Design, click synthesis, and biological evaluation of novel uracil-1,2,3-triazole hybrids as dual EGFR/CDK1 inhibitors: antiproliferative activity, mechanistic insights, and in silico studies

Abstract

A novel series of uracil–1,2,3-triazole hybrids was designed, synthesized, and evaluated as dual EGFR/CDK1 inhibitors to target cancer cell proliferation and survival. Synthesis was initiated via the nucleophilic substitution of 2-chloro-N-(1,3-dimethyl-2,6-dioxo-pyrimidin-4-yl)acetamide (3) with sodium azide, yielding the key intermediate 4. Subsequent copper-catalyzed azide–alkyne cycloadditions (CuAAC) with various terminal alkynes and 1,3-dicarbonyls afforded the target triazole analogues 6a,b, 8a–c, and 10b,c. In vitro antiproliferative screening against a panel of four human cancer cell lines (MCF-7, HT29, PANC1, A549) and one normal cell line (Vero) identified compound 10a as a potential candidate. Compound 10a exhibited potent dual inhibitory activity, with IC50 values of 0.082 µM and 0.131 µM for EGFR and CDK1, respectively; it was about 2.4-fold less potent than erlotinib against EGFR but about 4.8-fold more potent than roscovitine against CDK1. Mechanistically, 10a induced significant G0/G1-phase cell-cycle arrest (74.89% versus 60.04% in control) and increased apoptotic cells (early plus late apoptosis, 13.55% versus 1.16% in control) in HT29 cells, accompanied by upregulation of Caspase-3 and BAX, with a rise in Bcl-2 whose significance remains to be established. Molecular docking predicted that 10a can occupy the ATP-binding pockets of both EGFR and CDK1, and normal-mode analysis (iMODS) suggested that the docked complexes are structurally plausible. Computational ADMET profiling, however, flags several liabilities for 10a, including predicted hepatotoxicity, low predicted oral absorption and a short predicted half-life. These findings highlight the uracil–triazole scaffold, specifically compound 10a, as a promising starting point for the development of targeted dual EGFR/CDK1 anticancer therapeutics.