Synthesis of thiourea derivatives from m-methoxycinnamic acid as antiangiogenic candidate

Microwave-assisted nucleophilic acyl substitution was employed to obtain thiourea derivatives (3a, 3b, 3c) from m-methoxycinnamic acid (1). This synthesis method successfully yielded 60-70% reaction product. In vivo anti-angiogenic evaluation was conducted by chick chorioallantoic membrane model, by which each of the derivative at dose 30, 60, and 90 μg induced by bFGF and compared to celecoxib 60 μg as positive control. It was found that all of the synthesized compound at the tested dose were able to inhibit neovascularization and formation of endothelial cell of new blood vessels by 51-75%. In silico analysis predicted that the anti-angiogenesis mechanism of all the synthesized compounds is through the inhibition of EGFR kinase and COX-2. N atom acts as hydrogen bonding acceptor by residue Gly526 of COX-2. While thiourea moieties of 3a-c have hydrophobic interaction by residues Ser530, Tyr385, and Leu352. In addition, the carbonyl group of thiourea of compound 3a-c inhibit EGFR kinase through the interaction with lys745. The pKCSM data revealed that 3a-c absorbed in intestine by 89-92%, and acut toxicity in rat category 4, suggesting that the compounds show good absorption, and low toxicity. In conclusion, this study successfully synthesized thiourea derivatives, which have anti-angiogenesis activity, tested by CAM model.