Design, green synthesis, and anticancer evaluation of novel sulfaguanidine-based heterocycles as multi-target inhibitors of the VEGFR-2/PI3K/AKT/mTOR pathway.

The pursuit of multi-target anticancer agents is a strategic approach to overcome drug resistance and improve selectivity. This study focuses on the design of novel heterocyclic compounds incorporating a sulfaguanidine moiety, targeting key pathways in cancer progression. A novel diazonium intermediate was synthesized from sulfaguanidine and used to prepare a series of pyrimidine and triazine derivatives 3-8 via both conventional and eco-friendly microwave techniques. All compounds were characterized by spectroscopic methods. The cytotoxic activity was evaluated against five human cancer cell lines (HEPG2, MCF7, A431, A375, and A549) and normal HSF fibroblasts. The mechanism of the lead compounds 3 and 4 was investigated through cell cycle analysis, qPCR analysis of VEGFR-2, PI3K, AKT, mTOR, Caspase-3, and CDC42 genes, and comprehensive molecular docking studies against the corresponding protein targets. ADMET profiles were also predicted. Microwave synthesis significantly improved reaction efficiency. Compounds 3 and 4 exhibited the most potent and selective cytotoxicity, with compound 4 showing activity against A431 cells (IC₅₀ = 4.87 µM). Mechanistic studies revealed compound 3 induced G2/M arrest, while Compound-4 caused G1 arrest. QPCR analysis confirmed significant downregulation of VEGFR-2, PI3K, AKT, mTOR, and CDC42, alongside upregulation of pro-apoptotic Caspase-3. Docking studies supported strong binding affinities to VEGFR-2, PI3K, AKT, and mTOR, correlating with the biological data. The integrated chemical and biological approach identified compounds 3 and 4 as promising multi-target agents. Their ability to disrupt angiogenesis, survival signaling, and cell cycle progression, while inducing apoptosis, highlights their potential as lead compounds for further anticancer development.