Heterocyclic-Derivatives of Guanidine. VI. Formation and X-Ray Structure Determination of 2-Dimethylamino-7,8-diphenyl-4,6-dihydropyrrolo[1,2-a]pyrimidine-4,6-dione

Abstract

The structure N-(2-dimethylamino-4-oxo-7,8-diphenyl-4,6-dihydropyrrolo [l,2-a]pyrimidi n-6-yl-idene)acetamide (3) is proposed for a compound derived from the action of ketene on 2-(2-imino- 3,4-diphenyl-2H-pyrrol-5-yl)-1,1,3-trimethylguanidine (1; R¹ = R² = R³ = Me) on the basis of the crystal structure of its hydrolysis product, the oxo-compound 2-dimethylamino-7,8-diphenyl-4,6-dihydropyrrolo[l,2-a]pyrimidine-4,6-dione (4), the structure of which was determined by X-ray analysis. A lower homologue of (3), N-(2-methylamino-4-oxo-7,8-diphenyl-4,6-dihydro- pyrrolo[l,2-a]pyrimidin-6-ylidene)acetamide (2), and some related compounds are described.