3,5-Dinitro­pyridin-4(1H)-one monohydrate

Li, Y.; Li, P.; Zhou, Q.-P.; Zhang, G.-F.; Ng, S.W.

doi:10.1107/S1600536808024604

organic compounds

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ISSN: 2056-9890

Volume 64| Part 9| September 2008| Page o1701

doi:10.1107/S1600536808024604

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3,5-Dinitropyridin-4(1H)-one monohydrate

Ying Li,^a Ping Li,^a Qiu-Ping Zhou,^b Guo-Fang Zhang ^b and Seik Weng Ng ^c ^*

^aChemistry Department, Jingning Normal College, Wulanchabu, Inner Mongolia 012000, People's Republic of China, ^bSchool of Chemistry and Materials Science, Shaanxi Normal University, Xi'an 710062, People's Republic of China, and ^cDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: seikweng@um.edu.my

(Received 25 July 2008; accepted 31 July 2008; online 6 August 2008)

The three independent organic molecules of 3,5-dinitropyridin-4(1H)-one monohydrate, C₅H₃N₃O₅·H₂O, each feature an N—H⋯O_water hydrogen bond. Each water molecule serves as hydrogen-bond donor to two carbonyl O atoms; these hydrogen bonds give rise to a layer motif. Two of the three formula units lie on special positions of site symmetry 2.

Related literature

The parent pyridin-4-one homolog crystallizes with five pyridone and six water molecules in the asymmetric unit; see: Jones (2001 ).

Experimental

Crystal data

C₅H₃N₃O₅·H₂O
M_r = 203.12
Orthorhombic, P b c n
a = 21.728 (2) Å
b = 21.654 (2) Å
c = 6.5713 (5) Å
V = 3091.7 (4) Å³
Z = 16
Mo Kα radiation
μ = 0.16 mm⁻¹
T = 293 (2) K
0.45 × 0.45 × 0.20 mm

Data collection

Bruker APEXII diffractometer
Absorption correction: none
21800 measured reflections
3555 independent reflections
2852 reflections with I > 2σ(I)
R_int = 0.022

Refinement

R[F² > 2σ(F²)] = 0.040
wR(F²) = 0.123
S = 1.08
3555 reflections
281 parameters
10 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.34 e Å⁻³
Δρ_min = −0.31 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3⋯O1w	0.85 (1)	1.86 (1)	2.703 (2)	172 (2)
N5—H5⋯O2w	0.85 (1)	1.84 (1)	2.692 (3)	180
N6—H6⋯O3w	0.85 (1)	1.87 (1)	2.723 (3)	180
O1w—H11⋯O8ⁱ	0.85 (1)	2.04 (1)	2.878 (2)	168 (2)
O1w—H12⋯O11ⁱⁱ	0.86 (1)	2.02 (1)	2.866 (2)	168 (2)
O2w—H21⋯O3ⁱⁱⁱ	0.84 (1)	2.05 (1)	2.888 (2)	173 (1)
O3w—H31⋯O3	0.84 (1)	2.05 (1)	2.890 (2)	172 (2)
Symmetry codes: (i) $[-x+{\script{3\over 2}}, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]$ ; (ii) $[x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (iii) -x+1, -y+1, -z+1.

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: X-SEED (Barbour, 2001 ); software used to prepare material for publication: publCIF (Westrip, 2008 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808024604/pk2110sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808024604/pk2110Isup2.hkl

checkCIF report

Comment top

3,5-Dinitro-4-pyridinol, a specialty chemical, is assumed in chemical catalogs to exist in the enol form. The homolog, 4-pyridinol, is in fact 4-pyridinone^.6/5hydrate. It has five independent pyridone and six water molecules that are hydrogen bonded to form layers (Jones, 2001). The presence of two electron-withdrawing groups in the title compound should enhance its propensity to form hydrogen bonds, and this is borne out in the present study. The three independent molecules of 3,5-dinitro-1H-pyridin-4-one hydrate (Fig. 1) each feature an N–H···O_water hydrogen bond; each water molecule serves as hydrogen-bond donor to two carbonyl oxygen atoms, and these hydrogen bonds give rise to a layered structure.

