2-(3-Hy­droxy­benzyl­amino)­acetic acid

Zhi, L.-H.; Wu, W.-N.

doi:10.1107/S1600536811024226

organic compounds

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ISSN: 2056-9890

Volume 67| Part 7| July 2011| Page o1791

doi:10.1107/S1600536811024226

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2-(3-Hydroxybenzylamino)acetic acid

Li-Hua Zhi ^a and Wei-Na Wu ^a ^*

^aDepartment of Physics and Chemistry, Henan Polytechnic University, Jiaozuo 454000, People's Republic of China
^*Correspondence e-mail: wuwn08@hpu.edu.cn

(Received 4 June 2011; accepted 20 June 2011; online 25 June 2011)

There are two independent 2-(3-hydroxybenzylamino)acetic acid molecules, C₉H₁₁NO₃, in the asymmetric unit of the title compound. The dihedral angle between the benzene rings of the two independent molecules is 58.12 (4)°. The crystal packing is stablized by intermolecular O—H⋯O and N—H⋯O hydrogen bonds.

Related literature

For the anti-tumor and artificial nuclease activity of copper complexes with substituted amino acid ligands, see: Jia et al. (2010 ).

Experimental

Crystal data

C₉H₁₁NO₃
M_r = 181.19
Monoclinic, P c
a = 11.9779 (3) Å
b = 8.0267 (2) Å
c = 9.3835 (2) Å
β = 101.391 (2)°
V = 884.39 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 296 K
0.23 × 0.16 × 0.12 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2007 ) T_min = 0.980, T_max = 0.988
7436 measured reflections
1999 independent reflections
1815 reflections with I > 2σ(I)
R_int = 0.022

Refinement

R[F² > 2σ(F²)] = 0.043
wR(F²) = 0.134
S = 1.07
1999 reflections
235 parameters
2 restraints
H-atom parameters constrained
Δρ_max = 0.40 e Å⁻³
Δρ_min = −0.32 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O4	0.86	2.25	2.891 (3)	132
O3—H3C⋯O2ⁱ	0.82	1.84	2.639 (4)	166
N2—H2C⋯O2ⁱⁱ	0.86	2.28	2.910 (3)	130
O6—H6A⋯O4ⁱⁱⁱ	0.82	1.85	2.646 (4)	165
Symmetry codes: (i) $[x, -y+1, z-{\script{1\over 2}}]$ ; (ii) x, y, z-1; (iii) $[x, -y, z-{\script{1\over 2}}]$ .

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: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811024226/vm2101sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811024226/vm2101Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811024226/vm2101Isup3.cml

checkCIF report

Comment top

In recent years, substituted amino acid complexes have received extensive attention because of primarily their biological and pharmaceutical activities (Lei Jia et al., 2010). As part of our studies of substituted amino acids, the title compound was synthesized and characterized by X-ray diffraction.

The asymmetric of the title compound, 2C₉H₁₁NO₃, contains two independent 2-(3-hydroxybenzylamino)acetic acid molecules (Fig. 1). Each benzene ring is essentially planar [mean deviations of 0.0066 Å for ring C4—C9 and 0.0030 Å for ring C13—C18]. The torsion angles C12—N2 –C11—C10 and C2—N1—C3—C4 are -163.2 (2)° and -55.5 (3)°, respectively. The dihedral angle between the benzene rings in two independent amino acid molecules is 58.12 (4)°. In the crystal structure, intermolecular O—H···O and N—H···O hydrogen bonds are helpful to stabilize the packing (Table 1, Fig. 2).

Related literature top

For the anti-tumor and artificial nuclease activity of copper complexes with substituted amino acid ligands, see: Jia et al. (2010).

Experimental top

To a clear solution of glycine (0.75 g, 10 mmol) and NaOH (0.40 g, 10 mmol) in a solvent mixture of water (10 mL) and methanol (20 mL), was added 3-hydroxy benzaldehyde (1.22 g, 10 mmol) and the resulting yellow solution was stirred for 3 h. After cooling to 273 K, a slight excess of NaBH₄ (0.46 g, 12 mmol) was added. The yellow color slowly discharged after 20–30 min and the pH value was maintained 5–6 by addition of acetic acid. Colorless blocks of the title compound were obtained by slow evaporation of the reaction mixture.

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: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The title compound with the displacement ellipsoids shown at the 50% probability level.
	Fig. 2. Part of the crystal packing for the title compound [hydrogen bonds shown as dashed lines, with symmetry codes: (i) x, -y + 1, z - 1/2; (ii) x, y, z - 1; (iii) x, -y, z - 1/2.].

