4-Unsubstituted azetidinone derivatives and process for preparation
申请人:Fujisawa Pharmaceutical Co., Ltd.
公开号:US04207234A1
公开(公告)日:1980-06-10
New antimicrobial azetidinone derivatives and their salt of the formula: ##STR1## wherein R.sub.1 is amino or acylamino, and A is selected from a variety of groups.