In the title mol-ecule, C(24)H(20)N(2), the pyrazine ring is significantly distorted from planarity, presumably due to steric crowding, and its conformation is well described as a flattened twist-boat. The benzene ring adjacent to the ethyl group forms dihedral angles of 53.79 (13) and 85.47 (12)° with the other benzene rings; the dihedral angle between adjacent benzene rings is 57.90 (12)°. The ethyl group is disordered over two positions; the site-occupancy factor of the major component is 0.546 (4). No hydrogen bonds are found in the crystal structure.