A series of new 2-(amino/aroxy)-5,8,9-trimethylthieno[3′,2′ : 5,6]pyrido[4,3-d]pyrimidin-4(3H)-one derivatives have been designed and synthesized via an aza-Wittig reaction and structually confirmed by elemental analysis, IR, 1H NMR, EI-MS spectra, and compound II-1 by X-ray diffraction analysis. Their biological activities were also researched and many of them showed good fung...