Discovery of A Novel Series of Quinazoline-Thiazole Hybrids as Potential Antiproliferative and Anti-Angiogenic Agents

Considering the pivotal role of angiogenesis in solid tumor progression, we developed a novel series of quinazoline-thiazole hybrids (SA01-SA07) as antiproliferative and anti-angiogenic agents. Four out of the seven compounds displayed superior antiproliferative activity (IC₅₀ =1.83-4.24 µM) on HepG2 cells compared to sorafenib (IC₅₀ = 6.28 µM). The affinity towards the VEGFR2 kinase domain was assessed through in silico prediction by molecular docking, molecular dynamics studies, and MM-PBSA. The series displayed a high degree of similarity to sorafenib regarding the binding pose within the active site of VEGFR2, with a different orientation of the 4-substituted-thiazole moieties in the allosteric pocket. Molecular dynamics and MM-PBSA evaluations identified SA05 as the hybrid forming the most stable complex with VEGFR2 compared to sorafenib. The impact of the compounds on vascular cell proliferation was assessed on EA.hy926 cells. Six compounds (SA01-SA05, SA07) displayed superior anti-proliferative activity (IC₅₀ = 0.79-5.85 µM) compared to sorafenib (IC₅₀ = 6.62 µM). The toxicity was evaluated on BJ cells. Further studies of the anti-angiogenic effect of the most promising compounds, SA04 and SA05, through the assessment of impact on EA.hy296 motility using a wound healing assay and in ovo potential in a CAM assay compared to sorafenib, led to the confirmation of the anti-angiogenic potential.