Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807017837/hb2364sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807017837/hb2364Isup2.hkl |
CCDC reference: 647601
The title compound was synthesized according to the literature procedure of Cignarella et al. (1992). Crystals of (I) suitable for X-ray crystallographic analysis were recrystallized from dichloromethane at 277 K.
The H atoms were placed in idealized positions, with C—H = 0.93–0.97 Å and N—H = 0.86 Å, and refined as riding, with Uiso(H) = 1.2Ueq(C,N).
Flavonoids, occurring widely throughout the plant kingdom, are one of the most representative families of plant secondary metabolites and display a remarkable
spectrum of biological activities. They are used as a synthetic lead for drug discovery (Ren et al., 2003). The title compound, (I) (Fig. 1), is an important intermediate for the synthesis of flavonoid derivatives.
Compound (I) contains two independent molecules (A and B) in the asymmetric unit, with bond lengths and angles within normal ranges (Allen et al., 1987). The six-membered pyran ring adopts a half-chair conformation in molecule A (atoms C1/C6–C9/O3) and an envelope conformation in molecule B (atoms C12/C17–C20/O1). The fused heterocyclic ring (atoms C7/C8/C10/C11/N4/N3 in A; atoms C18/C19/C21/C22/N1/N2 in B) adopts a sofa conformation in both molecules.
The structure is stabilized by weak N—H···O hydrogen-bonding interactions (Table 1). The hydrogen bonds link pairs of independent molecules into dimers, while the N—H···O interactions link pairs of dimers into chains in the bc plane. A short C—H···O contact is also present. Further stability is provided
by offset π–π stacking interactions between adjacent C1–C6 and C12–C17 benzene rings. The centroid–centroid distance is 3.860 (5) Å.
For background literature, see Potts & Dery (1986), Ren et al. (2003) and Wang & Tunge (2006).
For related literature, see: Allen et al. (1987); Cignarella et al. (1992).
Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXTL (Bruker, 2001).
C11H10N2O2 | F(000) = 848 |
Mr = 202.21 | Dx = 1.405 Mg m−3 |
Orthorhombic, Pca21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2c -2ac | Cell parameters from 1006 reflections |
a = 7.6838 (10) Å | θ = 2.4–19.8° |
b = 7.4659 (9) Å | µ = 0.10 mm−1 |
c = 33.322 (4) Å | T = 292 K |
V = 1911.6 (4) Å3 | Block, colourless |
Z = 8 | 0.40 × 0.30 × 0.10 mm |
Bruker SMART 4K CCD area-detector diffractometer | 1906 independent reflections |
Radiation source: fine-focus sealed tube | 1211 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.057 |
ω scans | θmax = 26.0°, θmin = 1.2° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −9→9 |
Tmin = 0.961, Tmax = 0.990 | k = −8→9 |
9576 measured reflections | l = −41→36 |
