Development of

Nitrosation and cyclization of 4-(3-aminothieno[2,3-b]pyridine-2-yl)-2H-chromen-2-ones 1 afforded substituted 6H-chromeno[3,4-c]pyrido[3',2':4,5]thieno[2,3-e]pyridazin-6-ones 2 that inhibited the intermediary filament protein, vimentin, at low micromolar concentrations. This inhibition promoted the secretion of Prostate Apoptosis Response-4 protein (Par-4), which selectively triggered apoptosis in prostate cancer cells such as CWR22Rv1, LNCaP-derivative C4-2B, PC-3 and its aggressive analog, PC-3 MM2.