Ethyl 2-[4-(2-chlorobenzoyl)-2,6-dimethylphenoxy]ethanoate

The asymmetric unit of the title compound, C19H19ClO4, contains two independent molecules. The dihedral angles between the benzene rings are 63.41 (8) and 61.41 (9)°. Adjacent molecules of different types are interconnected in pairs through π–π interactions between their central benzene rings [centroid–centroid separation = 3.801 (2) Å, interplanar spacing = 3.605 (2) Å, centroid shift = 1.204 (2) Å]. Finally, C—H⋯O hydrogen bonds link these dimers into bilayers parallel to (100).

The asymmetric unit of the title compound, C 19 H 19 ClO 4 , contains two independent molecules. The dihedral angles between the benzene rings are 63.41 (8) and 61.41 (9) . Adjacent molecules of different types are interconnected in pairs throughinteractions between their central benzene rings [centroid-centroid separation = 3.801 (2) Å , interplanar spacing = 3.605 (2) Å , centroid shift = 1.204 (2) Å ]. Finally, C-HÁ Á ÁO hydrogen bonds link these dimers into bilayers parallel to (100).  Table 1 Hydrogen-bond geometry (Å , ). Analogues of phenoxy ethanoic acid are considered to be very important compounds in the field of medicinal chemistry, and the compounds were found to have good antifungal activity against pathogenic fungi and posses moderate activity against gram negative bacteria in comparison to standard ciprofloxacin (Dahiya & Kaur 2007). Resent studies shows that changes in the chemical and stereoisomeric structures of phenoxy ethanoic acid alter peroxisome proliferation (Esbenshade et al., 1990). The anti-inflammatory activity results revealed a significant anti-inflammatory activity (up to 63.4%, 62.0%, 64.1% and 62.5% edema inhibition, respectively), as compared to the standard drug diclofenac (67.0%).

Related literature
Pathological investigation has shown that the analogues of phenoxy ethanoic acid compounds have higher anti hyperlipidmeic effect and caused appropriate modulation in HDL levels and some compounds showed a good potential for obesity-associated hyperlipidemia (Khanum et al., 2010).The phenoxy acetic acid analogues show very good antitumor activity on Ehrlich asites tumor cells (Prabhakar et al., 2006) and also show the anti ulcerogenic activity, cyclooxygenase activity, anticonvulsant activity (Sudha et al., 2003) and anti microbial activities (Ma et al., 2011). We were interested in obtaining these type of compounds to evaluate their biological activity; for this purpose, the title compound, [4-(2-chlorobenzoyl)-2,6-dimethylphenoxy].ethanoic acid (I) was synthesized.
The asymmetric unit of (I) comprises two crystallographically independent molecules, A and B,respectively (Fig. 1).
The geometry of both independent molecules indicates a high degree of similarity in terms of bond distances and angles.

Refinement
All H atoms were positioned geometrically and were treated as riding on their parent C atoms, with C-H distances of 0.93-0.97 Å; and with U iso (H) = 1.2U eq (C), except for the methyl groups where U iso (H) = 1.5U eq (C).     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 R-factors(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.