organic compounds
2,4-Dinitro-1-naphthol
aDepartment of Chemistry, University of Sargodha, Sargodha, Pakistan, and bDepartment of Physics, University of Sargodha, Sargodha, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com
In the title compound, C10H6N2O5, the two fused rings are almost co-planar, with an r.m.s. deviation of 0.0163 Å. The nitro groups are oriented at dihedral angles of 2.62 (11) and 44.69 (11)° with respect to the plane of the parent fused rings. Intramolecular O—H⋯O and C—H⋯O hydrogen bonds complete S(6) ring motifs. In the crystal, molecules are linked into chains along [101] by intermolecular O—H⋯O hydrogen bonds. π–π interactions [centroid–centroid distances = 3.6296 (15), 3.8104 (15) and 3.6513 (14) Å] might play a role in stabilizing the structure.
Related literature
For background to estrogens, see: Schwartz et al. (1995); O'Donnell et al. (2001). For related structures, see: Filipenko et al. (2001); Rozycka-Sokolowska et al. (2004). For graph-set notation, see: Bernstein et al. (1995). For π–π interactions, see: Janiak (2000).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); 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, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON.
Supporting information
https://doi.org/10.1107/S1600536810045034/dn2615sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810045034/dn2615Isup2.hkl
The 1-tetralone (1 ml, 1.1 g, 1 eq) was added to a chilled and well stirred nitrating mixture containing H2SO4 (2 ml, 0.57 g, 2 eq) and HNO3 (0.5 ml, 0.7 g, 1.5 eq). The reaction mixture was then neutralized and extracted with EtOAc (3 × 25 ml) and the combined organic extract was dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product was purified by
and the title compound (I) was obtained as dull brown crystalline solid in 61–79th fraction (20 ml each) using 2.5% CHCl3 (3 × 500 ml) as mobile phase. Yield: 15%.The H-atoms were positioned geometrically with (O–H = 0.82, C–H = 0.93 Å) and treated as riding with Uiso(H) = 1.2Ueq(C, O).
Estrogens have been found to have maintenance effects on bone, brain, skin, cardiovascular system (Schwartz et al., 1995). In spite of their beneficial biological effects, estrogens are suspected to have relationship with the risk of cancer and thromboemetic diseases (O'Donnell et al., 2001). The title compound was obtained as an interesting side product while synthesizing substituted 1-tetralone as AB ring of the estrogen skeleton which will bear substituent at positions not found in nature.
The title compound (I) is related to the published crystal structures of 1-naphthalenol (Rozycka-Sokolowska et al., 2004) and hydroxonium 2,4-dinitro-1-hydroxy-7-sulfonatonaphthalene monohydrate (Filipenko et al., 2001).
In (I), the two fused rings (C1—C10) are neraly planar with the largest deviation being 0.033 (2)Å at C10 (Fig. 1). The hydroxyl O5 atom is only deviating by 0.129 (2)Å from the mean plane. Owing to the intramolecular O5–H···O4 hydrogen bond (Table 1), the O3 and O4 atoms are only slightly displaced from the mean plane of the fused rings by -0.074 (2)Å and 0.023 (2) Å, respectively. The other nitro group is twisted by 44.72 (12)° with respect to the fused rings.
Strong intramolecular H-bondings of O—H···O and C—H···O types (Table 1, Fig. 1) complete S(6) ring motifs (Bernstein et al., 1995). The molecules are stabilized in the form of polymeric chains due to intermolecular O—H···O hydrogen bonds (Table 1, Fig. 2). Slippest weak π–π interactions (Table 2) might play a role in stabilizing the packing.
For background to estrogens, see: Schwartz et al. (1995); O'Donnell et al. (2001). For related structures, see: Filipenko et al. (2001); Rozycka-Sokolowska et al. (2004). For graph-set notation, see: Bernstein et al. (1995). For π–π interactions, see: Janiak (2000).
