A series of urea/thiourea derivatives were synthesized by using peptides conjugated to 3-(1-piperazinyl)-1,2-benzisothiazole and their structure was characterized by analytical and spectral ((1)H, (13)C NMR and Mass) methods. These compounds were screened for antimicrobial and antiglycating activity as well as urease and H(+)/K(+)-ATPase inhibition. Preliminary structure-activity relationship studies revealed that the compounds possessing fluoro moiety were excellent antimicrobial agents. Furthermore, for other biological activities methoxy substituent was found to be the most active particularly upon substitution at para position.