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)] = 0.057 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.179 | H-atom parameters constrained |
S = 1.00 | w = 1/[σ2(Fo2) + (0.1059P)2] where P = (Fo2 + 2Fc2)/3 |
1906 reflections | (Δ/σ)max < 0.001 |
271 parameters | Δρmax = 0.19 e Å−3 |
1 restraint | Δρmin = −0.18 e Å−3 |
C11H10N2O2 | V = 1911.6 (4) Å3 |
Mr = 202.21 | Z = 8 |
Orthorhombic, Pca21 | Mo Kα radiation |
a = 7.6838 (10) Å | µ = 0.10 mm−1 |
b = 7.4659 (9) Å | T = 292 K |
c = 33.322 (4) Å | 0.40 × 0.30 × 0.10 mm |
Bruker SMART 4K CCD area-detector diffractometer | 1906 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 1211 reflections with I > 2σ(I) |
Tmin = 0.961, Tmax = 0.990 | Rint = 0.057 |
9576 measured reflections |
R[F2 > 2σ(F2)] = 0.057 | 1 restraint |
wR(F2) = 0.179 | H-atom parameters constrained |
S = 1.00 | Δρmax = 0.19 e Å−3 |
1906 reflections | Δρmin = −0.18 e Å−3 |
271 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 not 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 | 0.0527 (7) | 0.8659 (5) | 0.46763 (15) | 0.0732 (14) | |
O2 | 0.3726 (8) | 0.6504 (6) | 0.30959 (14) | 0.0791 (15) | |
N1 | 0.2055 (7) | 0.4405 (7) | 0.39697 (15) | 0.0498 (13) | |
N2 | 0.2621 (11) | 0.4758 (7) | 0.3587 (2) | 0.0586 (18) | |
H2A | 0.2644 | 0.3867 | 0.3423 | 0.070* | |
C12 | 0.0380 (9) | 0.6931 (10) | 0.4825 (2) | 0.0565 (17) | |
C13 | −0.0268 (11) | 0.6771 (12) | 0.5207 (2) | 0.069 (2) | |
H13 | −0.0574 | 0.7775 | 0.5357 | 0.083* | |
C14 | −0.0450 (13) | 0.5037 (13) | 0.5364 (3) | 0.077 (3) | |
H14 | −0.0935 | 0.4879 | 0.5617 | 0.093* | |
C15 | 0.0090 (12) | 0.3538 (12) | 0.5143 (2) | 0.067 (2) | |
H15 | −0.0014 | 0.2394 | 0.5250 | 0.081* | |
C16 | 0.0767 (10) | 0.3773 (10) | 0.4771 (2) | 0.0600 (19) | |
H16 | 0.1156 | 0.2770 | 0.4632 | 0.072* | |
C17 | 0.0910 (8) | 0.5450 (10) | 0.45849 (18) | 0.0461 (16) | |
C18 | 0.1612 (8) | 0.5739 (9) | 0.41872 (17) | 0.0483 (15) | |
C19 | 0.1671 (11) | 0.7619 (8) | 0.4037 (2) | 0.070 (2) | |
H19 | 0.0555 | 0.7799 | 0.3901 | 0.083* | |
C20 | 0.1670 (11) | 0.8928 (8) | 0.4369 (2) | 0.074 (2) | |
H20A | 0.2834 | 0.8961 | 0.4482 | 0.089* | |
H20B | 0.1440 | 1.0101 | 0.4256 | 0.089* | |
C21 | 0.2986 (12) | 0.7876 (8) | 0.3726 (2) | 0.080 (2) | |
H21A | 0.4107 | 0.8052 | 0.3854 | 0.096* | |
H21B | 0.2713 | 0.8960 | 0.3579 | 0.096* | |
C22 | 0.3133 (10) | 0.6356 (8) | 0.34363 (18) | 0.0614 (18) | |
O3 | 0.6970 (7) | 0.3665 (6) | 0.15967 (16) | 0.0803 (15) | |
O4 | 0.3727 (8) | 0.1510 (6) | 0.31826 (13) | 0.0788 (15) | |
N3 | 0.5429 (7) | −0.0626 (7) | 0.23097 (16) | 0.0487 (13) | |
N4 | 0.4795 (11) | −0.0232 (7) | 0.26994 (17) | 0.0588 (19) | |
H4A | 0.4693 | −0.1125 | 0.2860 | 0.071* | |
C1 | 0.7049 (9) | 0.1930 (9) | 0.1460 (2) | 0.0535 (17) | |