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).C10H6N2O5 | F(000) = 480 |
Mr = 234.17 | Dx = 1.647 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 1058 reflections |
a = 7.0512 (10) Å | θ = 2.5–25.1° |
b = 16.3541 (19) Å | µ = 0.14 mm−1 |
c = 8.7988 (10) Å | T = 296 K |
β = 111.452 (6)° | Needle, brown |
V = 944.4 (2) Å3 | 0.32 × 0.14 × 0.12 mm |
Z = 4 |
Bruker Kappa APEXII CCD diffractometer | 1684 independent reflections |
Radiation source: fine-focus sealed tube | 1058 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.052 |
Detector resolution: 8.20 pixels mm-1 | θmax = 25.1°, θmin = 2.5° |
ω scans | h = −7→8 |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | k = −19→19 |
Tmin = 0.978, Tmax = 0.982 | l = −10→10 |
6868 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)] = 0.042 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.119 | H-atom parameters constrained |
S = 1.00 | w = 1/[σ2(Fo2) + (0.059P)2] where P = (Fo2 + 2Fc2)/3 |
1684 reflections | (Δ/σ)max < 0.001 |
155 parameters | Δρmax = 0.18 e Å−3 |
0 restraints | Δρmin = −0.17 e Å−3 |
C10H6N2O5 | V = 944.4 (2) Å3 |
Mr = 234.17 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 7.0512 (10) Å | µ = 0.14 mm−1 |
b = 16.3541 (19) Å | T = 296 K |
c = 8.7988 (10) Å | 0.32 × 0.14 × 0.12 mm |
β = 111.452 (6)° |
Bruker Kappa APEXII CCD diffractometer | 1684 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | 1058 reflections with I > 2σ(I) |
Tmin = 0.978, Tmax = 0.982 | Rint = 0.052 |
6868 measured reflections |
R[F2 > 2σ(F2)] = 0.042 | 0 restraints |
wR(F2) = 0.119 | H-atom parameters constrained |
S = 1.00 | Δρmax = 0.18 e Å−3 |
1684 reflections | Δρmin = −0.17 e Å−3 |
155 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 | 0.3884 (3) | 0.45828 (13) | 0.10925 (19) | 0.0656 (6) | |
O2 | 0.6120 (3) | 0.36519 (11) | 0.1294 (2) | 0.0663 (6) | |
O3 | 0.8511 (3) | 0.26242 (11) | 0.6881 (2) | 0.0762 (7) | |
O4 | 1.0038 (3) | 0.34485 (11) | 0.8845 (2) | 0.0735 (6) | |
O5 | 0.9984 (3) | 0.49989 (10) | 0.83341 (16) | 0.0500 (5) | |
H5A | 1.0356 | 0.4587 | 0.8896 | 0.060* | |
N1 | 0.5444 (3) | 0.42063 (12) | 0.1860 (2) | 0.0441 (5) | |
N2 | 0.8995 (3) | 0.33110 (13) | 0.7401 (3) | 0.0497 (6) | |
C1 | 0.8052 (3) | 0.54453 (12) | 0.5693 (2) | 0.0313 (5) | |
C2 | 0.8467 (4) | 0.62585 (14) | 0.6216 (3) | 0.0415 (6) | |
H2 | 0.9197 | 0.6370 | 0.7312 | 0.050* | |
C3 | 0.7809 (4) | 0.68880 (14) | 0.5131 (3) | 0.0465 (7) | |
H3 | 0.8077 | 0.7426 | 0.5489 | 0.056* | |
C4 | 0.6744 (4) | 0.67246 (15) | 0.3500 (3) | 0.0487 (7) | |
H4 | 0.6329 | 0.7157 | 0.2766 | 0.058* | |
C5 | 0.6283 (4) | 0.59409 (15) | 0.2936 (3) | 0.0419 (6) | |
H5 | 0.5557 | 0.5848 | 0.1832 | 0.050* | |
C6 | 0.6905 (3) | 0.52753 (13) | 0.4024 (2) | 0.0313 (5) | |
C7 | 0.6553 (3) | 0.44389 (13) | 0.3569 (2) | 0.0334 (5) | |
C8 | 0.7224 (3) | 0.38182 (13) | 0.4646 (2) | 0.0373 (6) | |
