CL 118523 is an aminothiazolyl cephalosporin which contains a 1, 2, 3-thiadiazol radical at position 3 of the cephem nucleus. It was as active as cefotaxime, ceftazidime and aztreonam against most Enterobacteriaceae, MIC 90% less than 1 mg/l, and more active, 8 to 32-fold, than cefoperazone and cefoxitin.
