organic compounds
2-(2,6-Dimethoxyphenyl)-5-hydroxy-7-methoxy-4H-1-benzopyran-4-one
aDepartment of Physics, S. V. University, Tirupati 517 502, India, bDepartment of Chemistry, S. V. University, Tirupati 517 502, India, and cCentre of Material Characterisation, National Chemical Laboratory, Pune 411 008, India
*Correspondence e-mail: mkphysvu@yahoo.co.in
In the title compound, C18H16O6, the dimethoxyphenyl ring is rotated by 61.8 (1)° from the plane of the benzopyran system. The molecule is stabilized by an intramolecular O—H⋯O hydrogen bond.
Related literature
The title compound, along with a terpinoid and six other Andrographis peniculata Nees (Reddy et al., 2003), a herb widely distributed in the plains of India and Sri Lanka (Gamble, 1956). In traditional Indian medicine, the whole plant of A. peniculata is extensively used in the treatment of dyspepsia, dysentery, malaria, respiratory infections and as an antidote for snake bites, see: Kirtikar & Basu (1975); Chopra et al. (1980).
was isolated from the roots and the aerial parts ofExperimental
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2001); cell SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1999); software used to prepare material for publication: enCIFer (Allen et al., 2004) and PARST (Nardelli, 1995).
Supporting information
10.1107/S1600536809032383/hg2533sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809032383/hg2533Isup2.hkl
The shade dried and powdered roots of whole plant of A. paniculata Nees (3 kg) was successively extracted with n-hexane, Me2CO and MeOH. The acetone extract on purification over a silica gel column using n-hexane EtoAc step gradients yielded 18 mg of the title compound with a m.p. of 196–198°C and recrystalized by slow evaporation from a hexane solution.
All H atoms were placed in calculated positions, with C—H = 0.93Å (aromatic H) or 0.96Å (methyl H) or 0.82Å (oxygen H) and included in the final cycles of
using a riding model, with Uiso(H) = 1.2Ueq (C-aromatic) or Uiso(H) = 1.5Ueq for methyl and oxygen atoms.Data collection: SMART (Bruker, 2001); cell
SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1999); software used to prepare material for publication: enCIFer (Allen et al., 2004) and PARST (Nardelli, 1995).Fig. 1. View of the molecule showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented by circles of arbitrary radius. |
C18H16O6 | F(000) = 688 |
Mr = 328.31 | Dx = 1.425 Mg m−3 Dm = 1.42 Mg m−3 Dm measured by none |
Monoclinic, P21/n | Melting point: 469 K |
Hall symbol: -P 2yn | Mo Kα radiation, λ = 0.71073 Å |
a = 11.003 (7) Å | Cell parameters from 25 reflections |
b = 11.015 (7) Å | θ = 2–25° |
c = 13.734 (9) Å | µ = 0.11 mm−1 |
β = 113.159 (10)° | T = 295 K |
V = 1530.4 (17) Å3 | Needle, colourless |
Z = 4 | 0.69 × 0.37 × 0.36 mm |
Bruker SMART CCD area-detector diffractometer | 2675 independent reflections |
Radiation source: fine-focus sealed tube | 2300 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.023 |
