Organotin-Catalyzed Synthesis, Characterization, Anticancer and Antioxidant Activities, and Molecular Modeling Studies of Nimesulide Ureas as Potential MetAP (Type II) Inhibitors

Abstract

In this study, a new series of nimesulide-derived ureas (3a–j) was designed and synthesized to investigate structural modifications of nimesulide and to evaluate their biological activity. The compounds were obtained in high yields (68–88%) under organotin-catalyzed conditions, and their structures were unequivocally established using comprehensive spectroscopic techniques, including 1H NMR, 13C NMR, FTIR, and HRMS. Following structural confirmation, the antioxidant properties of the synthesized derivatives were evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, where compounds 3e, 3f, and 3i displayed notable radical-quenching activity. The nimesulide derivative 3i exhibited notable cytotoxicity across multiple breast cancer models, including the triple-negative MDA-MB-231 and 4T1 cell lines, as well as the luminal MCF-7 subtype. Consistent with its enhanced potency, 3i triggered a robust shift from cell viability to programmed cell death, characterized predominantly by a dramatic accumulation of late-apoptotic populations following 72 h of treatment. This apoptotic signature was especially pronounced in Triple-Negative Breast Cancer (TNBC) cells, in which viable cell fractions were nearly eliminated. These findings suggest that structural modification of the nimesulide derivative can substantially improve its in vitro anticancer efficacy. Taken together, the observed cytotoxic and apoptosis-inducing effects suggest that compound 3i may represent a potential NSAID-based anticancer candidate. In line with its pronounced cytotoxic and pro-apoptotic profile, compound 3i also demonstrated strong inhibition of the MetAP2 enzyme, further reinforcing its potential as a multifunctional nimesulide-based anticancer agent. To obtain insight into the binding pose and binding energy of all synthesized compounds (3a−j) were docked into the active site of the MetAP2 enzyme. The computational inhibition constant values were correlated with the experimental values. To test the dynamic behavior of MetAP2-inhibitor complexes, a molecular dynamics (MD) simulation was also carried out for a 200 ns duration. MD revealed that the drugs bind to the active site of the MetAP2 enzyme, as indicated by stable RMSD and RMSF plots. In conclusion, in silico results and in vitro studies suggest that the nimesulide derivatives may be novel, potential NSAID-based anticancer drug candidates for treating breast, prostate, gastric, and glioblastoma.