(Z)-Ethyl 2,4-diphenyl-3-(propyl­amino)­but-2-enoate

Jin, H.; Li, P.; Liu, B.; Cheng, X.

doi:10.1107/S160053680804395X

organic compounds

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ISSN: 2056-9890

Volume 65| Part 2| February 2009| Page o236

doi:10.1107/S160053680804395X

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(Z)-Ethyl 2,4-diphenyl-3-(propylamino)but-2-enoate

Huimin Jin,^a ^* Peifan Li,^a Bin Liu ^a and Xiaoqing Cheng ^a

^aDepartment of Pharmaceuticals, Tianjin Medical College, Tianjin 300222, People's Republic of China
^*Correspondence e-mail: huiminjin@yahoo.cn

(Received 23 December 2008; accepted 25 December 2008; online 8 January 2009)

The title compound, C₂₁H₂₅NO₂, adopts a Z conformation about the C=C double bond. The molecular structure is stabilized by an intramolecular N—H⋯O hydrogen bond and the dihedral angle between the aromatic ring planes is 76.04 (12)°. The atoms of the ethyl substituent are disordered over two sets of sites in a 0.60 (2):0.40 (2) ratio.

Related literature

For the synthesis, see: Du et al. (2006 ). For background, see: Xue et al. (2007 ).

Experimental

Crystal data

C₂₁H₂₅NO₂
M_r = 323.42
Monoclinic, P 2₁ /n
a = 12.186 (2) Å
b = 8.4771 (17) Å
c = 19.080 (4) Å
β = 106.33 (3)°
V = 1891.4 (7) Å³
Z = 4
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 293 (2) K
0.28 × 0.22 × 0.18 mm

Data collection

Rigaku Saturn diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005 ) T_min = 0.980, T_max = 0.987
12325 measured reflections
3323 independent reflections
2290 reflections with I > 2σ(I)
R_int = 0.034

Refinement

R[F² > 2σ(F²)] = 0.060
wR(F²) = 0.198
S = 1.06
3323 reflections
232 parameters
5 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.24 e Å⁻³
Δρ_min = −0.19 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O2	0.905 (16)	1.925 (17)	2.653 (3)	136.3 (14)

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear; data reduction: CrystalClear; 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 global, I. DOI: 10.1107/S160053680804395X/hb2886sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680804395X/hb2886Isup2.hkl

checkCIF report

Comment top

Enamine compounds have been considered to be potential antibacterial agents (Xue et al., 2007) and found important application in the synthesis of N-containint heterocylcles (Du et al., 2006). To further study the structure and activity relationship, we determine the crystal structure of the title compound, (I).

In the molecular structure (Fig. 1), the torsion angles of N1—C11—C7—C6 and C8—C7—C11—C12 are -177.32 (17) and -175.14 (16)°, respectively. Furthermore, the distances C7—C11 and C11—N1 are 1.381 (3), 1.348 (3)Å, respectively. Both of these features confirm the enamine structure formation. The two phenyl rings constructed an angle of 76.04 (12)°. The molecule adopts a Z-conformation, being stabilised by an intramolecular N—H···O hydrogen bond (Table 1).

Related literature top

For the synthesis, see: Du et al. (2006). For background, see: Xue et al. (2007).

Experimental top

The title compound was prepared according to the method of the literature (Du, et al., 2006). Colourless blocks of (I) were grown from a mixture of ethyl actate and petroleum ether.

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear (Rigaku/MSC, 2005); data reduction: CrystalClear (Rigaku/MSC, 2005); 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 molecular structure of (I) with 50% probability displacement ellipsoids. The dashed line indicates the intramolecular N—H···O hydrogen bond.

(Z)-Ethyl 2,4-diphenyl-3-(propylamino)but-2-enoate top

Crystal data top

C₂₁H₂₅NO₂	F(000) = 696
M_r = 323.42	D_x = 1.136 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 4099 reflections
a = 12.186 (2) Å	θ = 2.2–27.1°
b = 8.4771 (17) Å	µ = 0.07 mm⁻¹
c = 19.080 (4) Å	T = 293 K
β = 106.33 (3)°	Block, colourless
V = 1891.4 (7) Å³	0.28 × 0.22 × 0.18 mm
Z = 4