2-(3-Hydroxybenzylamino)acetic acid top

Crystal data top

C₉H₁₁NO₃	F(000) = 384
M_r = 181.19	D_x = 1.361 Mg m⁻³
Monoclinic, Pc	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P -2yc	Cell parameters from 3325 reflections
a = 11.9779 (3) Å	θ = 3.1–26.5°
b = 8.0267 (2) Å	µ = 0.10 mm⁻¹
c = 9.3835 (2) Å	T = 296 K
β = 101.391 (2)°	Block, colorless
V = 884.39 (4) Å³	0.23 × 0.16 × 0.12 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	1999 independent reflections
Radiation source: fine-focus sealed tube	1815 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.022
ϕ and ω scans	θ_max = 27.4°, θ_min = 1.7°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −15→14
T_min = 0.980, T_max = 0.988	k = −10→10
7436 measured reflections	l = −12→12

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)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.134	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0892P)² + 0.1326P] where P = (F_o² + 2F_c²)/3
1999 reflections	(Δ/σ)_max = 0.007
235 parameters	Δρ_max = 0.40 e Å⁻³
2 restraints	Δρ_min = −0.32 e Å⁻³

Crystal data top

C₉H₁₁NO₃	V = 884.39 (4) Å³
M_r = 181.19	Z = 4
Monoclinic, Pc	Mo Kα radiation
a = 11.9779 (3) Å	µ = 0.10 mm⁻¹
b = 8.0267 (2) Å	T = 296 K
c = 9.3835 (2) Å	0.23 × 0.16 × 0.12 mm
β = 101.391 (2)°

Data collection top

Bruker APEXII CCD diffractometer	1999 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2007)	1815 reflections with I > 2σ(I)
T_min = 0.980, T_max = 0.988	R_int = 0.022
7436 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	2 restraints
wR(F²) = 0.134	H-atom parameters constrained
S = 1.07	Δρ_max = 0.40 e Å⁻³
1999 reflections	Δρ_min = −0.32 e Å⁻³
235 parameters

Special details top

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.

