2-Hydr­oxy-3-nitro­benzamide

Raza, A.R.; Danish, M.; Tahir, M.N.; Nisar, B.; Iqbal, M.S.

doi:10.1107/S1600536809022843

organic compounds

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ISSN: 2056-9890

Volume 65| Part 7| July 2009| Page o1630

doi:10.1107/S1600536809022843

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2-Hydroxy-3-nitrobenzamide

Abdul Rauf Raza,^a Muhammad Danish,^a M. Nawaz Tahir,^b ^* Bushra Nisar ^a and Mohammad S. Iqbal ^c

^aDepartment of Chemistry, University of Sargodha, Sargodha, Pakistan, ^bDepartment of Physics, University of Sargodha, Sargodha, Pakistan, and ^cDepartment of Chemistry, Government College University, Lahore, Pakistan
^*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 13 June 2009; accepted 14 June 2009; online 20 June 2009)

The asymmetric unit of title compound, C₇H₆N₂O₄, contains two molecules, one of which has a disordered nitro group with an occupancy ratio of 0.517 (9):0.483 (9) for the O atoms. Both molecules contain an intramolecular O—H⋯O hydrogen bond. In the crystal, both molecules form inversion dimers linked by pairs of N—H⋯O hydrogen bonds, resulting in R₂²(8) ring motifs. The dimers are connected by further N—H⋯O links and weak C—H⋯O interactions, resulting in a layered motif.

Related literature

For related structures, see: Liu & Zhu (2007 ); Pertlik (1990 ). For graph-set notation, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₇H₆N₂O₄
M_r = 182.14
Triclinic, $[P \overline 1]$
a = 3.8390 (2) Å
b = 13.0347 (8) Å
c = 16.0409 (9) Å
α = 98.207 (3)°
β = 95.658 (2)°
γ = 98.365 (3)°
V = 780.16 (8) Å³
Z = 4
Mo Kα radiation
μ = 0.13 mm⁻¹
T = 296 K
0.25 × 0.22 × 0.18 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.966, T_max = 0.979
15183 measured reflections
3658 independent reflections
1932 reflections with I > 2σ(I)
R_int = 0.039

Refinement

R[F² > 2σ(F²)] = 0.048
wR(F²) = 0.139
S = 1.00
3658 reflections
287 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.18 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1O⋯O4	0.82	1.77	2.500 (2)	148
N2—H2A⋯O6Aⁱ	0.80 (3)	2.38 (3)	3.142 (5)	161 (3)
N2—H2B⋯O4ⁱⁱ	0.93 (3)	2.03 (3)	2.966 (3)	177 (2)
N4—H4A⋯O8ⁱⁱⁱ	0.87 (3)	2.07 (3)	2.929 (3)	172 (2)
N4—H4B⋯O2^iv	0.91 (3)	2.18 (3)	3.084 (3)	174 (2)
O5—H5O⋯O8	0.82	1.76	2.496 (2)	148
C6—H6⋯O6Aⁱ	0.91 (2)	2.40 (2)	3.285 (6)	163 (2)
C11—H11⋯O7A^v	0.92 (2)	2.41 (2)	3.221 (6)	147 (2)
C11—H11⋯O7A^vi	0.92 (2)	2.55 (2)	2.997 (6)	110.5 (17)
C13—H13⋯O2^iv	0.92 (2)	2.39 (2)	3.289 (3)	165 (2)
Symmetry codes: (i) x-1, y, z; (ii) -x+1, -y+1, -z; (iii) -x+3, -y, -z+1; (iv) x-1, y-1, z; (v) -x+1, -y, -z; (vi) -x+2, -y, -z.

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); 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 (Farrugia, 1997 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ) and PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809022843/hb5009sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809022843/hb5009Isup2.hkl

checkCIF report

Comment top

The title compound (I), (Fig. 1), has been prepared as an intermediate for derivatization. The purpose of structure determination was to investigate the amount and position of nitration on the 2-hydroxybenzamide.

The crystal structures of (II) 2-Hydroxybenzamide (Pertlik, 1990) and (III) 2-Hydroxy-3,5-dinitrobenzamide monohydrate (Liu & Zhu, 2007) have been published which contain the common group of hydroxybenzamide as in (I).

