Synthesis, crystal structure and Hirshfeld surface of ethyl 2-[2-(methyl-sulfan-yl)-5-oxo-4,4-diphenyl-4,5-di-hydro-1 H -imidazol-1-yl]acetate (thio-phenytoin derivative).

The di-hydro-imidazole ring in the title mol-ecule, C 20 H 20 N 2 O 3 S, is slightly distorted and the lone pair on the tri-coordinate nitro-gen atom is involved in intra-ring π bonding. The methyl-sulfanyl substituent lies nearly in the plane of the five-membered ring while the ester substituent is rotated well out of that plane. In the crystal, C-H⋯O hydrogen bonds form inversion dimers, which are connected along the a - and c- axis directions by additional C-H⋯O hydrogen bonds, forming layers parallel to the ac plane. The major contributors to the Hirshfeld surface are C⋯H/H⋯C, O⋯H/H⋯O and S⋯H/H⋯S contacts at 20.5%, 14.7% and 4.9%, respectively.