Synthesis and antitumor evaluation of some new thiazolopyridine, nicotinonitrile, pyrazolopyridine, and polyhydroquinoline derivatives using ceric ammonium nitrate as a green catalyst

Abstract

AbstractA novel series of thiazolo[5,4‐b]pyridine, polysubstituted pyridines, pyrazolo [3,4‐b] pyridine‐5‐carbonitriles, and polyhydroquinoline were synthesized via one‐pot reaction of 2‐iminothiazolidin‐5‐one, acetyl pyridine, pyrazolone, and/or cyclohexanone with various aldehydes, some active methylene and ammonium acetate in the presence of ceric ammonium nitrate (CAN). The resulting compounds were generated in high yields in a short amount of time, and the structures of the novel compounds were confirmed using IR, 1H NMR, 13C‐NMR, and mass spectra. The cytotoxic activity of 15 substances was tested in vitro against HePG‐2 and Caco‐2 cell lines. The results of antitumor assay confirmed that quinoline 12d compounds possess higher cytotoxic activity against two cell lines closed to doxorubicin, which is used as a standard anticancer drug. Also, 12c compounds are more efficient antitumor against the 2‐cell lines. While compounds 1 showed moderate activity toward Caco‐2. On the other hand, most of the tested compounds exhibited moderate to low cytotoxic activity toward the two cell lines. Based on the results, some of the newly synthesized derivatives showed excellent antitumor activity that qualified them for biomedical applications.