The inhibitory effect of newly synthesized C- (anthranyl and biphenyl)-5-substituted-I´2-isoxazolines were characterized by IR, 1H NMR, 13C NMR and CHN anal. and evaluated for their antimicrobial activity against different strains. Strains such as Bacillus subtilis, Escherichia coli, Pseudomonas fluorescens, Xanthomonas campestris pvs., Xanthomonas oryzae, Aspergillus niger, Aspergillus flavus, Fusarium oxysporum, Trichoderma species and Fusarium moniliforme were examnd. Among the newly synthesized compds., Et and Bu 3-biphenyl-4-yl-4,5-dihydroisoxazole-5-carboxylate and 3-biphenyl-4-yl-4,5-dihydroisoxazole-5-methanol showed significant inhibitor activity. [on SciFinder(R)]