Synthesis, Labeling and Biological Evolution of New Thiopyrano[2,3-b]Pyridine Derivatives as Potential Anticancer Agents.

The new thiopyrano[2,3-b]pyridines 4-9 could be synthesized from the nicotinonitrile derivative 1. The cytotoxicity activity of the selected compounds 5, 6 and 8 was tested against MCF-7 and HCT-116 cell lines. The compound 5 (TP5) exhibited significant inhibitory activity and displayed the most potent activity, more than 6 and 8.