Synthesis, biological evaluation and molecular docking studies of novel amino acid-conjugated pyrazole-benzenesulfonamide hybrids against carbonic anhydrase I/II and acetylcholinesterase enzymes

A series of novel amino acid-conjugated pyrazole-benzenesulfonamide derivatives ( G1 - 7 ) was synthesized and evaluated against carbonic anhydrase I/II and acetylcholinesterase enzymes. Among the compounds, ethyl (1-(4-sulfamoylphenyl)-5-(thiophen-2-yl)-1 H -pyrazole-3-carbonyl)tryptophanate ( G3 ) emerged as the most potent hCA I ( K i : 28.63 ± 0.57 nM) and hCA II ( K i : 48.80 ± 13.00 nM). Methyl (1-(4-sulfamoylphenyl)-5-(thiophen-2-yl)-1 H -pyrazole-3-carbonyl)tryptophanate ( G5 ) demonstrated the highest inhibitory activity against AChE with K i : 61.34 ± 8.88 nM. Molecular docking studies were also conducted, and binding scores were calculated for compounds G3 -7.784 kcal/mol (hCA I), -7.461 kcal/mol (hCA II), and G5 -9.102 kcal/mol (AChE). Experimental findings demonstrated that G3 , an ethyl ester tryptophan derivative, is highly effective in inhibiting hCA I/II, while the methyl ester derivative G5 shows superior efficacy against AChE. Additionally, the phenylalanine-based hybrid G4 was found to be a more potent inhibitor of hCA II than hCA I. ADMET evaluations revealed that some hybrids possess favorable drug-like characteristics. These findings show that the potential of these compounds as promising structures for subsequent structural optimization and biological investigation.