Synthesis of 1,4-bis(indolin-1-ylmethyl)benzene derivatives and their structure-activity relationships for the interaction of human carbonic anhydrase isoforms I and II.

Several 1,4-bis(indolin-1-ylmethyl)benzene-based compounds containing substituents such as five, six and seven cyclic derivatives on indeno part (9a–c) were prepared and tested against two members of the pH regulatory enzyme family, carbonic anhydrase (CA). The inhibitory potencies of the compounds at the human isoforms hCA I and hCA II targets were analyzed and KI values were calculated. KI values of compounds for hCA I and hCA II human isozymes were measured in the range of 39.3–42.6μM and 0.17–0.29μM, respectively. The structurally related compound indole was also tested in order to understand the structure–activity relationship. Most of the compounds showed good CA inhibitory efficacy. In silico docking studies of these derivatives within hCA I and II were also carried out and results are supported the kinetic assays.