H8 | 0.6948 | 0.3279 | 0.4299 | 0.045* | |
C9 | 0.8335 (3) | 0.39941 (13) | 0.6284 (2) | 0.0354 (6) | |
C10 | 0.8816 (3) | 0.47868 (13) | 0.6824 (2) | 0.0345 (5) |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0468 (12) | 0.0892 (14) | 0.0412 (10) | 0.0043 (11) | −0.0071 (9) | −0.0067 (9) |
O2 | 0.0875 (16) | 0.0570 (12) | 0.0489 (11) | 0.0026 (11) | 0.0184 (10) | −0.0192 (9) |
O3 | 0.110 (2) | 0.0391 (11) | 0.0731 (13) | −0.0007 (11) | 0.0256 (12) | 0.0117 (9) |
O4 | 0.0881 (16) | 0.0695 (13) | 0.0441 (11) | −0.0059 (11) | 0.0017 (11) | 0.0225 (9) |
O5 | 0.0560 (12) | 0.0565 (10) | 0.0260 (9) | −0.0001 (9) | 0.0012 (8) | 0.0046 (7) |
N1 | 0.0459 (14) | 0.0488 (12) | 0.0320 (11) | −0.0085 (11) | 0.0075 (10) | −0.0052 (9) |
N2 | 0.0521 (15) | 0.0483 (14) | 0.0490 (13) | 0.0019 (11) | 0.0190 (11) | 0.0158 (10) |
C1 | 0.0258 (13) | 0.0386 (12) | 0.0291 (11) | 0.0020 (10) | 0.0096 (9) | −0.0002 (9) |
C2 | 0.0405 (15) | 0.0446 (14) | 0.0385 (13) | −0.0023 (11) | 0.0132 (11) | −0.0055 (11) |
C3 | 0.0493 (17) | 0.0376 (14) | 0.0519 (15) | 0.0043 (12) | 0.0175 (13) | 0.0013 (11) |
C4 | 0.0490 (17) | 0.0448 (15) | 0.0489 (15) | 0.0094 (12) | 0.0139 (13) | 0.0142 (12) |
C5 | 0.0368 (15) | 0.0526 (15) | 0.0317 (12) | 0.0054 (12) | 0.0070 (10) | 0.0065 (11) |
C6 | 0.0235 (12) | 0.0401 (12) | 0.0298 (11) | 0.0026 (10) | 0.0093 (9) | 0.0016 (9) |
C7 | 0.0267 (13) | 0.0435 (13) | 0.0272 (11) | −0.0026 (10) | 0.0066 (9) | −0.0030 (10) |
C8 | 0.0347 (14) | 0.0384 (13) | 0.0388 (13) | −0.0021 (11) | 0.0137 (11) | −0.0017 (10) |
C9 | 0.0337 (14) | 0.0404 (13) | 0.0321 (12) | 0.0021 (10) | 0.0120 (10) | 0.0083 (10) |
C10 | 0.0307 (13) | 0.0474 (14) | 0.0247 (11) | 0.0008 (11) | 0.0093 (10) | 0.0021 (10) |
O1—N1 | 1.225 (2) | C2—H2 | 0.9300 |
O2—N1 | 1.213 (2) | C3—C4 | 1.381 (3) |
O3—N2 | 1.214 (3) | C3—H3 | 0.9300 |
O4—N2 | 1.234 (3) | C4—C5 | 1.370 (3) |
O5—C10 | 1.328 (2) | C4—H4 | 0.9300 |
O5—H5A | 0.8200 | C5—C6 | 1.409 (3) |
N1—C7 | 1.469 (3) | C5—H5 | 0.9300 |
N2—C9 | 1.448 (3) | C6—C7 | 1.421 (3) |
C1—C2 | 1.403 (3) | C7—C8 | 1.351 (3) |
C1—C6 | 1.421 (3) | C8—C9 | 1.395 (3) |
C1—C10 | 1.431 (3) | C8—H8 | 0.9300 |
C2—C3 | 1.365 (3) | C9—C10 | 1.380 (3) |
C10—O5—H5A | 109.5 | C4—C5—C6 | 120.2 (2) |
O2—N1—O1 | 123.9 (2) | C4—C5—H5 | 119.9 |
O2—N1—C7 | 118.2 (2) | C6—C5—H5 | 119.9 |
O1—N1—C7 | 117.9 (2) | C5—C6—C7 | 124.98 (19) |
O3—N2—O4 | 122.4 (2) | C5—C6—C1 | 118.0 (2) |
O3—N2—C9 | 118.8 (2) | C7—C6—C1 | 117.00 (19) |
O4—N2—C9 | 118.8 (2) | C8—C7—C6 | 123.06 (19) |
C2—C1—C6 | 119.75 (19) | C8—C7—N1 | 116.25 (19) |
C2—C1—C10 | 120.33 (19) | C6—C7—N1 | 120.68 (18) |
C6—C1—C10 | 119.90 (19) | C7—C8—C9 | 119.3 (2) |
C3—C2—C1 | 120.6 (2) | C7—C8—H8 | 120.3 |
C3—C2—H2 | 119.7 | C9—C8—H8 | 120.3 |
C1—C2—H2 | 119.7 | C10—C9—C8 | 121.60 (19) |
C2—C3—C4 | 119.8 (2) | C10—C9—N2 | 120.89 (19) |
