OXAZOLINOAZETIDINYLSMORSYRADERIVAT

摘要

Intermediates (I) for preparing a potent antibacterial, 1-oxadethiacephalosporin, are shown by the following formula (wherein R is a group of acyl-minus-carbonyl derived from a carboxylic or carbonic acid; COB is carboxy or protected carboxy; X is hydrogen or a nucleophilic group; Y is a nucleophilic group; and Z is a leaving group) and prepared from the corresponding exomethylene compound (II) by addition of a compound of formula: Y-Z (in which Y and Z are as defined above).