Novel benzenesulfonamide derivatives as potential selective carbonic anhydrase IX, XII inhibitors with...

As inhibitors of carbonic anhydrases (CAs) IX and XII, a novel series of 1,2,3-triazole benzenesulfonamide derivatives 17a-l containing pyrazolyl-thiazole moiety was designed, synthesized, and tested for anti-proliferative activity. Compounds 17e-h demonstrated more effective inhibitory activity than acetazolamide (IC₅₀ 63 nM CA IX and IC₅₀ 92 nM CA XII), with IC₅₀ range of 25-52 nM against CA IX and IC₅₀ range of 31-80 nM against CA XII. To verify selectivity against CA IX and CA XII, carbonic anhydrase inhibitory activity of compounds 17e-h against the physiological CA I and CA II isoforms was carried out. The results showed that compounds 17e-h induced lower inhibitory activity against CA I and CA II with IC₅₀ range of 0.428-0.638 μM (CA I) and 0.095-0.164 μM (CA II), in addition to higher selectivity indices (CA I/CA IX S.I. 8.9-19.92, CA I/CA XII S.I. 5.78-16.06) and (CA II/CA IX S.I. 2.83-4.35, CA II/CA XII S.I. 2.05-3.15) when compared to that of acetazolamide, IC₅₀ of 0.199 μM (CA I), 0.133 μM (CA II) (CA I/CA IX S.I. 3.15, CA I/CA XII S.I. 2.16) and (CA II/CA IX S.I. 2.11, CA II/CA XII S.I. 1.44). Concerning anti-proliferative activity of compounds 17e-h, investigations were done on HEPG-2 cell line with IC₅₀ ranges of 3.44-15.03 μM in comparison, 5-FU and doxorubicin showed IC₅₀ values of 11.80 and 9.53 μM, respectively. Furthermore IC₅₀ of MCF-7 and MDA-MB-231 were determined under both normoxic and hypoxic conditions with IC₅₀ values ranging from 3.18-8.26 μM MCF-7 (normoxic), 1.39-6.05 μM MCF-7 (hypoxic), 7.13-26.3 μM MDA-MB-231 (normoxic), 0.76-16.3 μM MDA-MB-231 (hypoxic) using acetazolamide and SLC-0111 as selective CA inhibition references. Moreover, compounds 17e-h demonstrated greater safety against the normal cell line, MCF-10A, with IC₅₀ of 23.06-99.50 μM in comparison to 5-FU and doxorubicin IC₅₀ of 59.8 and 71.8 μM respectively. They also demonstrated (MCF-7 S.I. range of 3.77-31.28) in contrast to doxorubicin (S.I. 13.72) and (HepG-2 S.I. range of 3.60-6.95) in comparison to doxorubicin (S.I. 7.53). In relation to CA IX, XII inhibition, molecular docking of and ADME studies of sulfonamide derivatives 17a-l with CA IX (PDB: 5FL6) and CA XII (PDB: 1JD0) was carried out. Additionally, molecular dynamic simulation was carried out for compounds 17e and 17g which maintained good stability inside the active sites of both enzymes, with average RMSDs of 2.3 Å and 2.1 Å, respectively.