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

	x	y	z	U_iso*/U_eq
O2	0.55759 (19)	0.0934 (3)	0.6066 (2)	0.0384 (5)
N1	0.6095 (2)	0.2130 (3)	0.2543 (3)	0.0336 (5)
H1A	0.5405	0.2099	0.2063	0.040*
C1	0.5447 (3)	0.0976 (4)	0.4692 (3)	0.0359 (6)
C4	0.7774 (3)	0.3969 (3)	0.2604 (3)	0.0345 (6)
O3	0.7554 (3)	0.8513 (3)	0.2813 (4)	0.0615 (8)
H3C	0.6936	0.8514	0.2251	0.092*
C9	0.8794 (3)	0.3737 (4)	0.3539 (5)	0.0491 (9)
H9	0.9079	0.2665	0.3728	0.059*
O1	0.4643 (3)	0.0409 (5)	0.3829 (3)	0.0810 (12)
H1B	0.4864	0.0058	0.3112	0.121*
C5	0.7337 (3)	0.5573 (3)	0.2338 (3)	0.0354 (6)
H5	0.6644	0.5739	0.1705	0.042*
C3	0.7094 (3)	0.2534 (4)	0.1859 (3)	0.0396 (7)
H3A	0.6824	0.2806	0.0842	0.048*
H3B	0.7581	0.1561	0.1906	0.048*
C6	0.7942 (3)	0.6920 (4)	0.3025 (4)	0.0420 (7)
C2	0.6411 (3)	0.1792 (4)	0.4121 (3)	0.0353 (6)
H2A	0.6614	0.2830	0.4636	0.042*
H2B	0.7073	0.1069	0.4309	0.042*
C7	0.8982 (4)	0.6685 (5)	0.3941 (5)	0.0542 (9)
H7	0.9395	0.7595	0.4375	0.065*
C8	0.9407 (3)	0.5093 (5)	0.4211 (5)	0.0598 (11)
H8	1.0102	0.4926	0.4841	0.072*
O4	0.4311 (2)	0.4024 (3)	0.0722 (2)	0.0387 (5)
N2	0.3782 (2)	0.2918 (3)	−0.3084 (3)	0.0320 (5)
H2C	0.4470	0.2960	−0.3224	0.038*
C10	0.4428 (3)	0.4038 (4)	−0.0589 (3)	0.0353 (6)
O6	0.2384 (3)	−0.3410 (3)	−0.3402 (4)	0.0595 (8)
H6A	0.2981	−0.3414	−0.3704	0.089*
C13	0.2093 (3)	0.1109 (3)	−0.3881 (3)	0.0356 (6)
O5	0.5208 (3)	0.4690 (5)	−0.1059 (3)	0.0742 (10)
H5A	0.4970	0.5018	−0.1891	0.111*
C14	0.2554 (3)	−0.0481 (4)	−0.3873 (3)	0.0355 (6)
H14	0.3250	−0.0643	−0.4151	0.043*
C11	0.3485 (3)	0.3195 (4)	−0.1654 (3)	0.0360 (6)
H11A	0.3313	0.2132	−0.1255	0.043*
H11B	0.2804	0.3878	−0.1777	0.043*
C18	0.1069 (3)	0.1349 (4)	−0.3470 (5)	0.0503 (8)
H18	0.0764	0.2415	−0.3476	0.060*
C12	0.2773 (3)	0.2555 (4)	−0.4279 (3)	0.0400 (7)
H12A	0.3035	0.2299	−0.5169	0.048*
H12B	0.2290	0.3534	−0.4454	0.048*
C15	0.1966 (3)	−0.1827 (4)	−0.3447 (4)	0.0392 (7)
C16	0.0943 (3)	−0.1573 (5)	−0.3026 (5)	0.0509 (9)
H16	0.0558	−0.2473	−0.2726	0.061*
C17	0.0483 (3)	−0.0004 (5)	−0.3043 (6)	0.0575 (10)
H17	−0.0215	0.0155	−0.2772	0.069*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O2	0.0484 (12)	0.0335 (11)	0.0343 (11)	−0.0017 (9)	0.0108 (9)	0.0037 (8)
N1	0.0403 (13)	0.0270 (11)	0.0340 (12)	−0.0019 (10)	0.0086 (10)	0.0040 (10)
C1	0.0409 (15)	0.0337 (14)	0.0340 (15)	−0.0043 (11)	0.0098 (12)	0.0009 (11)
C4	0.0388 (14)	0.0299 (13)	0.0394 (14)	−0.0002 (11)	0.0191 (12)	0.0034 (11)
O3	0.0655 (16)	0.0237 (10)	0.083 (2)	0.0011 (11)	−0.0151 (14)	−0.0043 (11)
C9	0.0442 (18)	0.0337 (15)	0.071 (2)	0.0074 (13)	0.0154 (17)	0.0101 (15)
O1	0.0679 (18)	0.133 (3)	0.0427 (14)	−0.054 (2)	0.0118 (13)	−0.0031 (17)
C5	0.0395 (15)	0.0279 (14)	0.0384 (15)	0.0006 (11)	0.0070 (12)	0.0048 (12)
C3	0.0541 (18)	0.0300 (14)	0.0400 (17)	−0.0011 (12)	0.0220 (14)	−0.0007 (11)
C6	0.0466 (17)	0.0289 (14)	0.0492 (18)	−0.0003 (12)	0.0064 (14)	0.0031 (13)
C2	0.0382 (14)	0.0379 (15)	0.0320 (13)	−0.0036 (12)	0.0120 (11)	−0.0017 (11)
C7	0.055 (2)	0.0395 (17)	0.063 (2)	−0.0074 (15)	−0.0017 (17)	0.0021 (16)
C8	0.0396 (17)	0.051 (2)	0.081 (3)	0.0002 (15)	−0.0062 (17)	0.0135 (19)
O4	0.0513 (13)	0.0331 (11)	0.0325 (10)	−0.0013 (9)	0.0099 (9)	−0.0041 (8)
N2	0.0355 (12)	0.0259 (10)	0.0353 (12)	−0.0016 (9)	0.0092 (10)	−0.0023 (9)
C10	0.0418 (15)	0.0323 (13)	0.0319 (14)	−0.0026 (11)	0.0077 (12)	−0.0033 (11)
O6	0.0686 (17)	0.0265 (10)	0.093 (2)	0.0015 (11)	0.0384 (16)	0.0071 (12)
C13	0.0411 (15)	0.0299 (14)	0.0325 (14)	−0.0031 (11)	−0.0009 (11)	−0.0027 (11)
O5	0.0715 (18)	0.109 (3)	0.0444 (15)	−0.0508 (19)	0.0164 (13)	−0.0151 (16)
C14	0.0383 (14)	0.0318 (14)	0.0376 (14)	0.0005 (11)	0.0106 (12)	−0.0050 (12)
C11	0.0416 (15)	0.0364 (14)	0.0301 (13)	−0.0045 (12)	0.0075 (11)	−0.0013 (11)
C18	0.0451 (18)	0.0396 (17)	0.065 (2)	0.0081 (15)	0.0079 (16)	−0.0067 (16)
C12	0.0567 (19)	0.0284 (13)	0.0324 (15)	−0.0041 (13)	0.0028 (14)	0.0005 (11)
C15	0.0428 (16)	0.0300 (14)	0.0451 (17)	−0.0035 (12)	0.0095 (13)	−0.0038 (12)
C16	0.053 (2)	0.0401 (17)	0.063 (2)	−0.0113 (15)	0.0201 (17)	−0.0053 (16)
C17	0.0388 (17)	0.052 (2)	0.085 (3)	−0.0011 (15)	0.0225 (17)	−0.0100 (19)

