Molecular signature exploration of novel Pyrazolone-derived sulfonamides against colorectal Cancer: Synthesis,...

Colorectal cancer remains a major global health challenge, highlighting the need for effective and selective anticancer agents. In the present study, a series of pyrazolone-derived sulfonamide analogues (Keum and Giovannucci, 2019a, 2019b; Morgan et al., 2023; Lee et al., 2026; Capuozzo et al., 2025; Li et al., 2024; Xie et al., 2020; Gavrić et al., 2025 (1-8)) was designed, synthesized, and evaluated for anti-colorectal cancer activity. Structural characterization of the synthesized compounds was accomplished using ¹H NMR, ¹³C NMR, and HREI-MS analyses. The cytotoxic potential of the compounds was investigated against HCT-116 and HT-29 colorectal cancer cell lines, while HEK-293 cells were used to assess selectivity toward normal cells. Among the synthesized derivatives, analogue 7 exhibited the strongest antiproliferative activity with IC₅₀ values of 1.80 ± 0.20 μM and 2.00 ± 0.20 μM against HCT-116 and HT-29 cells, respectively, and showed reduced toxicity toward HEK-293 cells (IC₅₀ = 34.60 ± 0.20 μM). The selectivity index of 19.22 and 17.30 was calculated for potent compound 7. Molecular docking studies revealed that compound 7 exhibited the strongest binding affinity toward carbonic anhydrase IX (CA IX), with a docking score of -12.49 kcal/mol, forming favorable interactions within the enzyme active site. Enzyme kinetic analysis and Lineweaver-Burk plots suggested a competitive inhibition mechanism for the lead compound. Additionally, DFT and ADMET investigations confirmed favorable electronic characteristics, molecular stability, drug-likeness, and low predicted toxicity. These findings suggest that pyrazolone-derived sulfonamides represent promising scaffolds for future colorectal cancer drug development.