Crystal structure of 3-{[4-(2-methoxyphenyl)piperazin-1-yl] methyl}-5-(thiophen-2-yl)-1,3,4-oxadiazole-2(3H)-thione

The title compound, C18H20N4O2S2, is a new 1,3,4-oxadiazole and a key pharmacophore of several biologically active agents. It is composed of a methyl(thiophen-2-yl)-1,3,4-oxadiazole-2(3H)-thione moiety linked to a 2-methoxyphenyl unit via a piperazine ring that has a chair conformation. The thiophene ring mean plane lies almost in the plane of the oxadiazole ring, with a dihedral angle of 4.35 (9)degrees. The 2-methoxyphenyl ring is almost normal to the oxadiazole ring, with a dihedral angle of 84.17 (10)degrees. In the crystal, molecules are linked by weak C-H center dot center dot center dot S hydrogen bonds and C-H center dot center dot center dot pi interactions, forming layers parallel to the bc plane. The layers are linked via weak C-H center dot center dot center dot O hydrogen bonds and slipped parallel pi-pi interactions [intercentroid distance = 3.6729 (10) angstrom], forming a three-dimensional structure. The thiophene ring has an approximate 180 degrees rotational disorder about the bridging C-C bond.