Synthesis and biological evaluation of novel pyridone derivatives containing 1,3,4-thiadiazol as potential anticancer agents.

A series of novel 5,6-disubstituted pyridone derivatives containing 1,3,4-thiadiazol (3a-3p) were synthesized starting from 2,3-dihydroxypyridine via oxidation-Michael additions, condensations and cyclizations. The anticancer activity of the newly synthesized compounds were evaluated against Gastric cancer (MGC-803), hepatocellular cancer (HepG2) and Pulmonary cancer (PC-9) cell lines using the MTT assay. Most compounds exhibited antiproliferative activity against various cancer cells in vitro. Compared with the standard drug 5-fluorouracil, compounds 3a, 3 g and 3 h showed better activity against MGC-803, HepG2 and PC-9 cell lines, respectively. Compound 3 h demonstrated the most potent antitumor activity with IC50 values of 2.43 μM, 1.73 μM and 4.03 μM against MGC-803, HepG2 and PC-9 cell lines, respectively, which was 1.7-4.5 folds more potent than 5-Fluorouracil (IC50 = 10.92 μM 7.15 μM and 6.88 μM against MGC-803, HepG2 and PC-9 cell lines respectively). These findings suggest that compound 3 h shows promise as a lead compound for the development of novel small-molecule anticancer agents.