Synthesis of some new Thienopyrimidine with Benzoxazine, Quinazoline and Azole Moieties

Reaction of thienopyrimidinoyl chloride 3 with 2-aminocy-clohexanothiophene-3-carboxamide 4 yielded thienopyrimidine derivative 5 that undergoes cyclodehydration to afford thienopyrimidine 6. The synthesis of benzamidazole 8 and benzoxazole 10 derivatives was achieved by condensation of thienopyrimidinoyl chloride 3 and o-phenylenediamine / o-aminophenol followed by cyclization. Reaction of 4-thio-6-methyl-2-(p-methoxyphenyl)-5-acetylpyrimidine 1 and N(o-carboxyphenyl) chloro-acetamide 11 yielded pyrimidine derivative 12 that cyclized to benzoxazine 13. Compound 13 was transformed to quinazoline derivatives 14a-c and 16. Reaction of 13 with semicarbazide yielded triazoloquinazoline 18.