Objective: In this study, a new series of 5-bromoisatin derivative clubbed with pyrimidine i.e. 3-[4-(2-Amino-6substituted-phenyl-pyrimidine-4-yl)-phenylamino]-5-bromo-1, 3-dihydro-indol-2-one derivative were synthesized. Material and Methods: The reaction of 5-bromoisatin and 4-aminoacetophenone in ethanol yielded Schiff bases (1). These on further reaction with different aromatic aldehyde resulted in synthesis of chalcones (2a-2o) derivatives of 5bromoisatin. In the subsequent step reaction

more »

... chalcones with guanidine hydrochloride yielded pyrimidine derivatives (3a-3o) of 5-bromoisatin derivative. The structures of compounds were confirmed by their physicochemical and 1 spectral means (IR and HNMR). The synthesized compounds were evaluated in vitro for antimicrobial activity by tube dilution method. Minimum inhibitory concentration (MIC) of compounds were determined against S. aureus, B. subtilis (Gram positive), and P. aeruginosa, E. coli (Gram negative) bacteria and C. albican and A. niger fungal strain. Results: Although several compounds showed antimicrobial activity, moreover, compound 3g, 3h and 3i showed significant activity. Conclusion: Compound substituted with -NO , -Cl and -Br showed significant antimicrobial 2 activity.