Detector resolution: 0 pixels mm-1 | θmax = 25.0°, θmin = 2.5° |
ω scans | h = −7→13 |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | k = −13→13 |
Tmin = 0.929, Tmax = 0.969 | l = −16→16 |
7431 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.037 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.096 | H-atom parameters constrained |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0462P)2 + 0.3516P] where P = (Fo2 + 2Fc2)/3 |
2675 reflections | (Δ/σ)max < 0.001 |
221 parameters | Δρmax = 0.17 e Å−3 |
0 restraints | Δρmin = −0.18 e Å−3 |
C18H16O6 | V = 1530.4 (17) Å3 |
Mr = 328.31 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 11.003 (7) Å | µ = 0.11 mm−1 |
b = 11.015 (7) Å | T = 295 K |
c = 13.734 (9) Å | 0.69 × 0.37 × 0.36 mm |
β = 113.159 (10)° |
Bruker SMART CCD area-detector diffractometer | 2675 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | 2300 reflections with I > 2σ(I) |
Tmin = 0.929, Tmax = 0.969 | Rint = 0.023 |
7431 measured reflections |
R[F2 > 2σ(F2)] = 0.037 | 0 restraints |
wR(F2) = 0.096 | H-atom parameters constrained |
S = 1.04 | Δρmax = 0.17 e Å−3 |
2675 reflections | Δρmin = −0.18 e Å−3 |
221 parameters |
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 F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is ?t relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.95634 (9) | 0.63933 (8) | 0.16154 (8) | 0.0376 (3) | |
C2 | 0.97394 (14) | 0.75775 (13) | 0.14376 (12) | 0.0361 (3) | |
C3 | 1.06401 (15) | 0.79404 (13) | 0.10773 (12) | 0.0412 (4) | |
H3 | 1.0720 | 0.8764 | 0.0967 | 0.049* | |
C4 | 1.14884 (15) | 0.71009 (13) | 0.08555 (12) | 0.0391 (3) | |
O4 | 1.23188 (12) | 0.74190 (10) | 0.04933 (10) | 0.0526 (3) | |
C5 | 1.13251 (14) | 0.58600 (13) | 0.10870 (11) | 0.0350 (3) | |
C6 | 1.21312 (15) | 0.49245 (14) | 0.09621 (12) | 0.0393 (3) | |
O6 | 1.30566 (12) | 0.52024 (11) | 0.05872 (11) | 0.0560 (3) | |
H6 | 1.3026 | 0.5931 | 0.0458 | 0.084* | |
C7 | 1.19766 (16) | 0.37579 (14) | 0.12164 (12) | 0.0436 (4) | |
H7 | 1.2524 | 0.3151 | 0.1146 | 0.052* | |
C8 | 1.09978 (15) | 0.34760 (13) | 0.15815 (12) | 0.0403 (3) | |
O8 | 1.09338 (12) | 0.22951 (9) | 0.18118 (10) | 0.0537 (3) | |
C9 | 1.01709 (14) | 0.43571 (13) | 0.16945 (11) | 0.0375 (3) | |
H9 | 0.9506 | 0.4162 | 0.1926 | 0.045* | |
C5A | 1.03645 (13) | 0.55351 (13) | 0.14532 (11) | 0.0333 (3) | |
C10 | 0.9930 (2) | 0.19296 (17) | 0.21541 (17) | 0.0638 (5) | |
H10A | 1.0044 | 0.2346 | 0.2798 | 0.096* | |
H10B | 0.9987 | 0.1070 | 0.2278 | 0.096* | |
H10C | 0.9080 | 0.2125 | 0.1618 | 0.096* | |
C1' | 0.88314 (14) | 0.83990 (13) | 0.16728 (12) | 0.0376 (3) | |
C2' | 0.88837 (14) | 0.85308 (13) | 0.26936 (12) | 0.0396 (4) | |
O2' | 0.97735 (11) | 0.78129 (10) | 0.34356 (8) | 0.0467 (3) | |
C3' | 0.80767 (16) | 0.93686 (15) | 0.28990 (14) | 0.0479 (4) | |
H3' | 0.8119 | 0.9467 | 0.3584 | 0.057* | |
C4' | 0.72169 (17) | 1.00504 (15) | 0.20869 (15) | 0.0521 (4) | |
H4' | 0.6680 | 1.0613 | 0.2231 | 0.063* | |
