PROCESS FOR THE PREPARATION OF CEPHEMS

摘要

The invention provides both a process for the preparation of compounds represented by the general formula (I), pharmaceutically acceptable salts thereof, or solvates of both: (I) [wherein R<1> and R<2> are each independently optionally substituted lower alkyl], characterized by deblocking a compound represented by the general formula (II), a pharmaceutically acceptable salt thereof, or a solvate of either: (II) [wherein R<1> and R<2> are each as defined above; R<3> is an amino-protecting group; and R is an anion, hydrogen, or a carboxyl-protecting group]; and crystals of compounds (II).