The condensation of several primary amines with 4-cyano-5-dialkoxymethylenaminooxazole gave 6-substituted 5-alkoxy-7 (6H)-immooxazolo [5, 4-d] pyrimidines. These compounds were converted into 3-substituted xanthines by treatment with aqueous alkali or by heating in formamide. The present reaction was compared with an analogous reaction, formation of 9-substituted hypoxantines via 7-aminooxazolo [5, 4-d] pyridimine derivatives, and the ...
