Pyrimidine derivatives and related compounds. XXXIII. Reactions of 6-bromomethyl-5-formyl-1,3-dimethyluracil and its hydrazones with nucleophiles. Synthesis of pyrrolo(3,4-d)pyrimidines and pyrimido(4,5-d)pyridazines.
The reactions of 6-bromomethyl-5-formyl-1, 3-dimethyluracil (1) and its hydrazones (6a and 6b) with nucleophiles were investigated. Treatment of 1 with primary amines or hydrazines afforded pyrrolo [3, 4-d] pyrimidines or pyrimido [4, 5-d] pyridazines, respectively. When 6-bromomethyl-1, 3-dimethyluracil-5-carboxaldehyde tosylhydrazone (6a) was treated with hydrazine hydrate, it was readily converted into pyrrolo [3, 4-d] pyrimidine (7) and pyrimido [4, 5-d] pyridazine (8). The reaction of 6-bromomethyl-1, 3-dimethyluracil-5-carboxaldehyde acetylhydrazone (6b) with hydrazine hydrate gave N-aminopyrrolo [3, 4-d] pyrimidine (9).
group is described. Reaction of 5-carbonyl substituted 1,3,6-tri-methyluracils (I) with dimethyl acetylenedicarboxylate or electron-deficient olefines affords quinazoline derivatives (III-VI) via pyrimidine(Z)-dienols (II) formed by base-catalyzed isomerization.