Lactam and acid amide acetals 68. 1-Cyanomethyl-2-pyrrolidone diethylacetal in the synthesis of 7,8-trimethylenepurine derivatives

1-Cyanomethyl-2-cyaniminopyrrolidine was synthesized by the reaction of 1-cyanomethyl-2-pyrrolidone diethylacetal with cyanamide. The product undergoes Thorpe—Ziegler cyclization under the influence of sodium ethoxide to give 2-amino-3-cyano-5,6-dihydro-7H-pyrrolo1,2-a]imidazole, from which 4-amino derivatives of pyrrolo2,1-f]purine were synthesized.See 1] for Communication 67.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 754–758, June, 1991.