Reactions of 6‐Acetyl‐4‐methyl‐5‐(1‐pyrrolyl)‐2‐phenylthieno‐ [2,3‐ d ]pyrimidine in Heterocyclic Synthesis: Convenient Route to Some Schiff's Bases, Chalcones, Pyridines, Pyridin‐2(1H)‐ones and 2H‐Pyran‐2‐one Derivatives Incorporating a 5‐(1‐Pyrrolyl)‐2‐phenylthieno[2,3‐ d ]pyrimidine Moiety

Treatment of 6‐acetyl‐5‐amino‐4‐methyl‐2‐phenylthieno[2,3‐ d ]pyrimidine 3 with 2,5‐dimethoxytetra‐hydrofuran afforded the 6‐acetyl‐5‐(1‐pyrrolyl)‐4‐methyl‐2‐phenylthieno[2,3‐ d ]pyrimidine 4 , which can react with appropriate primary amines 5a‐f to yield the corresponding Schiffs base derivatives 6a‐f . The reaction of acetyl compound 4 with appropriate arylaldehydes 14a‐k and arylmethylidenemalononitriles 18a‐f afforded the corresponding 6‐(3‐substituted‐acryloyl)‐5‐(1‐pyrrolyl)‐4‐methyl‐2‐phenylthieno[2,3‐ d ]pyrimidines 15a‐k and 6‐[3‐cyano‐2‐ethoxy‐4‐(4‐substituted‐phenyl)‐pyridin‐6‐yl]‐5‐(1‐pyrrolyl)‐4‐methyl‐2‐phenyl‐thieno[2,3‐ d ]pyrimidines 21a‐f under basic conditions, respectively. On the other hand, the 6‐(3‐cyano‐1,2‐dihydro‐4‐substituted‐2‐oxopyridin‐6‐yl)‐5‐(1‐pyrrolyl)‐4‐methyl‐2‐phenylthieno[2,3‐ d ]pyrimidines 26a,b and 6‐(3‐substituted‐amido‐4‐substituted‐pyran‐2‐on‐6‐yl)‐5‐(1‐pyrrolyl)‐4‐methyl‐2‐phenyl‐thieno[2,3‐ d ]pyrimidines 30a‐c were obtained by intramolecular cyclization of 6‐(3‐dimethylamino‐3‐substituted‐acryloyl)‐5‐(1‐pyrrolyl)‐4‐methyl‐2‐phenylthieno[2,3‐ d ]pyrimidines 23a,b with cyanoacet‐amide 24 and N‐acylglycines 27a,b , respectively.