SYNTHESIS AND STRUCTURE-ACTIVITY-RELATIONSHIPS OF SOME 2,5-DISUBSTITUTED BENZOXAZOLES AND BENZIMIDAZOLES AS ANTIMICROBIAL AGENTS

The synthesis of a new series of 2,5-disubstitutedbenzoxazoles 5a-e, a nd 2,5-disubstitutedbenzimidazoles 6a-h are described in order to dete rmine their antimicrobial activities and feasible structure-activity r elationships (SAR). The synthesized compounds were tested in vitro aga inst 3 Gram-positive, 3 Gram-negative, bacteria and a fungus Candida a lbicans. 5c, and 5e were found most active than the others against Bac illus subtilis at a MIC value of 3.12 mu g/ml and the compounds 5e, 6a and 6e indicated significant antibacterial activity against the enter obacter Pseudomonas aeruginosae. 5a, 5c, 5d and 6d also exhibited anti mycotic activity against C. albicans. The antibacterial and antimycoti c activities of 5-6 are compared with several control drugs.