Data collection top

Rigaku Saturn diffractometer	3323 independent reflections
Radiation source: rotating anode	2290 reflections with I > 2σ(I)
Confocal monochromator	R_int = 0.034
Detector resolution: 7.31 pixels mm^-1	θ_max = 25.0°, θ_min = 2.2°
ω scans	h = −14→14
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005)	k = −9→10
T_min = 0.980, T_max = 0.987	l = −21→22
12325 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.060	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.198	w = 1/[σ²(F_o²) + (0.1207P)² + 0.019P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max = 0.001
3323 reflections	Δρ_max = 0.24 e Å⁻³
232 parameters	Δρ_min = −0.19 e Å⁻³
5 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.079 (13)

Crystal data top

C₂₁H₂₅NO₂	V = 1891.4 (7) Å³
M_r = 323.42	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 12.186 (2) Å	µ = 0.07 mm⁻¹
b = 8.4771 (17) Å	T = 293 K
c = 19.080 (4) Å	0.28 × 0.22 × 0.18 mm
β = 106.33 (3)°

Data collection top

Rigaku Saturn diffractometer	3323 independent reflections
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005)	2290 reflections with I > 2σ(I)
T_min = 0.980, T_max = 0.987	R_int = 0.034
12325 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.060	5 restraints
wR(F²) = 0.198	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	Δρ_max = 0.24 e Å⁻³
3323 reflections	Δρ_min = −0.19 e Å⁻³
232 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	Occ. (<1)
O1	0.98880 (16)	0.7415 (2)	0.24987 (10)	0.0936 (6)
O2	1.07264 (14)	0.97745 (19)	0.24972 (8)	0.0791 (5)
N1	0.95170 (17)	1.1941 (2)	0.16036 (11)	0.0710 (6)
C1	0.7770 (2)	0.7362 (3)	0.07667 (13)	0.0723 (7)
H1	0.8213	0.7655	0.0463	0.087*
C2	0.6935 (2)	0.6239 (3)	0.05278 (16)	0.0864 (8)
H2A	0.6812	0.5794	0.0067	0.104*
C3	0.6286 (2)	0.5778 (3)	0.09719 (18)	0.0906 (8)
H3A	0.5719	0.5018	0.0814	0.109*
C4	0.6473 (2)	0.6434 (4)	0.16427 (18)	0.0977 (9)
H4A	0.6038	0.6115	0.1947	0.117*
C5	0.7302 (2)	0.7568 (3)	0.18764 (14)	0.0829 (8)
H5A	0.7415	0.8007	0.2338	0.099*
C6	0.79728 (17)	0.8072 (2)	0.14437 (11)	0.0591 (6)
C7	0.88662 (17)	0.9301 (2)	0.16911 (10)	0.0572 (6)
C8	0.99038 (19)	0.8903 (3)	0.22513 (12)	0.0654 (6)
C9	1.0852 (3)	0.6899 (4)	0.30878 (18)	0.1159 (11)	0.60 (2)
H9A	1.1075	0.5855	0.2971	0.139*	0.60 (2)
H9B	1.1489	0.7602	0.3112	0.139*	0.60 (2)
C10	1.0665 (11)	0.684 (2)	0.3778 (4)	0.133 (4)	0.60 (2)
H10A	1.1353	0.6512	0.4133	0.199*	0.60 (2)
H10B	1.0063	0.6106	0.3770	0.199*	0.60 (2)
H10C	1.0450	0.7871	0.3904	0.199*	0.60 (2)
C9'	1.0852 (3)	0.6899 (4)	0.30878 (18)	0.1159 (11)	0.40 (2)
H9'A	1.1328	0.7787	0.3306	0.139*	0.40 (2)
H9'B	1.1314	0.6146	0.2913	0.139*	0.40 (2)
C10'	1.0339 (12)	0.616 (2)	0.3618 (8)	0.111 (4)	0.40 (2)
H10D	1.0935	0.5788	0.4030	0.166*	0.40 (2)
H10E	0.9871	0.5285	0.3392	0.166*	0.40 (2)
H10F	0.9879	0.6918	0.3779	0.166*	0.40 (2)
C11	0.87065 (17)	1.0815 (2)	0.14123 (11)	0.0588 (6)
C12	0.75990 (17)	1.1280 (2)	0.08755 (11)	0.0618 (6)
