In the title compound, C16H8N6O2S2·2C2H6OS, the phenanthroline molecule resides on a twofold axis, and the asymmetric unit also contains a slightly disordered [occupancy ratio for S atom of 0.95 (3):0.047 (3)] molecule of dimethyl sulfoxide. The O atoms of the solvent molecule accept hydrogen bonds from the N-H groups of the five-membered 2,3-dihydro-1,3,4-oxadiazole-2-thione ring. This ring is nearly coplanar with the phenanthroline ring, with a dihedral angle between their least-squares planes of 8.86 (6)°. In the crystal, the molecules are linked by C-HO interactions.
M. A. Rahman, M. Karim, M. Arifuzzaman, T. Siddiquee and L. M. Daniels "2,9-Bis(5-sulfanylidene-4,5-dihydro-1,3,4-oxadiazol-2-yl)-1,10-phenanthroline dimethyl sulfoxide disolvate" Acta Cryst. (2014). E70, o321-o322 https://doi.org/10.1107/S1600536814003304