INTERMEDIATES FOR PREPARING OXACEPHALOSPORINS

摘要

PURPOSE:Compounds of formula I(A is amino; COB is carboxyl; X is halogen or OR [R is-CH2 CidenticalCH, -CH2COCH2 Nu (Nu is nucleophilic radical), etc.]; R' is=C(CH3)2,=0, etc.; Y is H, methoxy) , e.g. alpha-(4beta -chloro-3alphaphenylacetamido-2- oxoazetidin-1-yl)-alpha iso-propylideneacetic acid diphenymethyl.