3-(2-Methylphenyl)-2-thioxo-1,3-thiazolidin-4-one

In the title compound, C10H9NOS2, the 1,3-thiazolidine and 2-methylphenyl rings are oriented at a dihedral angle of 84.44 (9)°. In the crystal, an unusual bifurcated C—H⋯(O,π) interaction leads to zigzag chains of molecules.

In the title compound, C 10 H 9 NOS 2 , the 1,3-thiazolidine and 2methylphenyl rings are oriented at a dihedral angle of 84.44 (9) . In the crystal, an unusual bifurcated C-HÁ Á Á(O,) interaction leads to zigzag chains of molecules.

Comment
Rhodanine-based molecules have been popular as small molecule inhibitors of numerous targets such as HCV NS3 protease, aldose reductase, beta-lactamase, UDP-N-acetylmuramate/L-alanine ligase, antidiabetic agents, cathepsin D, and histidine decarboxylase (Cutshall et al., 2005). We herein, report the crystal structure and preparation of the title compound (I, Fig.   1) which is one of the rhodanine derivatives from the series of compounds prepared by our group for beta-lactamase and xanthine oxidase enzyme inhibition studies.

Experimental
The title compound was prepared by a three step reaction procedure. In the first step ortho toluidine aniline (10.7 g, 0.1 mol) and triethylamine (50.5 g, 0.5 mol) were stirred in ethanol (20 ml) followed by dropwise addition of CS 2 (15.2 g, 0.2 mol) while keeping the flask in an ice bath. The precipitate obtained were filtered off and washed with diethyl ether.
In second step, a solution of sodium chloroacetate (11.6 g, 0.1 mol) and chloroacetic acid (18.9 g, 0.2 mol) was prepared in 50 ml distilled water. To this solution the precipitates obtained in first step were added gradually and stirred at 273 K.
This mixture was stirred untill it turned dark yellow.
In third step the yellow mixture was mixed in 140 ml hot (363-368 K) hydrochloric acid (6 N) and stirred for five minutes to obtain colorless crystalline precipitates. These precipitates were recrystalized in chloroform to get the dark yellow needles of (I).

Special details
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating Rfactors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.