Abstract
In the title compound, C17H16N2O2S, the pyrazinone ring is non-planar (r.m.s. deviation = 0.1595 A), with maximum deviations for the 4-position N atom and the adjacent non-fused-ring C atom of 0.2557 (15) and -0.2118 (16) A, respectively. The dihedral angle between the benzyl ring and pyrazinone rings is 30.45 (18)degrees. Intermolecular N-H...O hydrogen-bonding interactions forms inversion dimers which lead to eight-membered R (2) 2(8) ring motifs. The dimers are further connected by C-H...O interactions.