2-(2-OXOAZETIDIN-1-YL)-CROTONSYREFORBINDELSER TIL BRUG SOM MELLEMPRODUKTER VED FREMSTILLING AF 7BETA-AMINO-3-CEPHEMFORBINDELSER

摘要

The invention concerns a process for the manufacture of 7 beta -amino-3-cephem-3-ol-4-carboxylic acid compounds by ring closure of esters of 2-[4-(substituted-thio)-3-acylamino-2-oxoazetidin-1-yl]-3-substituted- amino-crotonic acids and solvolysing the enamino group in the resulting 7 beta -acylamino-3-substituted-amino-cephem-4-carboxylic acid esters.