The title compound consists of two molecules in the asymmetric unit. The O-atoms of nitro group in one of the molecules are disordered over two sites with occupancy ratio of 0.517 (9):0.483 (9). In both molecules the hydroxy group form intramolecular H-bonding with the O-atom of amide group, thus completing ring motifs R₁¹(6) (Bernstein et al., 1995). The H-atoms of NH₂ groups behave differently. One H-atom forms dimer, whereas the other is used in linkage of the dimers. It is intersting that both molecules form dimers among themselves through the intermolecular H-bonds of N—H···O type with ring motifs R₂²(8). The dimers of both molecules are connected to each other through the same type of intermolecular H-bonding (Fig. 2). The molecules are stabilized in the form of two dimensional polymeric sheets due to intera as well as intermolecular H-bonding (Table 1).

Related literature top

For related structures, see: Liu & Zhu (2007); Pertlik (1990). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

A solution of 2-hydroxybenzamide (1.37 g, 0.01 mol) in ethylacetate (EtOAc) (25 ml) was added dropwise to a nitrating mixture of HNO₃ (1.89 g, 0.03 mol) and H₂SO₄ (1.96 g, 0.02 mol) with constant stirring while the temperature was kept below 278 K. Then reaction mixture was stirred at room temperature for 4–5 h. The resulting mixture was refluxed for 1 h, cooled, neutralized with aq. NaHCO₃ (10%) and extracted with EtOAc (3 × 25 ml). The organic layers were combined, dried over anhydrous Na₂SO₄, filtered and concentrated under reduced pressure to afford a reddish brown solid. The column chromatographic purification with 0, 2.5, 5 and 7.5% EtOAc in petrol (0.5 L each) over a silica gel packed column (25.5 cm) afforded brown prisms of (I).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top

	Fig. 1. View of (I) with displacement ellipsoids drawn at the 50% probability level. H-atoms are shown by small spheres of arbitrary radius. Hydrogen bonds are symbolized by dashed lines.
	Fig. 2. The partial packing of (I) which shows that molecules form dimers and the dimers are interlinked forming two dimensional polymeric sheets.

2-Hydroxy-3-nitrobenzamide top

Crystal data top

C₇H₆N₂O₄	Z = 4
M_r = 182.14	F(000) = 376
Triclinic, P1	D_x = 1.551 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 3.8390 (2) Å	Cell parameters from 3658 reflections
b = 13.0347 (8) Å	θ = 1.3–27.9°
c = 16.0409 (9) Å	µ = 0.13 mm⁻¹
α = 98.207 (3)°	T = 296 K
β = 95.658 (2)°	Prism, brown
γ = 98.365 (3)°	0.25 × 0.22 × 0.18 mm
V = 780.16 (8) Å³

Data collection top

Bruker Kappa APEXII CCD diffractometer	3658 independent reflections
Radiation source: fine-focus sealed tube	1932 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.039
Detector resolution: 7.40 pixels mm^-1	θ_max = 27.9°, θ_min = 1.3°
ω scans	h = −5→5
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −17→16
T_min = 0.966, T_max = 0.979	l = −20→20
15183 measured reflections

Refinement top

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)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.139	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	w = 1/[σ²(F_o²) + (0.0563P)² + 0.1478P] where P = (F_o² + 2F_c²)/3
3658 reflections	(Δ/σ)_max < 0.001
287 parameters	Δρ_max = 0.19 e Å⁻³
0 restraints	Δρ_min = −0.18 e Å⁻³

Crystal data top

C₇H₆N₂O₄	γ = 98.365 (3)°
M_r = 182.14	V = 780.16 (8) Å³
Triclinic, P1	Z = 4
a = 3.8390 (2) Å	Mo Kα radiation
b = 13.0347 (8) Å	µ = 0.13 mm⁻¹
c = 16.0409 (9) Å	T = 296 K
α = 98.207 (3)°	0.25 × 0.22 × 0.18 mm
β = 95.658 (2)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	3658 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	1932 reflections with I > 2σ(I)
T_min = 0.966, T_max = 0.979	R_int = 0.039
15183 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.048	0 restraints
wR(F²) = 0.139	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	Δρ_max = 0.19 e Å⁻³
3658 reflections	Δρ_min = −0.18 e Å⁻³
287 parameters

