to such carbapenem compounds.