C5' | 0.71262 (16) | 0.99273 (14) | 0.10730 (14) | 0.0493 (4) | |
H5' | 0.6523 | 1.0388 | 0.0530 | 0.059* | |
C6' | 0.79435 (15) | 0.91074 (14) | 0.08648 (13) | 0.0426 (4) | |
O6' | 0.79624 (13) | 0.89242 (11) | −0.00985 (9) | 0.0594 (3) | |
C12 | 0.70572 (18) | 0.95611 (16) | −0.09779 (14) | 0.0551 (4) | |
H12A | 0.6172 | 0.9317 | −0.1097 | 0.083* | |
H12B | 0.7232 | 0.9381 | −0.1595 | 0.083* | |
H12C | 0.7152 | 1.0418 | −0.0840 | 0.083* | |
C11 | 0.99169 (19) | 0.79582 (17) | 0.44992 (13) | 0.0557 (5) | |
H11A | 1.0145 | 0.8785 | 0.4713 | 0.084* | |
H11B | 1.0603 | 0.7430 | 0.4947 | 0.084* | |
H11C | 0.9100 | 0.7757 | 0.4558 | 0.084* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0400 (6) | 0.0327 (5) | 0.0456 (6) | 0.0029 (4) | 0.0227 (5) | −0.0012 (4) |
C2 | 0.0384 (8) | 0.0313 (7) | 0.0373 (8) | 0.0008 (6) | 0.0135 (6) | −0.0020 (6) |
C3 | 0.0455 (9) | 0.0317 (8) | 0.0498 (9) | 0.0011 (6) | 0.0223 (7) | 0.0006 (7) |
C4 | 0.0404 (8) | 0.0408 (8) | 0.0390 (8) | −0.0015 (7) | 0.0187 (7) | −0.0003 (7) |
O4 | 0.0583 (7) | 0.0444 (6) | 0.0717 (8) | −0.0006 (5) | 0.0435 (7) | 0.0037 (6) |
C5 | 0.0362 (7) | 0.0364 (8) | 0.0322 (7) | 0.0005 (6) | 0.0132 (6) | −0.0025 (6) |
C6 | 0.0388 (8) | 0.0418 (8) | 0.0404 (8) | 0.0018 (6) | 0.0188 (7) | −0.0038 (7) |
O6 | 0.0579 (7) | 0.0495 (7) | 0.0795 (8) | 0.0053 (6) | 0.0474 (7) | 0.0004 (6) |
C7 | 0.0447 (9) | 0.0378 (8) | 0.0496 (9) | 0.0081 (7) | 0.0200 (7) | −0.0040 (7) |
C8 | 0.0442 (8) | 0.0336 (8) | 0.0394 (8) | 0.0001 (7) | 0.0127 (7) | −0.0025 (7) |
O8 | 0.0639 (8) | 0.0317 (6) | 0.0708 (8) | 0.0032 (5) | 0.0323 (7) | 0.0043 (5) |
C9 | 0.0387 (8) | 0.0360 (8) | 0.0395 (8) | −0.0017 (6) | 0.0172 (7) | −0.0011 (6) |
C5A | 0.0340 (7) | 0.0334 (7) | 0.0317 (7) | 0.0024 (6) | 0.0120 (6) | −0.0037 (6) |
C10 | 0.0678 (12) | 0.0427 (10) | 0.0818 (13) | −0.0062 (9) | 0.0305 (11) | 0.0124 (10) |
C1' | 0.0361 (8) | 0.0315 (7) | 0.0463 (8) | −0.0001 (6) | 0.0176 (7) | −0.0041 (7) |
C2' | 0.0389 (8) | 0.0347 (8) | 0.0493 (9) | −0.0009 (6) | 0.0217 (7) | 0.0001 (7) |
O2' | 0.0522 (6) | 0.0483 (7) | 0.0443 (6) | 0.0107 (5) | 0.0242 (5) | 0.0017 (5) |
C3' | 0.0542 (10) | 0.0445 (9) | 0.0574 (10) | 0.0042 (8) | 0.0353 (9) | −0.0015 (8) |
C4' | 0.0529 (10) | 0.0408 (9) | 0.0753 (12) | 0.0102 (8) | 0.0388 (10) | 0.0004 (9) |
C5' | 0.0445 (9) | 0.0408 (9) | 0.0623 (11) | 0.0094 (7) | 0.0207 (8) | 0.0033 (8) |
C6' | 0.0418 (8) | 0.0356 (8) | 0.0487 (9) | 0.0010 (7) | 0.0162 (7) | −0.0045 (7) |
O6' | 0.0695 (8) | 0.0590 (8) | 0.0417 (6) | 0.0255 (6) | 0.0131 (6) | −0.0009 (6) |
C12 | 0.0575 (10) | 0.0465 (10) | 0.0509 (10) | 0.0044 (8) | 0.0101 (8) | 0.0066 (8) |
C11 | 0.0676 (11) | 0.0585 (11) | 0.0481 (10) | 0.0069 (9) | 0.0301 (9) | 0.0014 (8) |
O1—C2 | 1.3549 (19) | C10—H10B | 0.9600 |
O1—C5A | 1.3692 (17) | C10—H10C | 0.9600 |
C2—C3 | 1.331 (2) | C1'—C2' | 1.388 (2) |
C2—C1' | 1.475 (2) | C1'—C6' | 1.394 (2) |
C3—C4 | 1.429 (2) | C2'—O2' | 1.3555 (19) |
C3—H3 | 0.9300 | C2'—C3' | 1.384 (2) |
