2,3-Bis(furan-2-yl)pyrazino-[2,3-f][1,10]phenanthroline.

The mol-ecule of the title compound, C22H12N4O2, is located on a twofold rotation axis. The dihedral angle between the furan and pyrazine rings is 34.8 (7)°, and that between the furan rings is 46.92 (7)°. A π-π stacking interaction occurs between adjacent pyrazino[2,3-f][1,10]phenanthroline units, with an interplanar distance of 3.5862 (12) Å.

2,3-Bis(thio-phen-2-yl)pyrazine-[2,3-f][1,10]phenanthroline.

The mol-ecule of the title compound, C(22)H(12)N(4)S(2), shows no crystallographic symmetry. The thiophene rings form different dihedral angles [40.15 (9) and 15.43 (10)°] with the pyrazine ring. A strong π-π stacking inter-action occurs between adjacent pyrazine-[2,3-f][1,10]phenanthroline units with an inter-planar distance of 3.4352 (16) Å.