Related literature top

The parent pyridin-4-one homolog crystallizes with five pyridone and six water molecules in the asymmetric unit; see: Jones (2001).

Experimental top

4-Hydroxy-3-pyridine (19 g, 0.02 mol) was dissolved in fuming sulfuric acid (50% by SO₃ content) (60 ml), and to the solution was added an oleum-fuming nitric acid (1/3) mixture (50 ml). The temperature was kept at 0°C for an hour. The temperature was raised to 413 K over a period of one hour, and then held at 403 K for another 16 h. The mixture was poured into ice (200 g) to quench the reaction. Some 27 g of material was isolated. Crystals were obtained by recrystallization from water.

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: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2008).

Figures top

Fig. 1. Thermal ellipsoid plot (Barbour, 2001) plot of the three independent molecules of C₅H₃N₃O₅^.H₂O at the 50% probability level. Hydrogen atoms are drawn as spheres of arbitrary radius.

3,5-Dinitropyridin-4(1H)-one monohydrate top

Crystal data top

C₅H₃N₃O₅·H₂O	F(000) = 1664
M_r = 203.12	D_x = 1.746 Mg m⁻³
Orthorhombic, Pbcn	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2n 2ab	Cell parameters from 6494 reflections
a = 21.728 (2) Å	θ = 2.7–27.9°
b = 21.654 (2) Å	µ = 0.16 mm⁻¹
c = 6.5713 (5) Å	T = 293 K
V = 3091.7 (4) Å³	Block, colorless
Z = 16	0.45 × 0.45 × 0.20 mm

Data collection top

Bruker APEXII diffractometer	2852 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.022
Graphite monochromator	θ_max = 27.5°, θ_min = 2.7°
Detector resolution: 9 pixels mm^-1	h = −28→27
ϕ and ω scans	k = −28→27
21800 measured reflections	l = −8→8
3555 independent 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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.123	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	w = 1/[σ²(F_o²) + (0.0528P)² + 1.6904P] where P = (F_o² + 2F_c²)/3
3555 reflections	(Δ/σ)_max < 0.001
281 parameters	Δρ_max = 0.35 e Å⁻³
10 restraints	Δρ_min = −0.31 e Å⁻³

Crystal data top

C₅H₃N₃O₅·H₂O	V = 3091.7 (4) Å³
M_r = 203.12	Z = 16
Orthorhombic, Pbcn	Mo Kα radiation
a = 21.728 (2) Å	µ = 0.16 mm⁻¹
b = 21.654 (2) Å	T = 293 K
c = 6.5713 (5) Å	0.45 × 0.45 × 0.20 mm

Data collection top

Bruker APEXII diffractometer	2852 reflections with I > 2σ(I)
21800 measured reflections	R_int = 0.022
3555 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.040	10 restraints
wR(F²) = 0.123	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	Δρ_max = 0.35 e Å⁻³
3555 reflections	Δρ_min = −0.31 e Å⁻³
281 parameters