C2 | 0.7724 (11) | 0.1683 (11) | 0.1079 (2) | 0.064 (2) | |
H2 | 0.8062 | 0.2672 | 0.0928 | 0.076* | |
C3 | 0.7898 (13) | 0.0023 (9) | 0.0922 (2) | 0.059 (2) | |
H3 | 0.8326 | −0.0114 | 0.0663 | 0.071* | |
C4 | 0.7455 (11) | −0.1456 (10) | 0.1141 (2) | 0.060 (2) | |
H4 | 0.7629 | −0.2600 | 0.1038 | 0.072* | |
C5 | 0.6731 (8) | −0.1215 (9) | 0.15232 (19) | 0.0497 (16) | |
H5 | 0.6402 | −0.2212 | 0.1672 | 0.060* | |
C6 | 0.6500 (8) | 0.0464 (10) | 0.16813 (18) | 0.0447 (14) | |
C7 | 0.5879 (8) | 0.0760 (7) | 0.20934 (18) | 0.0455 (14) | |
C8 | 0.5825 (11) | 0.2660 (9) | 0.2245 (2) | 0.0686 (19) | |
H8 | 0.6940 | 0.2851 | 0.2381 | 0.082* | |
C9 | 0.5791 (12) | 0.3946 (7) | 0.1915 (2) | 0.075 (2) | |
H9A | 0.4624 | 0.3958 | 0.1804 | 0.090* | |
H9B | 0.6011 | 0.5126 | 0.2026 | 0.090* | |
C10 | 0.4477 (12) | 0.2895 (8) | 0.2557 (2) | 0.078 (2) | |
H10A | 0.3362 | 0.3079 | 0.2427 | 0.094* | |
H10B | 0.4742 | 0.3968 | 0.2710 | 0.094* | |
C11 | 0.4322 (9) | 0.1362 (8) | 0.28399 (18) | 0.0553 (17) |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.097 (4) | 0.052 (3) | 0.070 (3) | 0.009 (2) | 0.022 (3) | −0.017 (2) |
O2 | 0.130 (4) | 0.053 (2) | 0.054 (3) | 0.000 (3) | 0.020 (3) | 0.005 (2) |
N1 | 0.072 (4) | 0.044 (3) | 0.034 (3) | 0.002 (3) | −0.003 (2) | −0.002 (2) |
N2 | 0.088 (5) | 0.037 (3) | 0.051 (4) | −0.006 (3) | −0.015 (3) | 0.000 (2) |
C12 | 0.058 (4) | 0.059 (4) | 0.052 (4) | −0.002 (3) | 0.003 (3) | −0.016 (3) |
C13 | 0.065 (5) | 0.076 (5) | 0.066 (5) | −0.011 (4) | 0.013 (4) | −0.022 (4) |
C14 | 0.052 (6) | 0.115 (9) | 0.066 (6) | −0.003 (4) | −0.011 (4) | −0.013 (4) |
C15 | 0.063 (5) | 0.082 (6) | 0.057 (5) | 0.006 (4) | 0.002 (4) | 0.008 (4) |
C16 | 0.065 (5) | 0.058 (4) | 0.056 (5) | 0.005 (4) | −0.011 (4) | 0.004 (4) |
C17 | 0.047 (4) | 0.050 (3) | 0.041 (4) | 0.018 (3) | 0.000 (3) | −0.006 (3) |
C18 | 0.051 (4) | 0.056 (4) | 0.037 (3) | 0.002 (3) | 0.002 (3) | −0.004 (3) |
C19 | 0.105 (6) | 0.041 (4) | 0.062 (4) | 0.005 (3) | 0.010 (4) | −0.002 (3) |
C20 | 0.107 (6) | 0.056 (4) | 0.060 (4) | 0.014 (4) | 0.015 (4) | −0.009 (3) |
C21 | 0.133 (7) | 0.047 (4) | 0.059 (4) | −0.008 (4) | 0.035 (5) | 0.000 (3) |
C22 | 0.093 (6) | 0.053 (4) | 0.038 (3) | 0.004 (4) | 0.003 (4) | −0.005 (3) |
O3 | 0.109 (4) | 0.056 (3) | 0.075 (3) | −0.009 (3) | 0.031 (3) | 0.011 (2) |
O4 | 0.143 (5) | 0.050 (2) | 0.043 (2) | 0.006 (3) | 0.025 (3) | −0.001 (2) |
N3 | 0.065 (4) | 0.040 (3) | 0.041 (3) | 0.001 (3) | 0.002 (2) | 0.003 (2) |
N4 | 0.094 (5) | 0.045 (3) | 0.037 (3) | −0.005 (3) | 0.032 (3) | 0.006 (2) |
C1 | 0.053 (4) | 0.049 (4) | 0.059 (4) | −0.003 (3) | 0.004 (3) | 0.008 (3) |
C2 | 0.065 (5) | 0.081 (5) | 0.045 (4) | −0.011 (4) | 0.007 (3) | 0.010 (4) |
C3 | 0.067 (6) | 0.078 (6) | 0.032 (4) | 0.004 (3) | 0.018 (4) | 0.001 (3) |