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
O5	1.3003 (4)	0.14269 (11)	0.28007 (10)	0.0574 (6)
O6A	1.0846 (17)	0.2123 (3)	0.1437 (3)	0.0622 (16)	0.517 (9)
O7A	0.9012 (16)	0.0976 (4)	0.0315 (3)	0.0726 (16)	0.517 (9)
O8	1.4309 (4)	0.06126 (12)	0.40897 (9)	0.0602 (6)
N3	0.9800 (5)	0.12260 (17)	0.11120 (12)	0.0517 (8)
N4	1.1499 (6)	−0.09612 (17)	0.42380 (13)	0.0584 (7)
C8	1.0438 (5)	−0.03373 (16)	0.28965 (12)	0.0398 (6)
C9	1.1008 (5)	0.05167 (16)	0.24507 (12)	0.0390 (6)
C10	0.9365 (5)	0.03748 (17)	0.16144 (13)	0.0416 (7)
C11	0.7300 (6)	−0.05660 (19)	0.12321 (14)	0.0488 (8)
C12	0.6838 (6)	−0.1393 (2)	0.16654 (14)	0.0522 (8)
C13	0.8391 (6)	−0.12754 (18)	0.24892 (14)	0.0476 (8)
C14	1.2174 (5)	−0.02094 (17)	0.37827 (13)	0.0442 (7)
O7B	1.2731 (16)	0.1761 (5)	0.1186 (3)	0.0686 (17)	0.483 (9)
O6B	0.7212 (15)	0.1376 (4)	0.0676 (4)	0.0765 (19)	0.483 (9)
O1	1.1680 (4)	0.64772 (12)	0.23085 (10)	0.0576 (6)
O2	1.6092 (5)	0.69953 (13)	0.37229 (11)	0.0717 (7)
O3	1.3820 (6)	0.64564 (16)	0.47695 (12)	0.0965 (9)
O4	0.7934 (4)	0.56454 (13)	0.09498 (10)	0.0650 (6)
N1	1.4064 (5)	0.63841 (15)	0.40149 (12)	0.0521 (7)
N2	0.5075 (6)	0.40043 (18)	0.07421 (14)	0.0632 (8)
C1	0.8539 (5)	0.47141 (16)	0.21067 (13)	0.0412 (7)
C2	1.0752 (5)	0.55872 (16)	0.26058 (13)	0.0409 (7)
C3	1.1871 (5)	0.54999 (16)	0.34496 (13)	0.0418 (7)
C4	1.0917 (6)	0.45937 (19)	0.37779 (15)	0.0492 (8)
C5	0.8859 (6)	0.37445 (19)	0.32808 (15)	0.0543 (8)
C6	0.7662 (6)	0.38048 (18)	0.24564 (14)	0.0482 (8)
C7	0.7143 (6)	0.48026 (19)	0.12263 (14)	0.0475 (8)
H4B	0.984 (7)	−0.1544 (19)	0.4054 (15)	0.0701*
H5O	1.38739	0.13813	0.32790	0.0689*
H12	0.533 (7)	−0.208 (2)	0.1414 (15)	0.075 (7)*
H13	0.808 (6)	−0.1821 (18)	0.2792 (14)	0.0571*
H11	0.632 (6)	−0.0653 (17)	0.0674 (15)	0.0586*
H4A	1.260 (7)	−0.0911 (19)	0.4746 (17)	0.0701*
H1O	1.07785	0.64178	0.18153	0.0692*
H2A	0.444 (7)	0.347 (2)	0.0911 (17)	0.0758*
H2B	0.420 (6)	0.4100 (19)	0.0199 (17)	0.0758*
H4	1.161 (6)	0.4557 (17)	0.4324 (15)	0.0589*
H5	0.820 (6)	0.3154 (19)	0.3482 (15)	0.0651*
H6	0.614 (6)	0.3254 (18)	0.2137 (14)	0.0578*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O5	0.0718 (10)	0.0450 (10)	0.0451 (9)	−0.0112 (8)	−0.0179 (8)	0.0107 (7)
O6A	0.079 (3)	0.052 (3)	0.053 (2)	0.000 (2)	−0.002 (2)	0.0178 (19)
O7A	0.075 (3)	0.097 (3)	0.038 (2)	−0.010 (2)	−0.011 (2)	0.021 (2)
O8	0.0729 (10)	0.0528 (10)	0.0431 (9)	−0.0137 (8)	−0.0177 (8)	0.0098 (8)
N3	0.0482 (12)	0.0617 (15)	0.0429 (12)	0.0011 (10)	−0.0054 (9)	0.0157 (11)
N4	0.0716 (14)	0.0557 (13)	0.0403 (11)	−0.0074 (10)	−0.0156 (10)	0.0154 (10)
C8	0.0405 (10)	0.0413 (12)	0.0345 (11)	0.0025 (9)	−0.0022 (9)	0.0042 (10)
C9	0.0362 (10)	0.0402 (12)	0.0362 (11)	0.0001 (9)	−0.0040 (8)	0.0032 (9)
C10	0.0379 (10)	0.0486 (14)	0.0373 (12)	0.0035 (9)	−0.0005 (9)	0.0108 (10)
C11	0.0467 (12)	0.0599 (16)	0.0330 (12)	−0.0004 (11)	−0.0075 (10)	0.0023 (11)
C12	0.0548 (13)	0.0498 (15)	0.0428 (14)	−0.0073 (11)	−0.0062 (10)	0.0011 (12)
C13	0.0542 (13)	0.0437 (14)	0.0406 (13)	−0.0031 (10)	−0.0013 (10)	0.0086 (10)
C14	0.0482 (12)	0.0459 (13)	0.0353 (12)	0.0034 (10)	−0.0036 (9)	0.0062 (10)
O7B	0.060 (3)	0.071 (3)	0.070 (3)	−0.016 (2)	−0.008 (2)	0.033 (2)
O6B	0.064 (3)	0.092 (3)	0.074 (4)	0.010 (2)	−0.020 (3)	0.037 (3)
O1	0.0725 (11)	0.0494 (10)	0.0490 (10)	−0.0047 (8)	−0.0044 (8)	0.0242 (8)
O2	0.0808 (12)	0.0613 (12)	0.0630 (11)	−0.0209 (9)	0.0007 (9)	0.0152 (9)
O3	0.1297 (18)	0.0999 (16)	0.0415 (11)	−0.0298 (13)	−0.0012 (11)	0.0073 (10)
O4	0.0848 (11)	0.0577 (11)	0.0489 (10)	−0.0052 (9)	−0.0095 (8)	0.0257 (8)
N1	0.0565 (11)	0.0520 (12)	0.0454 (12)	0.0023 (9)	−0.0024 (9)	0.0127 (10)
N2	0.0773 (14)	0.0598 (15)	0.0466 (12)	−0.0077 (12)	−0.0122 (10)	0.0217 (11)
C1	0.0417 (11)	0.0458 (13)	0.0385 (12)	0.0082 (9)	0.0049 (9)	0.0141 (10)
C2	0.0428 (11)	0.0416 (12)	0.0412 (12)	0.0061 (9)	0.0066 (9)	0.0160 (10)
C3	0.0416 (11)	0.0439 (13)	0.0406 (12)	0.0054 (9)	0.0041 (9)	0.0117 (10)
C4	0.0521 (12)	0.0568 (15)	0.0406 (13)	0.0065 (11)	0.0005 (10)	0.0206 (12)
C5	0.0604 (14)	0.0493 (15)	0.0530 (15)	−0.0013 (12)	−0.0022 (11)	0.0242 (12)
C6	0.0495 (13)	0.0465 (14)	0.0468 (14)	0.0007 (10)	−0.0010 (10)	0.0137 (11)
C7	0.0494 (12)	0.0520 (14)	0.0424 (13)	0.0063 (11)	0.0028 (10)	0.0158 (11)

