SYNTHESIS WITH NITRILES .92. SYNTHESIS OF 5-FORMYLCYTOSINE DERIVATIVES

The reactivity of 3-dimethylamino-2-formylpropenenitrile (1) with vari ous amino compounds is studied. Thus, condensation of 1 with anilines gives the corresponding azomethines (2a-c). Reaction of 1 with thioure a and guanidne resp., leads to 5-formylthiocytosine (3) and 2-amino-5- cyanopyrimidine (4). The 2-formyl-3-ureidopropenenitriles (5a-i) can b e obtained by reaction of 1 with urea and substituted ureas. 5a-i can easily be cyclized to 3-substituted 5-formylcytosines (6-e). Condensat ion of 6 with aniline, benzylamine and phenylhydrazine leads to the az omethines (7a-i). Pyrido [ 2,3-d ] pyrimidine-6-carbonitriles (8a, 8b, Sd and 83) are obtained by reaction of 6 with malononitrile.