C4 | 0.072 (5) | 0.064 (4) | 0.044 (4) | 0.007 (4) | −0.006 (3) | −0.017 (4) |
C5 | 0.052 (4) | 0.054 (4) | 0.043 (3) | −0.002 (3) | 0.002 (3) | 0.005 (3) |
C6 | 0.032 (3) | 0.058 (4) | 0.044 (3) | 0.015 (3) | −0.013 (3) | 0.002 (3) |
C7 | 0.054 (4) | 0.035 (3) | 0.048 (3) | −0.001 (2) | −0.012 (3) | 0.006 (3) |
C8 | 0.096 (5) | 0.049 (4) | 0.061 (4) | 0.002 (3) | 0.011 (4) | 0.001 (3) |
C9 | 0.116 (6) | 0.038 (3) | 0.073 (5) | −0.003 (3) | 0.023 (5) | 0.005 (3) |
C10 | 0.125 (7) | 0.041 (4) | 0.068 (4) | −0.001 (4) | 0.009 (4) | 0.005 (3) |
C11 | 0.078 (5) | 0.042 (3) | 0.046 (4) | 0.001 (3) | 0.002 (3) | −0.003 (3) |
O1—C20 | 1.363 (8) | O3—C1 | 1.374 (8) |
O1—C12 | 1.386 (8) | O3—C9 | 1.411 (8) |
O2—C22 | 1.228 (7) | O4—C11 | 1.235 (7) |
N1—C18 | 1.278 (8) | N3—C7 | 1.308 (8) |
N1—N2 | 1.373 (9) | N3—N4 | 1.418 (8) |
N2—C22 | 1.353 (8) | N4—C11 | 1.330 (7) |
N2—H2A | 0.8611 | N4—H4A | 0.8591 |
C12—C13 | 1.373 (10) | C1—C2 | 1.385 (10) |
C12—C17 | 1.425 (9) | C1—C6 | 1.386 (10) |
C13—C14 | 1.403 (13) | C2—C3 | 1.350 (11) |
C13—H13 | 0.9300 | C2—H2 | 0.9300 |
C14—C15 | 1.402 (12) | C3—C4 | 1.365 (10) |
C14—H14 | 0.9300 | C3—H3 | 0.9300 |
C15—C16 | 1.355 (11) | C4—C5 | 1.403 (10) |
C15—H15 | 0.9300 | C4—H4 | 0.9300 |
C16—C17 | 1.401 (9) | C5—C6 | 1.371 (9) |
C16—H16 | 0.9300 | C5—H5 | 0.9300 |
C17—C18 | 1.447 (9) | C6—C7 | 1.470 (9) |
C18—C19 | 1.490 (9) | C7—C8 | 1.506 (9) |
C19—C21 | 1.460 (9) | C8—C9 | 1.458 (9) |
C19—C20 | 1.475 (9) | C8—C10 | 1.480 (10) |
C19—H19 | 0.9800 | C8—H8 | 0.9800 |
C20—H20A | 0.9700 | C9—H9A | 0.9700 |
C20—H20B | 0.9700 | C9—H9B | 0.9700 |
C21—C22 | 1.495 (8) | C10—C11 | 1.487 (8) |
C21—H21A | 0.9700 | C10—H10A | 0.9700 |
C21—H21B | 0.9700 | C10—H10B | 0.9700 |
C20—O1—C12 | 117.3 (5) | C1—O3—C9 | 114.7 (5) |
C18—N1—N2 | 117.5 (6) | C7—N3—N4 | 115.5 (5) |
C22—N2—N1 | 127.3 (6) | C11—N4—N3 | 127.1 (5) |
C22—N2—H2A | 116.1 | C11—N4—H4A | 116.7 |
N1—N2—H2A | 116.6 | N3—N4—H4A | 116.2 |
C13—C12—O1 | 116.2 (6) | O3—C1—C2 | 116.5 (6) |
C13—C12—C17 | 123.9 (8) | O3—C1—C6 | 123.7 (6) |
O1—C12—C17 | 119.9 (6) | C2—C1—C6 | 119.8 (7) |
C12—C13—C14 | 117.5 (8) | C3—C2—C1 | 120.9 (7) |
C12—C13—H13 | 121.3 | C3—C2—H2 | 119.6 |
C14—C13—H13 | 121.3 | C1—C2—H2 | 119.6 |
C15—C14—C13 | 120.8 (9) | C2—C3—C4 | 120.8 (7) |
C15—C14—H14 | 119.6 | C2—C3—H3 | 119.6 |
C13—C14—H14 | 119.6 | C4—C3—H3 | 119.6 |
C16—C15—C14 | 119.4 (9) | C3—C4—C5 | 118.6 (7) |
C16—C15—H15 | 120.3 | C3—C4—H4 | 120.7 |
C14—C15—H15 | 120.3 | C5—C4—H4 | 120.7 |
C15—C16—C17 | 123.4 (7) | C6—C5—C4 | 121.2 (6) |
C15—C16—H16 | 118.3 | C6—C5—H5 | 119.4 |
C17—C16—H16 | 118.3 | C4—C5—H5 | 119.4 |
C16—C17—C12 | 115.0 (6) | C5—C6—C1 | 118.6 (6) |
C16—C17—C18 | 124.6 (7) | C5—C6—C7 | 122.6 (7) |
C12—C17—C18 | 120.3 (7) | C1—C6—C7 | 118.5 (6) |
