A Convenient Synthesis and Biological Activity of Novel Pyrido[4,3-d] pyrimidin-4(3H)-ones

摘要

Fifteen novel 2-alkylamino-3-aryl-8-cyano-5-methyl-7-(methylthio)-pyrido[4,3-d]pyrimidin-4(3H)-ones 6a-6o were designed and have been successfully synthesized via tandem aza-Wittig and annulation reactions with the corresponding iminophosphorances 4, aryl isocyanate, and amines in good yields. Their structures were clearly verified by IR, ~1H NMR, EI-MS spectroscopy and elemental analysis, and in the case of compound 6i, analyzed by single-crystal X-ray diffraction further. The preliminary results of an in vivo bioassay showed that some compounds display moderate antifungal activity.