The treatment of 7-ACA with 4-substituted benzensulfonyl chlorides afforded the compounds containing 4-nitro/aminophenyl sulfonylamino moiety in the cephalosporanic acid skeleton (2, 4). The synthesis of the cephalosporanic acid derivatives containing 1,3-thiazole or 5-oxo-1,3-thiazolidine nucleus and sulfonamide function (8a, 8b, 10) was performed starting from 7-ACA by several steps. The reaction of 7-ACA with [4-(2-fluoro-4-nitrophenyl)piperazin-1-yl]acetyl chloride afforded the corresponding 7-{[4-(2-fluoro-4-nitrophenyl)piperazin-1-yl]acetyl}amino derivative (13). The synthesized compounds were screened for their antimicrobial and antiurease activities. Some of them were found to possess good-moderate antimicrobial activity against the test microorganisms. Compound 5d was observed to have moderate anti-urease activity.