C4—O4 | 1.2500 (18) | O2'—C11 | 1.415 (2) |
C4—C5 | 1.431 (2) | C3'—C4' | 1.369 (2) |
C5—C5A | 1.384 (2) | C3'—H3' | 0.9300 |
C5—C6 | 1.413 (2) | C4'—C5' | 1.363 (3) |
C6—O6 | 1.3445 (18) | C4'—H4' | 0.9300 |
C6—C7 | 1.360 (2) | C5'—C6' | 1.381 (2) |
O6—H6 | 0.8200 | C5'—H5' | 0.9300 |
C7—C8 | 1.390 (2) | C6'—O6' | 1.346 (2) |
C7—H7 | 0.9300 | O6'—C12 | 1.413 (2) |
C8—O8 | 1.347 (2) | C12—H12A | 0.9600 |
C8—C9 | 1.380 (2) | C12—H12B | 0.9600 |
O8—C10 | 1.418 (2) | C12—H12C | 0.9600 |
C9—C5A | 1.376 (2) | C11—H11A | 0.9600 |
C9—H9 | 0.9300 | C11—H11B | 0.9600 |
C10—H10A | 0.9600 | C11—H11C | 0.9600 |
C2—O1—C5A | 119.25 (11) | H10A—C10—H10C | 109.5 |
C3—C2—O1 | 122.42 (13) | H10B—C10—H10C | 109.5 |
C3—C2—C1' | 124.37 (14) | C2'—C1'—C6' | 118.90 (13) |
O1—C2—C1' | 113.21 (12) | C2'—C1'—C2 | 121.52 (13) |
C2—C3—C4 | 121.93 (14) | C6'—C1'—C2 | 119.49 (13) |
C2—C3—H3 | 119.0 | O2'—C2'—C3' | 124.56 (14) |
C4—C3—H3 | 119.0 | O2'—C2'—C1' | 115.41 (13) |
O4—C4—C3 | 122.98 (14) | C3'—C2'—C1' | 120.03 (14) |
O4—C4—C5 | 122.11 (13) | C2'—O2'—C11 | 117.66 (12) |
C3—C4—C5 | 114.91 (13) | C4'—C3'—C2' | 119.54 (15) |
C5A—C5—C6 | 117.44 (13) | C4'—C3'—H3' | 120.2 |
C5A—C5—C4 | 120.55 (13) | C2'—C3'—H3' | 120.2 |
C6—C5—C4 | 122.00 (13) | C5'—C4'—C3' | 121.82 (15) |
O6—C6—C7 | 120.24 (13) | C5'—C4'—H4' | 119.1 |
O6—C6—C5 | 119.10 (14) | C3'—C4'—H4' | 119.1 |
C7—C6—C5 | 120.66 (14) | C4'—C5'—C6' | 118.98 (16) |
C6—O6—H6 | 109.5 | C4'—C5'—H5' | 120.5 |
C6—C7—C8 | 119.78 (14) | C6'—C5'—H5' | 120.5 |
C6—C7—H7 | 120.1 | O6'—C6'—C5' | 124.35 (15) |
C8—C7—H7 | 120.1 | O6'—C6'—C1' | 114.93 (13) |
O8—C8—C9 | 123.71 (14) | C5'—C6'—C1' | 120.72 (15) |
O8—C8—C7 | 114.82 (13) | C6'—O6'—C12 | 119.16 (13) |
C9—C8—C7 | 121.46 (14) | O6'—C12—H12A | 109.5 |
C8—O8—C10 | 118.13 (13) | O6'—C12—H12B | 109.5 |
C5A—C9—C8 | 117.69 (14) | H12A—C12—H12B | 109.5 |
C5A—C9—H9 | 121.2 | O6'—C12—H12C | 109.5 |
C8—C9—H9 | 121.2 | H12A—C12—H12C | 109.5 |
O1—C5A—C9 | 116.19 (13) | H12B—C12—H12C | 109.5 |
O1—C5A—C5 | 120.86 (13) | O2'—C11—H11A | 109.5 |
C9—C5A—C5 | 122.94 (13) | O2'—C11—H11B | 109.5 |
O8—C10—H10A | 109.5 | H11A—C11—H11B | 109.5 |
O8—C10—H10B | 109.5 | O2'—C11—H11C | 109.5 |
H10A—C10—H10B | 109.5 | H11A—C11—H11C | 109.5 |
O8—C10—H10C | 109.5 | H11B—C11—H11C | 109.5 |
C5A—O1—C2—C3 | 2.1 (2) | C6—C5—C5A—O1 | 178.64 (12) |
C5A—O1—C2—C1' | −178.43 (12) | C4—C5—C5A—O1 | −0.9 (2) |
O1—C2—C3—C4 | −0.2 (2) | C6—C5—C5A—C9 | 0.0 (2) |
C1'—C2—C3—C4 | −179.53 (14) | C4—C5—C5A—C9 | −179.56 (14) |
C2—C3—C4—O4 | 178.26 (15) | C3—C2—C1'—C2' | −115.93 (18) |
C2—C3—C4—C5 | −2.2 (2) | O1—C2—C1'—C2' | 64.66 (18) |
O4—C4—C5—C5A | −177.77 (14) | C3—C2—C1'—C6' | 60.8 (2) |
C3—C4—C5—C5A | 2.7 (2) | O1—C2—C1'—C6' | −118.64 (15) |
O4—C4—C5—C6 | 2.7 (2) | C6'—C1'—C2'—O2' | −179.85 (13) |
C3—C4—C5—C6 | −176.84 (14) | C2—C1'—C2'—O2' | −3.1 (2) |
C5A—C5—C6—O6 | 178.63 (13) | C6'—C1'—C2'—C3' | −1.0 (2) |
C4—C5—C6—O6 | −1.8 (2) | C2—C1'—C2'—C3' | 175.73 (14) |
C5A—C5—C6—C7 | −1.4 (2) | C3'—C2'—O2'—C11 | −2.1 (2) |