H12A	0.7336	1.2250	0.1045	0.074*
H12B	0.7036	1.0471	0.0876	0.074*
C13	0.76341 (16)	1.1525 (2)	0.00975 (11)	0.0565 (5)
C14	0.6757 (2)	1.2334 (3)	−0.03842 (14)	0.0745 (7)
H14A	0.6150	1.2716	−0.0228	0.089*
C15	0.6773 (3)	1.2584 (3)	−0.11014 (15)	0.0918 (8)
H15A	0.6185	1.3148	−0.1419	0.110*
C16	0.7651 (2)	1.2003 (3)	−0.13433 (14)	0.0849 (8)
H16A	0.7663	1.2175	−0.1822	0.102*
C17	0.8495 (2)	1.1182 (3)	−0.08805 (14)	0.0803 (7)
H17A	0.9085	1.0766	−0.1045	0.096*
C18	0.84946 (18)	1.0953 (3)	−0.01624 (12)	0.0706 (6)
H18A	0.9093	1.0397	0.0151	0.085*
C19	0.9397 (2)	1.3609 (3)	0.14108 (16)	0.0837 (8)
H19A	0.9085	1.4167	0.1755	0.100*
H19B	0.8867	1.3728	0.0928	0.100*
C20	1.0546 (3)	1.4324 (3)	0.14196 (19)	0.1120 (11)
H20A	1.0446	1.5452	0.1344	0.134*
H20B	1.1070	1.4167	0.1902	0.134*
C21	1.1081 (3)	1.3697 (4)	0.0878 (3)	0.1381 (14)
H21A	1.1817	1.4177	0.0946	0.207*
H21B	1.0605	1.3929	0.0396	0.207*
H21C	1.1169	1.2576	0.0937	0.207*
H1A	1.0180 (11)	1.163 (2)	0.1924 (9)	0.065 (6)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0861 (12)	0.0898 (12)	0.0851 (13)	0.0094 (9)	−0.0083 (10)	0.0275 (9)
O2	0.0732 (11)	0.0914 (11)	0.0625 (10)	0.0011 (8)	0.0026 (8)	−0.0069 (8)
N1	0.0710 (13)	0.0671 (11)	0.0688 (13)	−0.0032 (9)	0.0099 (11)	0.0003 (9)
C1	0.0817 (16)	0.0716 (13)	0.0667 (15)	−0.0068 (11)	0.0257 (13)	−0.0040 (11)
C2	0.0884 (17)	0.0779 (15)	0.0873 (18)	−0.0122 (13)	0.0156 (15)	−0.0051 (13)
C3	0.0755 (16)	0.0790 (16)	0.107 (2)	−0.0092 (12)	0.0090 (16)	0.0195 (15)
C4	0.0823 (18)	0.119 (2)	0.094 (2)	−0.0134 (16)	0.0297 (17)	0.0302 (18)
C5	0.0798 (17)	0.1103 (19)	0.0628 (15)	−0.0056 (14)	0.0270 (14)	0.0115 (13)
C6	0.0591 (12)	0.0645 (12)	0.0522 (12)	0.0079 (9)	0.0132 (10)	0.0094 (10)
C7	0.0629 (12)	0.0659 (12)	0.0428 (11)	0.0084 (9)	0.0148 (9)	0.0027 (9)
C8	0.0712 (14)	0.0745 (13)	0.0487 (12)	0.0090 (11)	0.0138 (11)	−0.0020 (11)
C9	0.096 (2)	0.133 (2)	0.094 (2)	0.0225 (18)	−0.0132 (18)	0.040 (2)
C10	0.102 (6)	0.194 (10)	0.081 (5)	0.043 (6)	−0.010 (4)	−0.022 (5)
C9'	0.096 (2)	0.133 (2)	0.094 (2)	0.0225 (18)	−0.0132 (18)	0.040 (2)
C10'	0.119 (8)	0.129 (9)	0.060 (6)	−0.016 (7)	−0.015 (5)	0.041 (6)
C11	0.0645 (12)	0.0669 (12)	0.0475 (11)	0.0055 (9)	0.0197 (10)	−0.0032 (9)
C12	0.0585 (12)	0.0668 (12)	0.0617 (13)	0.0101 (9)	0.0196 (10)	0.0044 (10)
C13	0.0568 (12)	0.0509 (10)	0.0576 (12)	−0.0005 (8)	0.0092 (10)	0.0023 (9)
C14	0.0717 (15)	0.0751 (14)	0.0690 (16)	0.0136 (11)	0.0071 (12)	0.0039 (12)
C15	0.095 (2)	0.0952 (18)	0.0692 (17)	0.0136 (14)	−0.0033 (15)	0.0173 (14)
C16	0.0953 (19)	0.0984 (18)	0.0556 (14)	−0.0162 (15)	0.0123 (14)	0.0129 (13)
C17	0.0747 (16)	0.1049 (18)	0.0626 (15)	0.0008 (13)	0.0213 (13)	0.0083 (13)
C18	0.0618 (13)	0.0874 (15)	0.0608 (14)	0.0117 (11)	0.0144 (11)	0.0121 (11)
C19	0.0904 (17)	0.0636 (14)	0.099 (2)	−0.0011 (12)	0.0290 (15)	−0.0085 (13)
C20	0.129 (3)	0.0726 (16)	0.138 (3)	−0.0143 (16)	0.044 (2)	−0.0030 (17)
C21	0.136 (3)	0.100 (2)	0.205 (4)	−0.006 (2)	0.092 (3)	−0.004 (2)