C2—C3—H3 | 120.1 | C8—C9—N2 | 117.5 (2) |
C4—C3—H3 | 120.1 | O5—C10—C9 | 125.07 (19) |
C5—C4—C3 | 121.6 (2) | O5—C10—C1 | 115.92 (19) |
C5—C4—H4 | 119.2 | C9—C10—C1 | 119.00 (18) |
C3—C4—H4 | 119.2 | ||
C6—C1—C2—C3 | −1.1 (3) | O1—N1—C7—C6 | −44.9 (3) |
C10—C1—C2—C3 | 177.5 (2) | C6—C7—C8—C9 | −0.7 (3) |
C1—C2—C3—C4 | −0.7 (4) | N1—C7—C8—C9 | 178.4 (2) |
C2—C3—C4—C5 | 1.5 (4) | C7—C8—C9—C10 | −1.9 (3) |
C3—C4—C5—C6 | −0.4 (4) | C7—C8—C9—N2 | 179.0 (2) |
C4—C5—C6—C7 | −178.5 (2) | O3—N2—C9—C10 | 178.8 (2) |
C4—C5—C6—C1 | −1.4 (3) | O4—N2—C9—C10 | −1.5 (3) |
C2—C1—C6—C5 | 2.1 (3) | O3—N2—C9—C8 | −2.1 (3) |
C10—C1—C6—C5 | −176.42 (19) | O4—N2—C9—C8 | 177.6 (2) |
C2—C1—C6—C7 | 179.44 (19) | C8—C9—C10—O5 | −175.0 (2) |
C10—C1—C6—C7 | 0.9 (3) | N2—C9—C10—O5 | 4.1 (3) |
C5—C6—C7—C8 | 178.2 (2) | C8—C9—C10—C1 | 3.8 (3) |
C1—C6—C7—C8 | 1.1 (3) | N2—C9—C10—C1 | −177.11 (19) |
C5—C6—C7—N1 | −0.8 (3) | C2—C1—C10—O5 | −2.9 (3) |
C1—C6—C7—N1 | −177.9 (2) | C6—C1—C10—O5 | 175.7 (2) |
O2—N1—C7—C8 | −43.7 (3) | C2—C1—C10—C9 | 178.2 (2) |
O1—N1—C7—C8 | 136.1 (2) | C6—C1—C10—C9 | −3.2 (3) |
O2—N1—C7—C6 | 135.4 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
O5—H5A···O1i | 0.82 | 2.53 | 3.006 (3) | 118 |
O5—H5A···O4 | 0.82 | 1.87 | 2.573 (2) | 142 |
O5—H5A···N2 | 0.82 | 2.47 | 2.892 (3) | 113 |
C5—H5···O1 | 0.93 | 2.35 | 2.902 (3) | 118 |
Symmetry code: (i) x+1, y, z+1. |
Experimental details
Crystal data | |
Chemical formula | C10H6N2O5 |
Mr | 234.17 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 296 |
a, b, c (Å) | 7.0512 (10), 16.3541 (19), 8.7988 (10) |
β (°) | 111.452 (6) |
V (Å3) | 944.4 (2) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.14 |
Crystal size (mm) | 0.32 × 0.14 × 0.12 |
Data collection | |
Diffractometer | Bruker Kappa APEXII CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2005) |
Tmin, Tmax | 0.978, 0.982 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6868, 1684, 1058 |
Rint | 0.052 |
(sin θ/λ)max (Å−1) | 0.597 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.042, 0.119, 1.00 |
No. of reflections | 1684 |
No. of parameters | 155 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.18, −0.17 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
O5—H5A···O1i | 0.82 | 2.53 | 3.006 (3) | 118 |
O5—H5A···O4 | 0.82 | 1.87 | 2.573 (2) | 142 |
O5—H5A···N2 | 0.82 | 2.47 | 2.892 (3) | 113 |
C5—H5···O1 | 0.93 | 2.35 | 2.902 (3) | 118 |
Symmetry code: (i) x+1, y, z+1. |
Cg1 and Cg2 are the centroids of the C1–C6 and C1/C6–C10 rings, respectively. ipd is the mean interplanar distance (distance from one plane to the neighbouring centroid) and sa is the slippage angle (angle subtended by the intercentroid vector to the plane normal). For details, see Janiak (2000) |
Cg···Cg | ipd | sa | |
Cg1···Cg2i | 3.6296 (15) | 3.365 | 1.305 |
Cg1···Cg2ii | 3.8104 (15) | 3.552 | 1.323 |
Cg2···Cg2i | 3.6513 (14) | 3.378 | 1.386 |
