Efficient synthesis, biological evaluation, and docking study of isatin based derivatives as caspase inhibitors

ABTRACT In this paper, a new series of isatin-sulphonamide based derivatives were designed, synthesised and evaluated as caspase inhibitors. The compounds containing 1-(pyrrolidinyl)sulphonyl and 2-(phenoxymethyl)pyrrolidin-1-yl)sulphonyl substitution at C5 position of isatin core exhibited better results compared to unsubstituted derivatives. According to the results of caspase inhibitory activity, compound20dshowed moderate inhibitory activity against caspase-3 and -7in vitrocompared to Ac-DEVD-CHO (IC50= 0.016 +/- 0.002 mu M). Among the studied compounds, some active inhibitors with IC(50s)in the range of 2.33-116.91 mu M were identified. The activity of compound20dwas rationalised by the molecular modelling studies exhibiting the additional van der Waals interaction of N-phenylacetamide substitution along with efficacious T-shaped pi-pi and pi-cation interactions. The introduction of compound20dwith good caspase inhibitory activity will help researchers to find more potent agents.