Synthesis, biochemical screening and in-silico investigations of arylsulfonamides bearing linear and cyclic tails

A small series of arylsulfonamide derivatives was designed and synthesized to study linear and cyclic inhibitors targeting human Carbonic Anhydrases (hCAs EC 4.2.1.1) as essential enzymes regulating (patho)-physiological processes. Particularly, the synthesis of these ten compounds was inspired to the well-known arylsulfonamides having flexible or constrained linkers able to maintain the two crucial moieties, anchoring zinc group and hydrophobic tail, in the optimized orientation within CA cavities of tumor-expressed isoforms hCA IX and hCA XII. The synthesized imine derivatives and related cyclic 1,3-thiazin-4-ones were screened in a stopped-flow carbon dioxide hydrase assay and proved to be effective inhibitors against hCA IX and hCA XII isoforms with K_i values ranging of 3.7–215.7 nM and 5.7–415.0 nM, respectively. Molecular docking studies of both series of arylsulfonamides were conducted to propose their binding mode within hCA IX and hCA XII active sites thus highlighting their distinct ability to occupy the two catalytic cavities. Moreover, the 4-[(3-cyanophenyl)methylidene]aminobenzene-1-sulfonamide 7 proved to reduce the cell viability of breast carcinoma (MCF-7) and colon rectal carcinoma (HCT-116) human cell lines under the fixed doses of 10 μM. These results encouraged us to continue our efforts in developing potent and efficient arylsulfonamides targeting hCA IX and hCA XII isoforms.