Geometric parameters (Å, º) top

O5—C9	1.330 (3)	C8—C13	1.390 (3)
O6A—N3	1.203 (5)	C8—C14	1.485 (3)
O6B—N3	1.214 (6)	C8—C9	1.409 (3)
O7A—N3	1.268 (5)	C9—C10	1.400 (3)
O7B—N3	1.220 (7)	C10—C11	1.384 (3)
O8—C14	1.256 (3)	C11—C12	1.364 (3)
O5—H5O	0.8200	C12—C13	1.373 (3)
O1—C2	1.331 (3)	C11—H11	0.92 (2)
O2—N1	1.208 (3)	C12—H12	1.00 (3)
O3—N1	1.215 (3)	C13—H13	0.92 (2)
O4—C7	1.251 (3)	C1—C7	1.487 (3)
O1—H1O	0.8200	C1—C2	1.408 (3)
N3—C10	1.462 (3)	C1—C6	1.394 (3)
N4—C14	1.315 (3)	C2—C3	1.405 (3)
N4—H4B	0.91 (3)	C3—C4	1.377 (3)
N4—H4A	0.87 (3)	C4—C5	1.362 (3)
N1—C3	1.459 (3)	C5—C6	1.374 (3)
N2—C7	1.313 (3)	C4—H4	0.90 (2)
N2—H2B	0.93 (3)	C5—H5	0.89 (2)
N2—H2A	0.80 (3)	C6—H6	0.91 (2)

