The Preparation, Isolation, and Identify for the Isomers of Cefotiam Hexetil

The derivative of ceoftiam hexetil, which include a pair of isomers (the ratio of the isomers 1:1), was prepared and identified in this article. Two ?-3 isomers were separated by MCI-GEL CHP20P resin, and their structures were identified by NHR and HPLC. The ratio of the two isomers was calculated nearly 1:1, corresponded to the theoretical data. The ?-2 ceoftiam hexetil, which is side product of esterification, was monitored by HPLC and prepared. The esterification condition was optimized and the esterification product -- ceoftiam hexetil accorded with the Japanese Pharmacopoeia.