Studies On The Synthesis Of 2-pyridone Derivatives

In recent years, Pyridone derivatives have become one of hot spots in chemistry researchareas, due to its significant biological activity. Pharmacological research show that: a lot ofcompounds have a potential effect of anti-tumor. There are two main synthetic methodsreported in the literature: one is cycloaddition, the other is cyclocondensation.α-oxo ketene dithioacetals are a kind of versatile intermediates in organic synthesis. Itcan be widely used in forming aromatic and heterocyclic compounds. In recent years, ourresearch group has devoted to the synthetic applications ofα-oxo ketene dithioacetals.Based on the research ofα-oxo ketene dithioacetals, in this theme, we describe a new, easyand straightforward synthesis of multi-substituted pyridone derivatives.Substratesα-oxo ketene dithioacetals were treated with aromatic aldehyde andα-alkenoyl ketene-(S,S)-acetals were obtained in good yields. From the view of structure,α-alkenoyl ketene-(S,S)-acetals contain two enone fragments, so they should have the potentialto be attacked two times by binucleophilic species,α-alkenoyl ketene-(S,S)-acetals anddiethyl malonate were carried out with K₂CO₃ in DMF, -SC2H5 was substituted with -CH(COOC₂H5)₂. Finally, multi-substituted pyridone derivatives were obtained viaintramolecular caprolactam proceed.In this theme, 9 new products were synthesized and characterized via MS, ¹HNMR,¹³CNMR.