Discovery of a novel series of indolylchalcone-benzenesulfonamide hybrids acting as selective carbonic anhydrase II inhibitors

The primary sulfonamide group is one of the most efficient zinc binding group (ZBG) for designing carbonic anhydrase (CA, EC 4.2.1.1) inhibitors. In the present study primary sulfonamide linked with indolylchalcone were designed. The newly synthesized molecules (5a-r) were examined against four human (h) CA isoforms (hCA I, hCA II, hCA IX and hCA XIII). These sulfonamides showed good inhibition activity against isoforms hCA I, hCA II and hCA XIII. Compound 5i (2.3 nM), 5m (2.4 nM), 5o (3.6 nM) and 5q (7.0 nM) were more potent than standard drug AAZ (12.1 nM) against isoform hCA II, respectively. Most of the other compounds in the present series inhibited hCA XIII and hCA IX in the range of 50 nM − 100 nM.