An efficient method is applied for the synthesis of novel 2-(2-chloroquinolin-3-yl)-N-alkylimidazo[1,2-a]pyridin-3-amine derivatives. The method is based on a two-step approach from acetanilide, 2-chloro-3-formyl quinoline, 2-aminopyridine, and isocyanide under mild reaction conditions. In the first step, acetanilide forms 2-chloroquinoline-3-carbaldehyde in the presence of phosphoryl chloride. The synthesized 2-chloroquinoline-3-carbaldehyde takes part in a multicomponent reaction with 2-aminopyridine, and isocyanide in the presence of trimethylsilyl chloride. The reaction is facile and the products are synthesized in high isolated yields under mild reaction conditions. K E Y W O R D S 2-(2-chloroquinolin-3-yl)imidazo[1,2-a]pyridin-3-amine, multicomponent reaction, trimethylsilyl chloride

Background Cancer is the most cause of morbidity and mortality, and a major public health problem worldwide. In this context, two series of quinazolinone 5a–e and dihydroquinazolinone 10a–f compounds were designed, synthesized as cytotoxic agents. Methodology All derivatives (5a–e and 10a–f) were synthesized via straightforward pathways and elucidated by FTIR, 1H-NMR, CHNS elemental analysis, as well as the melting point. All the compounds were evaluated for their in vitro cytotoxicity effects using the MTT assay against two human cancer cell lines (MCF-7 and HCT-116) using doxorubicin as the standard drug. The test derivatives were additionally docked into the PARP10 active site using Gold software. Results and discussion Most of the synthesized compounds, especially 5a and 10f were found to be highly potent against both cell lines. Synthesized compounds demonstrated IC50 in the range of 4.87–205.9 μM against HCT-116 cell line and 14.70–98.45 μM against MCF-7 cell line compared with doxorubicin with IC50 values of 1.20 and 1.08 μM after 72 h, respectively, indicated the plausible activities of the synthesized compounds. Conclusion The compounds quinazolinone 5a–e and dihydroquinazolinone 10a–f showed potential activity against cancer cell lines which can lead to rational drug designing of the cytotoxic agents.