A few derivatives of 3-(4,5-dihydro-5-aryl-1-phenyl-1H-pyrazol-3-yl)-4- hydroxyquinolin-2(1H)-ones (5a–j) that are synthesized from 4-hydroxy-3-(3- arylacryloyl)quinolin-2(1H)-ones (4a–j) by microwave-assisted synthesis are screened for their antimicrobial, in silico antimalarial activities. Among the tested compounds 4h and 5d were found to have a potent antimalarial activity than the standards, and the others are found to show considerable antimalarial activity and moderate antimicrobial activity. © Springer Science+Business Media New York 2014.