N1—C18—C17 | 120.1 (7) | N3—C7—C6 | 118.8 (6) |
N1—C18—C19 | 122.4 (6) | N3—C7—C8 | 123.6 (6) |
C17—C18—C19 | 117.3 (6) | C6—C7—C8 | 117.6 (5) |
C21—C19—C20 | 116.4 (6) | C9—C8—C10 | 116.1 (6) |
C21—C19—C18 | 112.5 (5) | C9—C8—C7 | 111.6 (5) |
C20—C19—C18 | 111.9 (6) | C10—C8—C7 | 111.5 (6) |
C21—C19—H19 | 104.9 | C9—C8—H8 | 105.6 |
C20—C19—H19 | 104.9 | C10—C8—H8 | 105.6 |
C18—C19—H19 | 104.9 | C7—C8—H8 | 105.6 |
O1—C20—C19 | 117.7 (6) | O3—C9—C8 | 117.2 (6) |
O1—C20—H20A | 107.9 | O3—C9—H9A | 108.0 |
C19—C20—H20A | 107.9 | C8—C9—H9A | 108.0 |
O1—C20—H20B | 107.9 | O3—C9—H9B | 108.0 |
C19—C20—H20B | 107.9 | C8—C9—H9B | 108.0 |
H20A—C20—H20B | 107.2 | H9A—C9—H9B | 107.2 |
C19—C21—C22 | 114.3 (6) | C8—C10—C11 | 114.3 (6) |
C19—C21—H21A | 108.7 | C8—C10—H10A | 108.7 |
C22—C21—H21A | 108.7 | C11—C10—H10A | 108.7 |
C19—C21—H21B | 108.7 | C8—C10—H10B | 108.7 |
C22—C21—H21B | 108.7 | C11—C10—H10B | 108.7 |
H21A—C21—H21B | 107.6 | H10A—C10—H10B | 107.6 |
O2—C22—N2 | 122.0 (6) | O4—C11—N4 | 120.4 (5) |
O2—C22—C21 | 123.9 (6) | O4—C11—C10 | 123.1 (6) |
N2—C22—C21 | 114.0 (6) | N4—C11—C10 | 116.4 (6) |
C18—N1—N2—C22 | 15.7 (12) | C7—N3—N4—C11 | 13.0 (12) |
C20—O1—C12—C13 | 158.2 (7) | C9—O3—C1—C2 | 160.0 (7) |
C20—O1—C12—C17 | −21.0 (10) | C9—O3—C1—C6 | −20.1 (10) |
O1—C12—C13—C14 | 179.3 (7) | O3—C1—C2—C3 | 178.2 (8) |
C17—C12—C13—C14 | −1.6 (12) | C6—C1—C2—C3 | −1.7 (12) |
C12—C13—C14—C15 | 3.0 (13) | C1—C2—C3—C4 | −1.7 (15) |
C13—C14—C15—C16 | −1.2 (14) | C2—C3—C4—C5 | 3.2 (14) |
C14—C15—C16—C17 | −2.2 (12) | C3—C4—C5—C6 | −1.3 (11) |
C15—C16—C17—C12 | 3.4 (11) | C4—C5—C6—C1 | −2.0 (10) |
C15—C16—C17—C18 | −179.4 (7) | C4—C5—C6—C7 | −174.9 (6) |
C13—C12—C17—C16 | −1.5 (11) | O3—C1—C6—C5 | −176.4 (6) |
O1—C12—C17—C16 | 177.6 (6) | C2—C1—C6—C5 | 3.5 (10) |
C13—C12—C17—C18 | −178.8 (7) | O3—C1—C6—C7 | −3.2 (10) |
O1—C12—C17—C18 | 0.3 (10) | C2—C1—C6—C7 | 176.7 (6) |
N2—N1—C18—C17 | 176.5 (6) | N4—N3—C7—C6 | −178.2 (6) |
N2—N1—C18—C19 | 0.8 (10) | N4—N3—C7—C8 | 2.8 (10) |
C16—C17—C18—N1 | 4.3 (10) | C5—C6—C7—N3 | −4.2 (9) |
C12—C17—C18—N1 | −178.6 (6) | C1—C6—C7—N3 | −177.1 (6) |
C16—C17—C18—C19 | −179.8 (7) | C5—C6—C7—C8 | 174.8 (6) |
C12—C17—C18—C19 | −2.8 (10) | C1—C6—C7—C8 | 1.9 (9) |
N1—C18—C19—C21 | −27.9 (10) | N3—C7—C8—C9 | −159.9 (7) |
C17—C18—C19—C21 | 156.3 (7) | C6—C7—C8—C9 | 21.1 (9) |
N1—C18—C19—C20 | −161.1 (7) | N3—C7—C8—C10 | −28.3 (10) |
C17—C18—C19—C20 | 23.1 (9) | C6—C7—C8—C10 | 152.8 (6) |
C12—O1—C20—C19 | 44.5 (9) | C1—O3—C9—C8 | 45.9 (9) |
C21—C19—C20—O1 | −176.1 (6) | C10—C8—C9—O3 | −175.0 (7) |
C18—C19—C20—O1 | −44.8 (10) | C7—C8—C9—O3 | −45.7 (10) |
C20—C19—C21—C22 | 170.1 (6) | C9—C8—C10—C11 | 168.0 (7) |
C18—C19—C21—C22 | 39.1 (10) | C7—C8—C10—C11 | 38.7 (9) |