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

	x	y	z	U_iso*/U_eq
O1	0.69961 (7)	0.46193 (6)	0.2892 (3)	0.0552 (4)
O2	0.62136 (6)	0.50982 (6)	0.4163 (3)	0.0464 (4)
O3	0.60319 (6)	0.62125 (6)	0.2292 (2)	0.0431 (4)
O4	0.61633 (6)	0.73545 (6)	0.0695 (3)	0.0486 (4)
O5	0.70310 (8)	0.77792 (8)	0.1081 (6)	0.1176 (12)
O6	0.60858 (6)	0.75858 (6)	0.5467 (3)	0.0496 (4)
O7	0.65774 (6)	0.67898 (7)	0.6579 (3)	0.0562 (4)
O8	0.5000	0.77618 (7)	0.7500	0.0389 (4)
O9	0.65904 (7)	0.92189 (7)	0.1991 (3)	0.0659 (5)
O10	0.61401 (6)	1.00203 (6)	0.0759 (3)	0.0482 (4)
O11	0.5000	1.02039 (7)	0.2500	0.0357 (4)
O1W	0.91543 (6)	0.62174 (6)	0.2293 (3)	0.0507 (4)
O2W	0.5000	0.46255 (9)	0.7500	0.0627 (7)
O3W	0.5000	0.70522 (8)	0.2500	0.0416 (5)
N1	0.67114 (7)	0.50953 (7)	0.3278 (3)	0.0360 (3)
N2	0.67066 (7)	0.73271 (7)	0.1089 (3)	0.0435 (4)
N3	0.79137 (7)	0.61956 (8)	0.1992 (3)	0.0434 (4)
N4	0.61008 (6)	0.70807 (7)	0.6311 (3)	0.0357 (3)
N5	0.5000	0.58686 (9)	0.7500	0.0376 (5)
N6	0.5000	0.83100 (9)	0.2500	0.0384 (5)
N7	0.61264 (7)	0.95139 (7)	0.1582 (3)	0.0377 (4)
C1	0.76100 (8)	0.56854 (9)	0.2549 (3)	0.0390 (4)
H1A	0.7829	0.5329	0.2857	0.047*
C2	0.69872 (8)	0.56805 (8)	0.2672 (3)	0.0315 (4)
C3	0.65995 (8)	0.62114 (7)	0.2208 (3)	0.0302 (4)
C4	0.69804 (8)	0.67347 (8)	0.1610 (3)	0.0337 (4)
C5	0.76066 (8)	0.67135 (9)	0.1539 (3)	0.0405 (4)
H5A	0.7825	0.7065	0.1169	0.049*
C6	0.55166 (8)	0.61756 (8)	0.7027 (3)	0.0345 (4)
H6A	0.5874	0.5957	0.6733	0.041*
C7	0.55244 (7)	0.68038 (7)	0.6972 (3)	0.0290 (4)
C8	0.5000	0.71922 (10)	0.7500	0.0269 (5)
C9	0.55223 (9)	0.86172 (8)	0.2128 (3)	0.0360 (4)
H9	0.5884	0.8398	0.1893	0.043*
C10	0.55324 (8)	0.92451 (7)	0.2090 (3)	0.0301 (4)
C11	0.5000	0.96327 (10)	0.2500	0.0278 (5)
H11	0.9376 (8)	0.6540 (6)	0.220 (4)	0.059 (7)*
H12	0.9385 (8)	0.5898 (6)	0.218 (4)	0.053 (7)*
H21	0.4680 (2)	0.4409 (7)	0.757 (4)	0.055 (7)*
H31	0.5318 (3)	0.6832 (7)	0.236 (4)	0.058 (7)*
H3	0.8306 (5)	0.6181 (10)	0.199 (4)	0.057 (7)*
H5	0.5000	0.5477 (5)	0.7500	0.051 (9)*
H6	0.5000	0.7915 (5)	0.2500	0.051 (9)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0543 (9)	0.0322 (7)	0.0790 (12)	0.0112 (6)	0.0045 (8)	0.0018 (7)
O2	0.0369 (7)	0.0417 (7)	0.0607 (9)	−0.0020 (6)	0.0068 (7)	0.0077 (7)
O3	0.0218 (6)	0.0344 (7)	0.0730 (10)	0.0014 (5)	0.0029 (6)	0.0061 (6)
O4	0.0381 (7)	0.0401 (7)	0.0676 (10)	0.0086 (6)	−0.0039 (7)	0.0016 (7)
O5	0.0504 (10)	0.0435 (10)	0.259 (4)	−0.0121 (8)	−0.0082 (15)	0.0441 (15)
O6	0.0415 (7)	0.0392 (7)	0.0681 (10)	−0.0090 (6)	0.0128 (7)	0.0059 (7)
O7	0.0273 (7)	0.0575 (9)	0.0837 (12)	0.0076 (6)	0.0053 (7)	−0.0044 (8)
O8	0.0326 (9)	0.0211 (8)	0.0631 (13)	0.000	0.0069 (8)	0.000
O9	0.0304 (7)	0.0501 (9)	0.1171 (16)	0.0104 (6)	0.0009 (8)	0.0031 (9)
O10	0.0399 (7)	0.0372 (7)	0.0673 (10)	−0.0056 (6)	0.0073 (7)	0.0088 (7)
O11	0.0305 (9)	0.0199 (8)	0.0567 (12)	0.000	0.0020 (8)	0.000
O1W	0.0263 (7)	0.0294 (7)	0.0962 (13)	0.0008 (5)	−0.0054 (7)	0.0013 (7)
O2W	0.0296 (10)	0.0253 (9)	0.133 (2)	0.000	−0.0014 (12)	0.000
O3W	0.0286 (9)	0.0244 (8)	0.0719 (14)	0.000	0.0004 (9)	0.000
N1	0.0345 (8)	0.0322 (8)	0.0414 (9)	0.0028 (6)	−0.0042 (7)	0.0014 (6)
N2	0.0356 (8)	0.0335 (8)	0.0614 (11)	−0.0008 (6)	0.0060 (8)	0.0067 (7)
N3	0.0206 (7)	0.0488 (10)	0.0608 (11)	0.0008 (6)	−0.0006 (7)	0.0012 (8)
N4	0.0275 (7)	0.0353 (8)	0.0442 (9)	−0.0025 (6)	0.0039 (6)	−0.0084 (7)
N5	0.0434 (12)	0.0192 (9)	0.0503 (14)	0.000	0.0058 (10)	0.000
N6	0.0460 (13)	0.0188 (9)	0.0504 (13)	0.000	0.0006 (10)	0.000
N7	0.0293 (7)	0.0333 (8)	0.0505 (10)	0.0011 (6)	0.0040 (7)	−0.0052 (7)
C1	0.0282 (9)	0.0412 (10)	0.0476 (11)	0.0067 (7)	−0.0031 (8)	−0.0008 (8)
C2	0.0270 (8)	0.0305 (8)	0.0371 (9)	0.0010 (6)	−0.0011 (7)	−0.0017 (7)
C3	0.0237 (8)	0.0296 (8)	0.0374 (9)	0.0006 (6)	0.0012 (7)	−0.0023 (7)
C4	0.0264 (8)	0.0324 (9)	0.0424 (10)	0.0001 (7)	0.0008 (7)	0.0007 (7)
C5	0.0288 (9)	0.0410 (10)	0.0517 (12)	−0.0062 (7)	0.0027 (8)	0.0011 (9)
C6	0.0339 (9)	0.0289 (8)	0.0406 (10)	0.0063 (7)	0.0034 (7)	−0.0019 (7)
C7	0.0261 (8)	0.0269 (8)	0.0339 (9)	−0.0002 (6)	0.0009 (7)	−0.0015 (6)
C8	0.0258 (11)	0.0233 (10)	0.0316 (12)	0.000	−0.0020 (9)	0.000
C9	0.0387 (10)	0.0270 (8)	0.0421 (10)	0.0055 (7)	0.0003 (8)	−0.0018 (7)
C10	0.0296 (8)	0.0239 (8)	0.0369 (9)	0.0001 (6)	−0.0006 (7)	−0.0009 (6)
C11	0.0281 (11)	0.0228 (10)	0.0323 (12)	0.000	−0.0021 (9)	0.000

