Synthesis and microbial activity of novel 3-methyl-2-pyrazolin-5-one derivatives

Abstract

2-Oxo-2H-chromene-3-carbohydrazide derivatives 2a,b react with 2-{[4-(substituted thiazol-2-yl)iminoethyl)-phenyl]hydrazono}-3-oxo-butyric acid ethyl esters 4a-c to give 3-methyl-1-[(2-oxo-2H-chromen-3-yl) carbonyl]-4-{[4-(substituted thiazol-2-yl)iminoethyl)-phenyl]hydrazono}]-2- pyrazolin-5-one derivatives 5a-f. A considerable increase in the reaction rate had been observed with better yield using microwave irradiation for the synthesis of compounds 2a, b, 3a-c, and 5a-f. The synthesized products were tested against B. subtilis, S. aureus, and E. coli as well as C. albicans compared with tetracycline and nystatin as reference drugs. © 2013 Mohamed S. Mostafa et al.