Discovery of biphenyl-based VEGFR-2 inhibitors. Part 3: Design, synthesis and 3D-QSAR studies

VEGFR-2 plays an essential role in angiogenesis and is a central target for anticancer drug discovery. In order to develop novel VEGFR-2 inhibitors, we designed and synthesized 33 biphenyl amides based on our previously reported lead compound. The biological results indicated that four compounds (18b, 20e, 20h and 20j) are potent VEGFR-2 inhibitors which are comparable to positive control. Compound 18b displayed the most potent VEGFR-2 inhibition with IC₅₀ value of 2.02 nM. Moreover, it exhibited promising antiproliferative activity against MCF-7 and SMMC-7721 cells with IC₅₀ values of 1.47 μM and 5.98 μM, respectively. Molecular docking and 3D-QSAR studies were also carried out. The results indicated that these biphenyl amides could serve as promising leads for further optimization as novel VEGFR-2 inhibitors.