Capan_2026_Med.Chem.Res__

A series of 30 novel azole-sulfonamide urea and thiourea conjugates was rationally designed and synthesized as potential multitarget inhibitors of acetylcholinesterase (AChE) and the human carbonic anhydrase isoforms hCA I and hCA II. The molecular design combined azole-based heterocyclic scaffolds with the classical sulfonamide zinc-binding pharmacophore through urea or thiourea linkers. The synthesized compounds were characterized by FT-IR, (1)H NMR, (13)C NMR, and high-resolution mass spectrometry and subsequently evaluated in vitro against the three target enzymes. Several derivatives exhibited potent nanomolar inhibitory activity. Compounds 11, 6, 26, and 16 were the most active AChE inhibitors, with IC50 values of 23.89, 30.13, 34.65, and 36.47 nM, respectively. Compounds 25, 26, 29, and 20 displayed the strongest inhibition of hCA I, with IC50 values ranging from 40.76 to 46.82 nM, whereas compounds 11 and 17 were the most active against hCA II, both exhibiting an IC50 value of 57.75 nM. Selectivity analysis based on the IC50(hCA I)/IC50(hCA II) ratio indicated limited isoform discrimination overall, with selectivity indices ranging from 0.42 to 1.26. Most derivatives showed a modest relative preference toward hCA I, whereas compounds 13, 17, 18, and 21 displayed modest preference toward hCA II, with compound 17 showing the highest hCA II selectivity index (SI = 1.26). Notably, compounds 11 and 26 showed a well-balanced multitarget profile across all three tested enzymes. Molecular docking and MM-GBSA calculations suggested plausible binding modes involving hydrogen bonding, aromatic interactions, hydrophobic contacts, and, for selected carbonic anhydrase complexes, sulfonamide-mediated coordination with the catalytic Zn^2 ion. Overall, the experimental and computational findings identify azole-sulfonamide urea/thiourea conjugates as promising scaffolds for the further development of multitarget enzyme inhibitors and provide preliminary structure-activity insights for subsequent optimization.