The title compound, C19H18N4OS, crystallizes in space group P1 with Z' = 2. The two molecules in the selected asymmetric unit are nearly enantiomorphous. The molecules are linked by two N-H...N hydrogen bonds [H...N both 2.20 A, N...N = 3.064 (3) and 3.077 (3) A, and N-H...N = 165 and 172 degrees] into C(2)2(10) chains, and these chains are linked into sheets by two independent C-H...pi(arene) hydrogen bonds.