Symmetry codes: (i) 1-x, 1-y, 1-z, (ii) 2-x, 1-y, 1-z. |
Acknowledgements
The authors acknowledge the provision of funds for the purchase of the diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha, Pakistan. ARR also acknowledges the Higher Education Commission, Government of Pakistan, for generous support of the research project (20–819).
References
Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573. CrossRef CAS Web of Science Google Scholar
Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838. CrossRef CAS IUCr Journals Google Scholar
Filipenko, O. S., Chuev, I. I., Leonova, L. S., Shilov, G. V. & Aldoshin, S. M. (2001). Dokl. Phys. Chem. 376, 27–30. Web of Science CrossRef Google Scholar
Janiak, C. (2000). J. Chem. Soc. Dalton Trans. pp. 3885–3896. Web of Science CrossRef Google Scholar
O'Donnell, L., Kristen, M. R., Margaret, E. J. & Evan, R. S. (2001). Endocr. Rev. 22, 289–318. Web of Science CrossRef PubMed CAS Google Scholar
Rozycka-Sokolowska, E., Marciniak, B. & Pavlyuk, V. (2004). Acta Cryst. E60, o884–o885. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Schwartz, J., Freeman, R. & Frishman, W. (1995). J. Clin. Pharmacol. 35, 1–16. CrossRef CAS PubMed Web of Science Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
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Estrogens have been found to have maintenance effects on bone, brain, skin, cardiovascular system (Schwartz et al., 1995). In spite of their beneficial biological effects, estrogens are suspected to have relationship with the risk of cancer and thromboemetic diseases (O'Donnell et al., 2001). The title compound was obtained as an interesting side product while synthesizing substituted 1-tetralone as AB ring of the estrogen skeleton which will bear substituent at positions not found in nature.
The title compound (I) is related to the published crystal structures of 1-naphthalenol (Rozycka-Sokolowska et al., 2004) and hydroxonium 2,4-dinitro-1-hydroxy-7-sulfonatonaphthalene monohydrate (Filipenko et al., 2001).
In (I), the two fused rings (C1—C10) are neraly planar with the largest deviation being 0.033 (2)Å at C10 (Fig. 1). The hydroxyl O5 atom is only deviating by 0.129 (2)Å from the mean plane. Owing to the intramolecular O5–H···O4 hydrogen bond (Table 1), the O3 and O4 atoms are only slightly displaced from the mean plane of the fused rings by -0.074 (2)Å and 0.023 (2) Å, respectively. The other nitro group is twisted by 44.72 (12)° with respect to the fused rings.
Strong intramolecular H-bondings of O—H···O and C—H···O types (Table 1, Fig. 1) complete S(6) ring motifs (Bernstein et al., 1995). The molecules are stabilized in the form of polymeric chains due to intermolecular O—H···O hydrogen bonds (Table 1, Fig. 2). Slippest weak π–π interactions (Table 2) might play a role in stabilizing the packing.