Reaction of 2-hetarylacetonitriles with ethyl 2-alkylsulfanyl-4-chloro-5-pyrimidinecarboxylates. Synthesis of new condensed pyrimidines

Reactions of 2-hetarylacetonitriles 1 with ethyl 2-alkylsulfanyl-4-chloro-5-pyrimidinecarboxylates 4 were studied. The interaction of pyridine, benzimidazole and benzothiazole, derivatives 1a-d affords a series of new condensed pyridopyrimidines 5-7. In the case of benzoxazole- and 4-arylthiazole derivatives le-h ethyl 4-[(2-hetaryl)-cyano-methyl]-2-alkylsulfanylpyrimidine-5-carboxylates 9a-f were formed. Reactions of quinazoline derivatives 1i,k afford stable intermediates 9h,i which formed the cyclic compound 12 of angular structure in the presence of potash. The influence of the basicity of heterocycles and of steric factors on the intramolecular acylation reaction was studied. (C) 2002 Elsevier Science Ltd. All rights reserved.