1-OXADETHIACEPHAM COMPOUNDS

摘要

1-Oxadethiacepham Compounds Intermediates for preparing an antibacterial 1-dethia-1-oxa-cephalosporins which are represented by the following formula: (wherein R is a monovalent group deducted the carbonyl from an acyl derived from a carboxylic or carbonic acid; Y1 is a divalent group of the following formula: , , , or (in which COB is carboxy or protected carboxy; X is hydrogen or a nucleophilic group; and Z is a leaving group) are prepared from a compound of the following formula: (wherein R and Y1 are as defined above) by the action of an acid. The new compounds of this invention shown by the following formula: (wherein A is amino or substituted amino; E is hydrogen or methoxy; and Y is a divalent group of the following formula: , , , or (in which COB, X, and Z are as defined above) are convertible into other compounds of the same formula by applying conventional methods in .beta.-lactam chemistry.