3‐Benzyl‐2‐butyl­amino‐5,6,7,8‐tetra­hydro­benzothieno[2,3‐d]pyrimidin‐4(3H)‐one

In the title molecule, C21H25N3OS, the fused thio­phene and pyrimidine rings are essentially coplanar. In the crystal structure, N—H⋯O and weak C—H⋯O hydrogen bonds link the mol­ecules, forming one-dimensional chains along [010].