9-Benzyl-7-[(E)-2-butenyl]-2,3-dihydro-6-hydroxy-1,3-dimethylpyrimido[2,1-f]purine-4,8(1H,9H)-dione

The two independent molecules of C₂₁H₂₃N₅O₃ in the asymmetric unit of the title compound possess similar conformations. In each molecule, an almost planar purine ring is fused to a reduced pyrimidine ring. The dihedral angles between the fused-ring plane and phenyl-ring plane of the molecules are different [115.5 (2)° for molecule (1) and 68.0 (1)° for molecule (2)]. The O14...O13 distances of 2.478 (5) Å for molecule (1) and 2.467 (5) Å for molecule (2) indicate the presence of intramolecular hydrogen bonding.

-1