Synthesis and in vitro study of pyrimidine-phthalimide hybrids as VEGFR2 inhibitors with antiproliferative activity.

Aim: Thalidomide, a once notorious sedative, is now clinically used as an antitumor agent. We aimed to use it as a lead compound for designing pyrimidine-phthalimide hybrids. Materials & methods: Nucleophilic substitution reaction of thalidomide analog 4 with primary and/or secondary aliphatic amines afforded pyrimidine-phthalimide hybrids 5a-g , 6 and 7a-d . Results & conclusion: Compound 7c showed high antiproliferative activity against four cell lines: HepG-2 (IC 50 : 7.86 ± 0.5 μM), MCF-7 (IC 50 : 2.77 ± 0.1 μM), HCT-116 (IC 50 : 5.73 ± 0.4 μM) and PC-3 (IC 50 : 8.32 ± 0.5 μM), with selective cytotoxicity for WI-38 (IC 50 : 43.2 ± 2.56 μM). 7c arrested MCF-7 cells at S phase of the cell cycle and increased the total apoptotic cells by 50-fold. 7c inhibited VEGFR2 in vitro (IC 50 : 0.130 ± 0.02 μM). 7c was capable of binding at the VEGFR2 binding site, forming hydrogen bond interactions with Asp1046 and Glu885 in a similar way to sorafenib.