4-Chloro-9-phenyl-7-(2-thienyl)pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidine (5) and 3-amino-3,4-dihydro-4-imino-9-phenyl-7-(2-thienyl)pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidine (19) were prepared and employed as precursors for synthesizing the fused-ring compounds of the title.