Geometric parameters (Å, º) top

O1—N1	1.2285 (19)	N5—C6	1.341 (2)
O2—N1	1.228 (2)	N5—C6ⁱ	1.341 (2)
O3—C3	1.235 (2)	N5—H5	0.848 (10)
O4—N2	1.210 (2)	N6—C9	1.338 (2)
O5—N2	1.206 (2)	N6—C9ⁱⁱ	1.338 (2)
O6—N4	1.227 (2)	N6—H6	0.854 (10)
O7—N4	1.225 (2)	N7—C10	1.455 (2)
O8—C8	1.233 (3)	C1—C2	1.356 (2)
O9—N7	1.223 (2)	C1—H1A	0.9300
O10—N7	1.223 (2)	C2—C3	1.457 (2)
O11—C11	1.237 (3)	C3—C4	1.457 (2)
O1W—H11	0.851 (9)	C4—C5	1.362 (2)
O1W—H12	0.858 (9)	C5—H5A	0.9300
O2W—H21	0.840 (8)	C6—C7	1.361 (2)
O3W—H31	0.844 (8)	C6—H6A	0.9300
N1—C2	1.457 (2)	C7—C8	1.458 (2)
N2—C4	1.455 (2)	C8—C7ⁱ	1.458 (2)
N3—C1	1.338 (3)	C9—C10	1.360 (2)
N3—C5	1.338 (3)	C9—H9	0.9300
N3—H3	0.853 (10)	C10—C11	1.454 (2)
N4—C7	1.455 (2)	C11—C10ⁱⁱ	1.454 (2)

