organic compounds
There are no direction-specific interactions between the molecules of 3-(2-methoxybenzyl)-2-(2-methoxyphenyl)-1,3-thiazolidin-4-one, C18H19NO3S, (I); the molecules of 3-(4-nitrobenzyl)-2-(4-nitrophenyl)-1,3-thiazolidin-4-one, C16H13N3O5S, (II), are linked by four independent C—HO hydrogen bonds into complex chains of fused rings. In 3-(4-methoxybenzyl)-2-(4-methoxyphenyl)-1,3-thiazolidin-4-one, (III), isomeric with (I), the molecules are linked into sheets by a combination of C—HO and C—Hπ(arene) hydrogen bonds, while in 3-(2-nitrobenzyl)-2-(2-nitrophenyl)-1,3-thiazolidin-4-one, (IV), isomeric with (II), the sheets are built from three independent C—HO hydrogen bonds and one C—Hπ(arene) hydrogen bond, and reinforced by an aromatic π–π stacking interaction. In 3-(2-fluorobenzyl)-2-(2-fluorophenyl)-1,3-thiazolidin-4-one, C16H13F2NOS, (V), where the 2-aryl ring exhibits orientational disorder, the molecules are linked into sheets by a combination of C—HO and C—Hπ(arene) hydrogen bonds, and the sheets are linked in pairs, forming bilayers, by an aromatic π–π stacking interaction.
organic compounds
rac-2-Isopropyl-3-(2-nitrobenzyl)-1,3-thiadiazolin-4-one, C13H16N2O3S, is a rare example of a racemate crystallizing in the space group P212121, with one molecule each of S and R configurations, whose conformations are almost mirror images, within the asymmetric unit. The molecules of S configuration are linked by two C-HO hydrogen bonds into a three-dimensional framework, and the molecules of R configuration are linked by two further C-HO hydrogen bonds into a different type of three-dimensional framework; the two frameworks are linked by a fifth C-HO hydrogen bond.