Geometric parameters (Å, º) top

O2—C1	1.268 (4)	O4—C10	1.266 (4)
N1—C2	1.479 (4)	N2—C11	1.472 (4)
N1—C3	1.501 (4)	N2—C12	1.507 (4)
N1—H1A	0.8600	N2—H2C	0.8600
C1—O1	1.217 (4)	C10—O5	1.226 (4)
C1—C2	1.514 (4)	C10—C11	1.512 (4)
C4—C9	1.369 (5)	O6—C15	1.362 (4)
C4—C5	1.394 (4)	O6—H6A	0.8200
C4—C3	1.501 (4)	C13—C18	1.370 (5)
O3—C6	1.362 (4)	C13—C14	1.390 (4)
O3—H3C	0.8200	C13—C12	1.507 (4)
C9—C8	1.392 (6)	O5—H5A	0.8200
C9—H9	0.9300	C14—C15	1.391 (4)
O1—H1B	0.8200	C14—H14	0.9300
C5—C6	1.387 (4)	C11—H11A	0.9700
C5—H5	0.9300	C11—H11B	0.9700
C3—H3A	0.9700	C18—C17	1.394 (6)
C3—H3B	0.9700	C18—H18	0.9300
C6—C7	1.380 (5)	C12—H12A	0.9700
C2—H2A	0.9700	C12—H12B	0.9700
C2—H2B	0.9700	C15—C16	1.376 (5)
C7—C8	1.381 (6)	C16—C17	1.373 (6)
C7—H7	0.9300	C16—H16	0.9300
C8—H8	0.9300	C17—H17	0.9300

C2—N1—C3	113.6 (2)	C11—N2—C12	113.9 (2)
C2—N1—H1A	123.2	C11—N2—H2C	123.1
C3—N1—H1A	123.2	C12—N2—H2C	123.1
O1—C1—O2	126.0 (3)	O5—C10—O4	126.3 (3)
O1—C1—C2	119.0 (3)	O5—C10—C11	118.5 (3)
O2—C1—C2	115.0 (3)	O4—C10—C11	115.2 (3)
C9—C4—C5	119.8 (3)	C15—O6—H6A	109.5
C9—C4—C3	121.8 (3)	C18—C13—C14	120.3 (3)
C5—C4—C3	118.4 (3)	C18—C13—C12	121.3 (3)
C6—O3—H3C	109.5	C14—C13—C12	118.4 (3)
C4—C9—C8	120.6 (3)	C10—O5—H5A	109.5
C4—C9—H9	119.7	C15—C14—C13	119.4 (3)
C8—C9—H9	119.7	C15—C14—H14	120.3
C1—O1—H1B	109.5	C13—C14—H14	120.3
C6—C5—C4	119.6 (3)	N2—C11—C10	112.7 (2)
C6—C5—H5	120.2	N2—C11—H11A	109.1
C4—C5—H5	120.2	C10—C11—H11A	109.1
N1—C3—C4	111.8 (2)	N2—C11—H11B	109.1
N1—C3—H3A	109.3	C10—C11—H11B	109.1
C4—C3—H3A	109.3	H11A—C11—H11B	107.8
N1—C3—H3B	109.3	C13—C18—C17	120.0 (3)
C4—C3—H3B	109.3	C13—C18—H18	120.0
H3A—C3—H3B	107.9	C17—C18—H18	120.0
O3—C6—C7	117.3 (3)	N2—C12—C13	111.0 (2)
O3—C6—C5	122.2 (3)	N2—C12—H12A	109.4
C7—C6—C5	120.5 (3)	C13—C12—H12A	109.4
N1—C2—C1	111.8 (2)	N2—C12—H12B	109.4
N1—C2—H2A	109.3	C13—C12—H12B	109.4
C1—C2—H2A	109.3	H12A—C12—H12B	108.0
N1—C2—H2B	109.3	O6—C15—C16	118.2 (3)
C1—C2—H2B	109.3	O6—C15—C14	122.0 (3)
H2A—C2—H2B	107.9	C16—C15—C14	119.8 (3)
C8—C7—C6	119.7 (3)	C17—C16—C15	120.7 (3)
C8—C7—H7	120.1	C17—C16—H16	119.6
C6—C7—H7	120.1	C15—C16—H16	119.6
C7—C8—C9	119.8 (3)	C16—C17—C18	119.7 (3)
C7—C8—H8	120.1	C16—C17—H17	120.2
C9—C8—H8	120.1	C18—C17—H17	120.2

