N-[5-Methyl-2-(2-nitro-phen-yl)-4-oxo-1,3-thia-zolidin-3-yl]pyridine-3-carboxamide monohydrate

rac-cis-5-Methyl-2,3-diphenyl-1,3-thiazolidin-4-one

In the racemic title compound, C16H15NOS, the thiazolidine ring adopts an envelope conformation, with the S atom as the flap. The dihedral angles between the heterocycle (all atoms) and pendant C– and N-bound benzene rings are 69.75 (14) and 56.56 (11)°, respectively; the aromatic rings are almost orthogonal to each other, with a dihedral angle of 76.04 (14)° between them. In the crystal, molecules are linked by weak C—H...O hydrogen bonds to generate [101] chains, with alternating molecules being enantiomers. A weak C—H...π interaction is also observed.

Stereochemical Investigations of Diastereomeric N-[2-(Aryl)-5-methyl-4-oxo-1,3-thiazolidine-3-yl]-pyridine-3-carboxamides by Nuclear Magnetic Resonance Spectroscopy (1D and 2D)

Some new N-[2-(aryl)-5-methyl-4-oxo-1,3-thiazolidine-3-yl]-pyridine-3-carboxamides were synthesized and their structures were investigated by IR, NMR (1H, 13C, and 2D), and mass spectra. The presence of C-2 and C-5 stereogenic centers on the thiazolidinone ring resulted in diastereoisomeric pairs. The configurations of two stereogenic centers were assigned based upon 1H NMR analysis of coupling constants and 2D nuclear overhauser enhancement spectroscopy (NOESY) experiment. Resolution of the diastereoisomers was performed by high performance liquid chromatography (HPLC) using a chiral stationary phase.

5-Chloro-N-{4-oxo-2-[4-(trifluoro-meth-yl)phen-yl]-1,3-thia-zolidin-3-yl}-3-phenyl-1H-indole-2-carboxamide

In the title compound, C(25)H(17)ClF(3)N(3)O(2)S, the five-membered 1,3-thia-zolidine ring adopts a twist conformation. The three F atoms of the CF(3) group are disordered over two sets of sites with refined occupancies of 0.542 (18) and 0.458 (18). In the nine-membered 1H-indoline ring system, the 1H-pyrrole ring forms a dihedral angle of 4.7 (2)° with the benzene ring, while it is twisted at an angle of 46.5 (2)° with respect to the attached phenyl ring. The dihedral angle between the phenyl and trifluoro-methyl-substituted benzene rings is 56.0 (2)°. In the crystal, N-H⋯O hydrogen bonds connect the mol-ecules into a three-dimensional network. In addition, weak C-H⋯O hydrogen bonds and weak C-H⋯π inter-actions are observed.