α-Chymotrypsin inhibitors of thiourea class are reported that could be potent inhibitors of proteases, elastases, proteasomes, NS3 and NS4 serine protease of hepatitis C virus, dengue virus, etc. Compounds
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which are belong to thiourea class, showed good inhibition. Their kinetics study and cytotoxicity profiles showed all type of inhibition except uncompetitive-type inhibition and no cytotoxicity except few compounds. Competitive type of inhibitors could inhibit other α-chymotrypsin-like serine proteases, which are therapeutics target.