C4—C5—C6—C7 | 178.17 (15) | C1'—C2'—O2'—C11 | 176.67 (14) |
O6—C6—C7—C8 | −178.61 (14) | O2'—C2'—C3'—C4' | 179.69 (15) |
C5—C6—C7—C8 | 1.4 (2) | C1'—C2'—C3'—C4' | 0.9 (2) |
C6—C7—C8—O8 | −179.87 (14) | C2'—C3'—C4'—C5' | 0.2 (3) |
C6—C7—C8—C9 | 0.0 (2) | C3'—C4'—C5'—C6' | −1.2 (3) |
C9—C8—O8—C10 | 2.3 (2) | C4'—C5'—C6'—O6' | −178.63 (15) |
C7—C8—O8—C10 | −177.86 (15) | C4'—C5'—C6'—C1' | 1.2 (2) |
O8—C8—C9—C5A | 178.53 (14) | C2'—C1'—C6'—O6' | 179.76 (13) |
C7—C8—C9—C5A | −1.3 (2) | C2—C1'—C6'—O6' | 3.0 (2) |
C2—O1—C5A—C9 | 177.17 (13) | C2'—C1'—C6'—C5' | −0.1 (2) |
C2—O1—C5A—C5 | −1.57 (19) | C2—C1'—C6'—C5' | −176.86 (14) |
C8—C9—C5A—O1 | −177.40 (12) | C5'—C6'—O6'—C12 | −2.9 (2) |
C8—C9—C5A—C5 | 1.3 (2) | C1'—C6'—O6'—C12 | 177.24 (14) |
Experimental details
Crystal data | |
Chemical formula | C18H16O6 |
Mr | 328.31 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 295 |
a, b, c (Å) | 11.003 (7), 11.015 (7), 13.734 (9) |
β (°) | 113.159 (10) |
V (Å3) | 1530.4 (17) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.11 |
Crystal size (mm) | 0.69 × 0.37 × 0.36 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2001) |
Tmin, Tmax | 0.929, 0.969 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7431, 2675, 2300 |
Rint | 0.023 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.037, 0.096, 1.04 |
No. of reflections | 2675 |
No. of parameters | 221 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.17, −0.18 |
Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1999), enCIFer (Allen et al., 2004) and PARST (Nardelli, 1995).
Acknowledgements
MK thanks the University Grants Commission, New Delhi, for financial support as a major project.
References
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The title compound along with a terpinoid and six other flavonoids were isolated from the roots and the aerial parts of Andrographis peniculata Nees (Reddy et al., 2003), an erect herb widely distributed in the plains throughout India and Srilanka (Gamble, 1956). In traditional Indian medicine the whole plant of A. peniculata is extensively used in the treatment of dyspepsia, dysentery, malaria, respiratory infections and as an antidote for snake bites (Kirtikar & Basu, 1975; Chopra et al., 1980). As a part of our ongoing investigation on medicinal plants, we report the structure of the title compound (I) (Fig.1).
The benzopyran ring is slightly planar with a maximum deviation from the plane of 0.034 (1) Å. The dihedral angle between the least-squares planes of the phenyl ring and the benzopyran moiety is 61.8 (1)°. The non planarity of the phenolic ring is due to the presence of the steric hindrance caused by 2',6' dioxygenation resulting the decrease in the conjugation of the phenyl ring with the carbonyl group. The absence of conjugation means that there will be more delocalization of π-electrons in C2, C3, C4, and O4 unit. The C2–C1' bond length (1.475 (2)Å) is within the 3σ of the average 4sp2-4sp3 bond distance of 1.48 Å.