Ethyl 6-methyl-3-(2-methyl-prop-1-en-yl)-2-oxo-4-phenyl-1,2,3,4-tetra-hydro-pyrimidine-5-carboxyl-ate.

In the mol-ecule of the title compound, C(18)H(22)N(2)O(3), the dihydro-pyrimidinone ring adopts an envelope conformation. The dihedral angle between the phenyl ring and the mean plane through the enamine fragment is 86.04†(7)°. The mol-ecular conformation is stabilized by an intra-molecular C-H⋯O hydrogen bond. In the crystal, inter-molecular N-H⋯O hydrogen bonds link pairs of mol-ecules into centrosymmetric dimers.