H11—O1W—H12	109.1 (14)	O3—C3—C4	125.31 (15)
O2—N1—O1	123.08 (16)	O3—C3—C2	124.72 (15)
O2—N1—C2	119.15 (14)	C4—C3—C2	109.97 (14)
O1—N1—C2	117.76 (15)	C5—C4—N2	115.48 (16)
O5—N2—O4	121.96 (17)	C5—C4—C3	123.38 (16)
O5—N2—C4	118.53 (17)	N2—C4—C3	121.12 (15)
O4—N2—C4	119.51 (15)	N3—C5—C4	121.24 (17)
C1—N3—C5	120.47 (16)	N3—C5—H5A	119.4
C1—N3—H3	117.6 (16)	C4—C5—H5A	119.4
C5—N3—H3	121.8 (16)	N5—C6—C7	120.80 (16)
O7—N4—O6	123.11 (15)	N5—C6—H6A	119.6
O7—N4—C7	118.20 (15)	C7—C6—H6A	119.6
O6—N4—C7	118.66 (14)	C6—C7—N4	115.51 (15)
C6—N5—C6ⁱ	120.6 (2)	C6—C7—C8	124.09 (16)
C6—N5—H5	119.71 (10)	N4—C7—C8	120.39 (14)
C6ⁱ—N5—H5	119.71 (10)	O8—C8—C7ⁱ	125.23 (9)
C9—N6—C9ⁱⁱ	120.4 (2)	O8—C8—C7	125.23 (9)
C9—N6—H6	119.82 (11)	C7ⁱ—C8—C7	109.54 (19)
C9ⁱⁱ—N6—H6	119.82 (10)	N6—C9—C10	120.94 (17)
O10—N7—O9	123.05 (16)	N6—C9—H9	119.5
O10—N7—C10	118.79 (14)	C10—C9—H9	119.5
O9—N7—C10	118.16 (16)	C9—C10—C11	124.11 (16)
N3—C1—C2	120.99 (17)	C9—C10—N7	114.74 (15)
N3—C1—H1A	119.5	C11—C10—N7	121.15 (14)
C2—C1—H1A	119.5	O11—C11—C10ⁱⁱ	125.25 (9)
C1—C2—N1	115.69 (15)	O11—C11—C10	125.25 (9)
C1—C2—C3	123.94 (16)	C10ⁱⁱ—C11—C10	109.50 (19)
N1—C2—C3	120.36 (14)