N1—N2—C22—O2 | 175.1 (7) | N3—N4—C11—O4 | 177.3 (7) |
N1—N2—C22—C21 | −2.1 (12) | N3—N4—C11—C10 | −0.1 (12) |
C19—C21—C22—O2 | 156.8 (7) | C8—C10—C11—O4 | 155.8 (7) |
C19—C21—C22—N2 | −26.0 (10) | C8—C10—C11—N4 | −26.9 (10) |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2A···O4 | 0.86 | 2.11 | 2.902 (7) | 154 |
N4—H4A···O2i | 0.86 | 2.07 | 2.891 (7) | 159 |
C21—H21B···O4ii | 0.97 | 2.44 | 3.312 (8) | 149 |
Symmetry codes: (i) x, y−1, z; (ii) x, y+1, z. |
Experimental details
Crystal data | |
Chemical formula | C11H10N2O2 |
Mr | 202.21 |
Crystal system, space group | Orthorhombic, Pca21 |
Temperature (K) | 292 |
a, b, c (Å) | 7.6838 (10), 7.4659 (9), 33.322 (4) |
V (Å3) | 1911.6 (4) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.40 × 0.30 × 0.10 |
Data collection | |
Diffractometer | Bruker SMART 4K CCD area-detector |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.961, 0.990 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 9576, 1906, 1211 |
Rint | 0.057 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.057, 0.179, 1.00 |
No. of reflections | 1906 |
No. of parameters | 271 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.19, −0.18 |
Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003), SHELXTL (Bruker, 2001).
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2A···O4 | 0.86 | 2.11 | 2.902 (7) | 154 |
N4—H4A···O2i | 0.86 | 2.07 | 2.891 (7) | 159 |
C21—H21B···O4ii | 0.97 | 2.44 | 3.312 (8) | 149 |
Symmetry codes: (i) x, y−1, z; (ii) x, y+1, z. |
Flavonoids, occurring widely throughout the plant kingdom, are one of the most representative families of plant secondary metabolites and display a remarkable
spectrum of biological activities. They are used as a synthetic lead for drug discovery (Ren et al., 2003). The title compound, (I) (Fig. 1), is an important intermediate for the synthesis of flavonoid derivatives.
Compound (I) contains two independent molecules (A and B) in the asymmetric unit, with bond lengths and angles within normal ranges (Allen et al., 1987). The six-membered pyran ring adopts a half-chair conformation in molecule A (atoms C1/C6–C9/O3) and an envelope conformation in molecule B (atoms C12/C17–C20/O1). The fused heterocyclic ring (atoms C7/C8/C10/C11/N4/N3 in A; atoms C18/C19/C21/C22/N1/N2 in B) adopts a sofa conformation in both molecules.
The structure is stabilized by weak N—H···O hydrogen-bonding interactions (Table 1). The hydrogen bonds link pairs of independent molecules into dimers, while the N—H···O interactions link pairs of dimers into chains in the bc plane. A short C—H···O contact is also present. Further stability is provided
by offset π–π stacking interactions between adjacent C1–C6 and C12–C17 benzene rings. The centroid–centroid distance is 3.860 (5) Å.