Synthesis and cytotoxic evaluation of novel quinozalinone derivatives with substituted benzimidazole in position 3

Quinazolinone and benzimidazole are both fused heterocyclic compounds which have shown valuable biological properties including cytotoxic, antibacterial, and antifungal activities. In this study, a series of novel quinazolinone derivatives substituted with benzimidazole were synthesized in two parts. In the first part 2 - phenyl - 1H - benzimidazol - 6 - amine (4) was synthesized from the reaction of 4-nitro-o-phenylenediamine and benzoic acid. In the second part, new 3-(2-phenyl-1H benzoimidazol-5-yl)- 3H-quinazolin-4-one derivatives (8a-8f) were also prepared. Finally compound 4 was reacted with the different benzoxazinone derivatives (8a-8f) to give the target compounds. The structures of the synthesized compounds were confirmed by IR and 1HNMR. Cytotoxic activities of the final compounds were assessed at 100, 200, 300, 400, and 500 μM against MCF-7 and HeLa cell lines using the MTT colorimetric assay. Almost all compounds exhibited good cytotoxic activity against both cell lines. Compound 9d demonstrated the highest cytotoxic activity against MCF7 and Hela cell lines with IC50 70 μM and 50 μM, respectively.