organic compounds
The title compounds, C32H28N2O4, (I), and C32H28N2S4, (II), respectively, are tetrasubstituted pyrazines and both possess Ci symmetry. They differ only in the hetero atom (X) of the –CH2XPh side-arm substituents: X = O in (I) and S in (II). Compound (I) has an overall S-shape with a pair of adjacent –CH2OPh side arms alternately above and below the plane of the central pyrazine ring. The phenyl rings are inclined to one another by 12.63 (18)° and there is one intramolecular C—HO hydrogen bond involving adjacent –CH2OPh side arms. In compound (II), adjacent –CH2SPh side arms point in opposite directions with respect to the pyrazine ring plane, with the phenyl rings inclined at 60.45 (8)°. Both structures have weak C—Hπ intermolecular interactions.