Abstract
Cefodizime sodium (CDZM, THR-221) is a new semi-synthetic cephalosporin. The acidic degradation of cefodizime and structural elucidation of the degradation products were investigated. In acidic solution, cefodizime was converted to the anti-form of cefodizime [THR-221-A] and the Δ3-cephem form [THR-221-B]. In another degradation pathway, cefodizime was degraded to desacetyl cefotaxime [THR-221-I] and mercaptothiazole [THR-221-IV]. THR-221-I was further changed to desacetyl cefotaxime lactone [THR-221-IIa] and its anti-form [THR-221-IIb], two isomers of deslactam desacetyl cefotaxime lactone [THR-221-III and -III'], deslactam descarboxy desacetyl cefotaxime lactone [THR-221-IVa] and its anti-form [THR-221-IVb] and methoxyimino-aminothiazolyl aldehyde [THR-221-V].Based on the structural elucidation, the acidic degradation pathways of cefodizime were determined.