C5—N3—C1—C2	−0.1 (3)	C6ⁱ—N5—C6—C7	−1.47 (13)
N3—C1—C2—N1	179.48 (18)	N5—C6—C7—N4	−176.15 (14)
N3—C1—C2—C3	0.5 (3)	N5—C6—C7—C8	3.0 (3)
O2—N1—C2—C1	152.19 (18)	O7—N4—C7—C6	−26.7 (2)
O1—N1—C2—C1	−27.0 (3)	O6—N4—C7—C6	151.55 (18)
O2—N1—C2—C3	−28.8 (3)	O7—N4—C7—C8	154.12 (15)
O1—N1—C2—C3	151.95 (18)	O6—N4—C7—C8	−27.7 (2)
C1—C2—C3—O3	179.23 (19)	C6—C7—C8—O8	178.50 (13)
N1—C2—C3—O3	0.3 (3)	N4—C7—C8—O8	−2.34 (18)
C1—C2—C3—C4	−0.1 (3)	C6—C7—C8—C7ⁱ	−1.50 (13)
N1—C2—C3—C4	−179.00 (16)	N4—C7—C8—C7ⁱ	177.66 (18)
O5—N2—C4—C5	−16.1 (3)	C9ⁱⁱ—N6—C9—C10	−0.98 (13)
O4—N2—C4—C5	164.46 (19)	N6—C9—C10—C11	2.0 (3)
O5—N2—C4—C3	162.5 (3)	N6—C9—C10—N7	−177.52 (15)
O4—N2—C4—C3	−16.9 (3)	O10—N7—C10—C9	152.08 (18)
O3—C3—C4—C5	179.9 (2)	O9—N7—C10—C9	−27.5 (3)
C2—C3—C4—C5	−0.7 (3)	O10—N7—C10—C11	−27.5 (2)
O3—C3—C4—N2	1.4 (3)	O9—N7—C10—C11	152.96 (17)
C2—C3—C4—N2	−179.23 (17)	C9—C10—C11—O11	179.01 (13)
C1—N3—C5—C4	−0.7 (3)	N7—C10—C11—O11	−1.48 (19)
N2—C4—C5—N3	179.75 (19)	C9—C10—C11—C10ⁱⁱ	−0.99 (13)
C3—C4—C5—N3	1.2 (3)	N7—C10—C11—C10ⁱⁱ	178.52 (19)

Symmetry codes: (i) −x+1, y, −z+3/2; (ii) −x+1, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3···O1w	0.85 (1)	1.86 (1)	2.703 (2)	172 (2)
N5—H5···O2w	0.85 (1)	1.84 (1)	2.692 (3)	180
N6—H6···O3w	0.85 (1)	1.87 (1)	2.723 (3)	180
O1w—H11···O8ⁱⁱⁱ	0.85 (1)	2.04 (1)	2.878 (2)	168 (2)
O1w—H12···O11^iv	0.86 (1)	2.02 (1)	2.866 (2)	168 (2)
O2w—H21···O3^v	0.84 (1)	2.05 (1)	2.888 (2)	173 (1)
O3w—H31···O3	0.84 (1)	2.05 (1)	2.890 (2)	172 (2)

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

Experimental details

Crystal data
Chemical formula	C₅H₃N₃O₅·H₂O
M_r	203.12
Crystal system, space group	Orthorhombic, Pbcn
Temperature (K)	293
a, b, c (Å)	21.728 (2), 21.654 (2), 6.5713 (5)
V (Å³)	3091.7 (4)
Z	16
Radiation type	Mo Kα
µ (mm⁻¹)	0.16
Crystal size (mm)	0.45 × 0.45 × 0.20

Data collection
Diffractometer	Bruker APEXII diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	21800, 3555, 2852
R_int	0.022
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.040, 0.123, 1.08
No. of reflections	3555
No. of parameters	281
No. of restraints	10
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.35, −0.31

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3···O1w	0.85 (1)	1.86 (1)	2.703 (2)	172 (2)
N5—H5···O2w	0.85 (1)	1.84 (1)	2.692 (3)	180
N6—H6···O3w	0.85 (1)	1.87 (1)	2.723 (3)	180
O1w—H11···O8ⁱ	0.85 (1)	2.04 (1)	2.878 (2)	168 (2)
O1w—H12···O11ⁱⁱ	0.86 (1)	2.02 (1)	2.866 (2)	168 (2)
O2w—H21···O3ⁱⁱⁱ	0.84 (1)	2.05 (1)	2.888 (2)	173 (1)
O3w—H31···O3	0.84 (1)	2.05 (1)	2.890 (2)	172 (2)

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

Acknowledgements

We thank Jingning Normal College, Shaanxi Normal University and the University of Malaya for supporting this study.

References

Barbour, L. J. (2001). J. Supramol. Chem. 1, 189–191. CrossRef CAS Google Scholar
Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Jones, P. G. (2001). Acta Cryst. C57, 880–882. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Westrip, S. P. (2008). publCIF. In preparation. Google Scholar