Methyl (E)-2-({2-[(E)-(hydroxyimino)methyl]phenoxy}methyl)-3-phenylacrylate

In the title compound, C18H17NO4, the hydroxyethanimine group is essentially coplanar with the ring to which it is attached [C—C—N—O torsion angle = 179.94 (14)°]. The molecules are linked into cyclic centrosymmetric R 2 2(6) dimers via O—H⋯N hydrogen bonds and the crystal packing is further stabilized by C—H⋯O interactions.

In the title compound, C 18 H 17 NO 4 , the hydroxyethanimine group is essentially coplanar with the ring to which it is attached [C-C-N-O torsion angle = 179.94 (14) ]. The molecules are linked into cyclic centrosymmetric R 2 2 (6) dimers via O-HÁ Á ÁN hydrogen bonds and the crystal packing is further stabilized by C-HÁ Á ÁO interactions.

Experimental
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT5745).
used in coordination and analytical chemistry (Chaudhuri, 2003). Some naturally occurring caffeic acids and their esters attract much attention in biology and medicine (Hwang et al., 2001;Altug et al., 2008).These compounds show antiviral, antibacterial, vasoactive, antiatherogenic, antiproliferative, antioxidant and antiinflammatory properties (Atik et al.,2006;Padinchare et al., 2001;Ates et al., 2006). Against this background,and in order to obtain detailed information on molecular conformations in the solid state, an X-ray study of the title compound was carried out and the results are presented here. X-Ray analysis confirms the molecular structure and atom connectivity as illustrated in Fig

Refinement
Hydrogen atoms were set to calculated positions and refined as riding on their parent atoms with O-H = 0.82Å and C-H ranging from 0.93Å to 0.97Å and U(H) set to 1.2 U eq (C) or 1.5 U eq (C methyl , O).  (Farrugia, 1997); software used to prepare material for publication: PLATON (Spek, 2009).

Figure 1
The molecular structure of the title compound, showing 30% probability displacement ellipsoids for H atoms.   where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.21 e Å −3 Δρ min = −0.17 e Å −3 Extinction correction: SHELXL97 (Sheldrick, 2008), Fc * =kFc[1+0.001xFc 2 λ 3 /sin(2θ)] -1/4 Extinction coefficient: 0.0173 (18) Special details Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. 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.