C9—O5—H5O	109.00	O8—C14—N4	120.4 (2)
C2—O1—H1O	109.00	O8—C14—C8	119.73 (19)
O6A—N3—C10	121.8 (3)	C10—C11—H11	120.5 (14)
O7A—N3—C10	116.8 (3)	C12—C11—H11	119.2 (14)
O7B—N3—C10	117.3 (3)	C11—C12—H12	122.5 (14)
O6B—N3—O7B	124.6 (4)	C13—C12—H12	118.2 (14)
O6A—N3—O7A	121.4 (4)	C8—C13—H13	117.7 (14)
O6B—N3—C10	118.1 (3)	C12—C13—H13	120.4 (14)
C14—N4—H4A	120.6 (17)	C6—C1—C7	122.08 (19)
H4A—N4—H4B	116 (2)	C2—C1—C6	119.27 (19)
C14—N4—H4B	123.0 (15)	C2—C1—C7	118.64 (19)
O2—N1—C3	119.37 (18)	O1—C2—C3	120.55 (18)
O3—N1—C3	117.86 (19)	C1—C2—C3	117.33 (19)
O2—N1—O3	122.7 (2)	O1—C2—C1	122.09 (18)
H2A—N2—H2B	120 (2)	N1—C3—C2	120.54 (18)
C7—N2—H2B	117.6 (15)	N1—C3—C4	117.60 (19)
C7—N2—H2A	122.1 (19)	C2—C3—C4	121.9 (2)
C9—C8—C13	119.43 (18)	C3—C4—C5	120.2 (2)
C13—C8—C14	122.27 (19)	C4—C5—C6	119.7 (2)
C9—C8—C14	118.26 (18)	C1—C6—C5	121.6 (2)
O5—C9—C10	120.59 (19)	O4—C7—C1	119.6 (2)
C8—C9—C10	117.21 (19)	N2—C7—C1	120.3 (2)
O5—C9—C8	122.19 (17)	O4—C7—N2	120.1 (2)
N3—C10—C11	117.63 (19)	C3—C4—H4	120.7 (15)
N3—C10—C9	120.55 (19)	C5—C4—H4	119.1 (14)
C9—C10—C11	121.8 (2)	C4—C5—H5	121.6 (15)
C10—C11—C12	120.3 (2)	C6—C5—H5	118.7 (15)
C11—C12—C13	119.3 (2)	C1—C6—H6	118.7 (15)
C8—C13—C12	122.0 (2)	C5—C6—H6	119.6 (15)
N4—C14—C8	119.9 (2)

O6A—N3—C10—C9	−17.2 (5)	C9—C10—C11—C12	−0.6 (3)
O6A—N3—C10—C11	163.1 (4)	N3—C10—C11—C12	179.1 (2)
O7A—N3—C10—C9	163.0 (4)	C10—C11—C12—C13	1.2 (4)
O7A—N3—C10—C11	−16.7 (4)	C11—C12—C13—C8	−0.2 (4)
O2—N1—C3—C2	−30.7 (3)	C6—C1—C2—O1	−179.93 (18)
O2—N1—C3—C4	150.2 (2)	C6—C1—C2—C3	−2.0 (3)
O3—N1—C3—C2	151.1 (2)	C7—C1—C2—O1	−1.3 (3)
O3—N1—C3—C4	−28.0 (3)	C7—C1—C2—C3	176.59 (19)
C13—C8—C9—C10	1.7 (3)	C2—C1—C6—C5	1.0 (3)
C14—C8—C9—O5	−0.7 (3)	C7—C1—C6—C5	−177.5 (2)
C13—C8—C9—O5	−178.57 (19)	C2—C1—C7—O4	−0.5 (3)
C9—C8—C14—N4	175.1 (2)	C2—C1—C7—N2	179.9 (2)
C13—C8—C14—O8	172.1 (2)	C6—C1—C7—O4	178.1 (2)
C13—C8—C14—N4	−7.1 (3)	C6—C1—C7—N2	−1.5 (3)
C14—C8—C13—C12	−179.0 (2)	O1—C2—C3—N1	0.1 (3)
C14—C8—C9—C10	179.55 (18)	O1—C2—C3—C4	179.2 (2)
C9—C8—C13—C12	−1.3 (3)	C1—C2—C3—N1	−177.82 (18)
C9—C8—C14—O8	−5.6 (3)	C1—C2—C3—C4	1.3 (3)
O5—C9—C10—N3	−0.3 (3)	N1—C3—C4—C5	179.7 (2)
O5—C9—C10—C11	179.5 (2)	C2—C3—C4—C5	0.6 (3)
C8—C9—C10—N3	179.46 (18)	C3—C4—C5—C6	−1.7 (4)
C8—C9—C10—C11	−0.8 (3)	C4—C5—C6—C1	0.9 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O···O4	0.82	1.77	2.500 (2)	148
N2—H2A···O6Aⁱ	0.80 (3)	2.38 (3)	3.142 (5)	161 (3)
N2—H2B···O4ⁱⁱ	0.93 (3)	2.03 (3)	2.966 (3)	177 (2)
N4—H4A···O8ⁱⁱⁱ	0.87 (3)	2.07 (3)	2.929 (3)	172 (2)
N4—H4B···O2^iv	0.91 (3)	2.18 (3)	3.084 (3)	174 (2)
O5—H5O···O8	0.82	1.76	2.496 (2)	148
C6—H6···O6Aⁱ	0.91 (2)	2.40 (2)	3.285 (6)	163 (2)
C11—H11···O7A^v	0.92 (2)	2.41 (2)	3.221 (6)	147 (2)
C11—H11···O7A^vi	0.92 (2)	2.55 (2)	2.997 (6)	110.5 (17)
C13—H13···O2^iv	0.92 (2)	2.39 (2)	3.289 (3)	165 (2)

Symmetry codes: (i) x−1, y, z; (ii) −x+1, −y+1, −z; (iii) −x+3, −y, −z+1; (iv) x−1, y−1, z; (v) −x+1, −y, −z; (vi) −x+2, −y, −z.

Experimental details

Crystal data
Chemical formula	C₇H₆N₂O₄
M_r	182.14
Crystal system, space group	Triclinic, P1
Temperature (K)	296
a, b, c (Å)	3.8390 (2), 13.0347 (8), 16.0409 (9)
α, β, γ (°)	98.207 (3), 95.658 (2), 98.365 (3)
V (Å³)	780.16 (8)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.13
Crystal size (mm)	0.25 × 0.22 × 0.18

Data collection
Diffractometer	Bruker Kappa APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.966, 0.979
No. of measured, independent and observed [I > 2σ(I)] reflections	15183, 3658, 1932
R_int	0.039
(sin θ/λ)_max (Å⁻¹)	0.658

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.048, 0.139, 1.00
No. of reflections	3658
No. of parameters	287
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.19, −0.18

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O···O4	0.82	1.77	2.500 (2)	148
N2—H2A···O6Aⁱ	0.80 (3)	2.38 (3)	3.142 (5)	161 (3)
N2—H2B···O4ⁱⁱ	0.93 (3)	2.03 (3)	2.966 (3)	177 (2)
N4—H4A···O8ⁱⁱⁱ	0.87 (3)	2.07 (3)	2.929 (3)	172 (2)
N4—H4B···O2^iv	0.91 (3)	2.18 (3)	3.084 (3)	174 (2)
O5—H5O···O8	0.82	1.76	2.496 (2)	148
C6—H6···O6Aⁱ	0.91 (2)	2.40 (2)	3.285 (6)	163 (2)
C11—H11···O7A^v	0.92 (2)	2.41 (2)	3.221 (6)	147 (2)
C11—H11···O7A^vi	0.92 (2)	2.55 (2)	2.997 (6)	110.5 (17)
C13—H13···O2^iv	0.92 (2)	2.39 (2)	3.289 (3)	165 (2)

Symmetry codes: (i) x−1, y, z; (ii) −x+1, −y+1, −z; (iii) −x+3, −y, −z+1; (iv) x−1, y−1, z; (v) −x+1, −y, −z; (vi) −x+2, −y, −z.

Acknowledgements

The authors acknowledge the Higher Education Commission, Islamabad, Pakistan, and Bana International, Karachi, Pakistan, for funding the purchase of the diffractometer at GCU, Lahore and for technical support, respectively.

References

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