C5—C4—C9—C8	−1.0 (5)	C18—C13—C14—C15	0.1 (5)
C3—C4—C9—C8	179.8 (4)	C12—C13—C14—C15	177.2 (3)
C9—C4—C5—C6	0.1 (5)	C12—N2—C11—C10	−163.2 (2)
C3—C4—C5—C6	179.3 (3)	O5—C10—C11—N2	14.3 (5)
C2—N1—C3—C4	−55.5 (3)	O4—C10—C11—N2	−167.2 (3)
C9—C4—C3—N1	103.7 (4)	C14—C13—C18—C17	−0.1 (5)
C5—C4—C3—N1	−75.5 (3)	C12—C13—C18—C17	−177.1 (4)
C4—C5—C6—O3	−179.7 (3)	C11—N2—C12—C13	−54.6 (3)
C4—C5—C6—C7	1.4 (5)	C18—C13—C12—N2	105.2 (3)
C3—N1—C2—C1	−165.6 (2)	C14—C13—C12—N2	−71.9 (4)
O1—C1—C2—N1	13.6 (5)	C13—C14—C15—O6	−179.2 (3)
O2—C1—C2—N1	−167.4 (3)	C13—C14—C15—C16	−0.6 (5)
O3—C6—C7—C8	179.0 (4)	O6—C15—C16—C17	179.7 (4)
C5—C6—C7—C8	−2.0 (6)	C14—C15—C16—C17	1.1 (6)
C6—C7—C8—C9	1.1 (7)	C15—C16—C17—C18	−1.0 (6)
C4—C9—C8—C7	0.4 (7)	C13—C18—C17—C16	0.5 (6)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4	0.86	2.25	2.891 (3)	132
O3—H3C···O2ⁱ	0.82	1.84	2.639 (4)	166
N2—H2C···O2ⁱⁱ	0.86	2.28	2.910 (3)	130
O6—H6A···O4ⁱⁱⁱ	0.82	1.85	2.646 (4)	165

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

Experimental details

Crystal data
Chemical formula	C₉H₁₁NO₃
M_r	181.19
Crystal system, space group	Monoclinic, Pc
Temperature (K)	296
a, b, c (Å)	11.9779 (3), 8.0267 (2), 9.3835 (2)
β (°)	101.391 (2)
V (Å³)	884.39 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.23 × 0.16 × 0.12

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2007)
T_min, T_max	0.980, 0.988
No. of measured, independent and observed [I > 2σ(I)] reflections	7436, 1999, 1815
R_int	0.022
(sin θ/λ)_max (Å⁻¹)	0.646

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.043, 0.134, 1.07
No. of reflections	1999
No. of parameters	235
No. of restraints	2
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.40, −0.32

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4	0.86	2.25	2.891 (3)	132
O3—H3C···O2ⁱ	0.82	1.84	2.639 (4)	166
N2—H2C···O2ⁱⁱ	0.86	2.28	2.910 (3)	130
O6—H6A···O4ⁱⁱⁱ	0.82	1.85	2.646 (4)	165

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

Acknowledgements

The authors are grateful for financial support from the Doctoral Foundation of Henan Polytechnic University (B2009–65 648359 and B2009–70 648364).

References

Bruker (2007). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA . Google Scholar
Jia, L., Jiang, P., Xu, J., Hao, Z.-Y., Xu, X.-M., Chen, L.-H., Wu, J.-C., Tang, N., Wang, Q. & Vittal, J. J. (2010). Inorg. Chim. Acta, 363, 855–865. CrossRef CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar