Reference

Studies on condensed-heterocyclic azolium cephalosporins

Studies on condensed-heterocyclic azolium cephalosporins. II. Synthesis and antibacterial activity of 7b-[2-(2-aminothiazol-4-yl)-2(Z)-alkoxyiminoacetamido]-3-(condensed- heterocyclic azolium)methyl-3-cephem-4-carboxylates. Yoshimura, Yoshinobu; Miyake, Akio; Nishimura, Tatsuo; Kawai, Tatsuhiko; Yamaoka, Masayoshi (Res. Dev. Div., Takeda Chem. Ind., Ltd., Osaka 532, Japan). J. Antibiot., 44(12), 1394-405 (English) 1991. CODEN: JANTAJ. ISSN: 0021-8820. DOCUMENT TYPE: Journal CA Section: 26 (Biomolecules and Their Synthetic Analogs) Section cross-reference(s): 10 7b-[2-(2-Aminothiazol-4-yl)-2(Z)-alkoxyiminoacetmido]cephalosporins contg. imidazo[1,5-a]pyridinium-, imidazo[1,2-b]pyridazinium-, imidazo[1,2-a]pyrimidinium-, imidazo[1,2-c]pyrimidinium-, and pyrazolo[1,5-a]pyridiniummethyl groups at the 3 position were prepd. Among the cephalosporins tested, the antibacterial activity of cephalosporins I (R+ = imidazo[1,5-a]pyridinium, pyrazolo[1,5-a]pyridinium and imidazo[1,2-b]pyridazinium) was superior to that of ceftazidime. These results imply that the delocalization of the pos. 6775-78-6 and 103358-42-5 are just another two chemicals used in this study. charge of these groups leads to an expanded antibacterial spectrum and increased activity and that these condensed-heterocyclic compds. as well as imidazo[1,2-a]pyridine are effective moieties for improving antibacterial activity and spectrum. .