N-[5-Methyl-2-(2-nitro­phen­yl)-4-oxo-1,3-thia­zolidin-3-yl]pyridine-3-carboxamide monohydrate

In the title compound, C16H14N4O4S·H2O, the benzene and pyridine rings make a dihedral angle of 85.8 (1)°. Both enanti­omers of the chiral title compound are statistically disordered over the same position in the unit cell. The methyl and carbonyl group attached to the stereogenic center (C5 of the thia­zolidine ring) were therefore refined with common site-occupation factors of 0.531 (9) and 0.469 (9), respectively, for each stereoisomer. In the crystal, inter­molecular N—H⋯O, O—H⋯O and O—H⋯N hydrogen bonds link the mol­ecules, forming a three-dimensional supra­molecular network. The crystal structure further shows π–π stacking inter­actions [centroid–centroid distance = 3.5063 (13) Å] between the pyridine rings

N-[2-(4-Chloro­phen­yl)-5-methyl-4-oxo-1,3-thia­zolidin-3-yl]pyridine-3-carboxamide

The title compound, C16H14ClN3O2S, crystallizes with two mol­ecules in the asymmetric unit. In the 1,3-thia­zolidine rings, the carbonyl O atoms, the S atoms, the methyl groups and the ring carbon attached to the methyl groups are disordered with occupancy ratios of 0.509 (7):0.491 (7) in one mol­ecule and 0.464 (14):0.536 (14) in the other. The crystal structure is stabilized by inter­molecular N—H⋯N, C—H⋯O hydrogen bonds and C—H⋯Cl inter­actions. In addition, there is a π–π stacking inter­action [centroid–centroid distance = 3.794 (3) Å] between the benzene and pyridine rings