Ethyl 2-methyl-6-(propan-2-yl-amino)-4-sulfanyl-idene-3H,11H-pyrimido[1,6-c]quinazoline-1-carboxyl-ate

The title compound, C(18)H(22)N(4)O(2)S, contains a substituted pyrimidine ring fused to both a benzene ring and a substituted thioxopyrimidine ring. The pyrimidine and thioxopyrimidine rings adopt distorted chair conformations. In the crystal, adjacent mol-ecules are linked by pairs of N-H⋯S and N-H⋯O hydrogen bonds to generate centrosymmetric R(2) (2)(8) and R(2) (2)(16) loops, respectively. This combination leads to [100] chains of mol-ecules.