Pyrrolo[2,3-d]pyrimidine derivatives in the synthesis of a novel heterocyclic system 2a,5a,7-triazaacenaphthylene

A convenient method for the synthesis of methyl 8-oxo-3H,8H-2a,5a,7-triazaacenaphthylene-2-carboxylate by iodination of 7-allyl-4-methoxypyrrolo[2,3-d]pyrimidine-6-carboxylic acid methyl ester followed by elimination of hydrogen iodide has been developed. The use of 4-methoxypyrrolo[2,3-d]pyrimidine-6-carboxylic acid as the starting compound led to the formation of iodomethylpyrimido[5',4':4,5]-pyrrolo[2,1-c][1,4]oxazine, a promising precursor for the synthesis of a new tricyclic system based on pyrrolo[2,3-d]pyrimidine.