Geometric parameters (Å, º) top

O1—C8	1.349 (3)	C10'—H10E	0.9600
O1—C9	1.446 (3)	C10'—H10F	0.9600
O2—C8	1.227 (3)	C11—C12	1.499 (3)
N1—C11	1.348 (3)	C12—C13	1.511 (3)
N1—C19	1.458 (3)	C12—H12A	0.9700
N1—H1A	0.905 (10)	C12—H12B	0.9700
C1—C2	1.374 (3)	C13—C18	1.369 (3)
C1—C6	1.383 (3)	C13—C14	1.381 (3)
C1—H1	0.9300	C14—C15	1.390 (4)
C2—C3	1.369 (4)	C14—H14A	0.9300
C2—H2A	0.9300	C15—C16	1.370 (4)
C3—C4	1.355 (4)	C15—H15A	0.9300
C3—H3A	0.9300	C16—C17	1.346 (3)
C4—C5	1.375 (4)	C16—H16A	0.9300
C4—H4A	0.9300	C17—C18	1.384 (3)
C5—C6	1.383 (3)	C17—H17A	0.9300
C5—H5A	0.9300	C18—H18A	0.9300
C6—C7	1.485 (3)	C19—C20	1.522 (3)
C7—C11	1.381 (3)	C19—H19A	0.9700
C7—C8	1.448 (3)	C19—H19B	0.9700
C9—C10	1.399 (7)	C20—C21	1.467 (4)
C9—H9A	0.9700	C20—H20A	0.9700
C9—H9B	0.9700	C20—H20B	0.9700
C10—H10A	0.9600	C21—H21A	0.9600
C10—H10B	0.9600	C21—H21B	0.9600
C10—H10C	0.9600	C21—H21C	0.9600
C10'—H10D	0.9600

C8—O1—C9	117.8 (2)	N1—C11—C12	116.66 (18)
C11—N1—C19	127.2 (2)	C7—C11—C12	120.63 (19)
C11—N1—H1A	114.9 (13)	C11—C12—C13	116.00 (16)
C19—N1—H1A	117.5 (13)	C11—C12—H12A	108.3
C2—C1—C6	122.2 (2)	C13—C12—H12A	108.3
C2—C1—H1	118.9	C11—C12—H12B	108.3
C6—C1—H1	118.9	C13—C12—H12B	108.3
C3—C2—C1	119.7 (3)	H12A—C12—H12B	107.4
C3—C2—H2A	120.2	C18—C13—C14	117.6 (2)
C1—C2—H2A	120.2	C18—C13—C12	122.92 (19)
C4—C3—C2	119.6 (3)	C14—C13—C12	119.44 (18)
C4—C3—H3A	120.2	C13—C14—C15	120.5 (2)
C2—C3—H3A	120.2	C13—C14—H14A	119.7
C3—C4—C5	120.4 (2)	C15—C14—H14A	119.7
C3—C4—H4A	119.8	C16—C15—C14	120.4 (2)
C5—C4—H4A	119.8	C16—C15—H15A	119.8
C4—C5—C6	121.8 (2)	C14—C15—H15A	119.8
C4—C5—H5A	119.1	C17—C16—C15	119.3 (2)
C6—C5—H5A	119.1	C17—C16—H16A	120.3
C1—C6—C5	116.3 (2)	C15—C16—H16A	120.3
C1—C6—C7	121.66 (17)	C16—C17—C18	120.6 (2)
C5—C6—C7	122.1 (2)	C16—C17—H17A	119.7
C11—C7—C8	120.0 (2)	C18—C17—H17A	119.7
C11—C7—C6	121.21 (19)	C13—C18—C17	121.5 (2)
C8—C7—C6	118.74 (18)	C13—C18—H18A	119.2
O2—C8—O1	121.3 (2)	C17—C18—H18A	119.2
O2—C8—C7	126.3 (2)	N1—C19—C20	110.9 (2)
O1—C8—C7	112.4 (2)	N1—C19—H19A	109.5
C10—C9—O1	115.5 (5)	C20—C19—H19A	109.5
C10—C9—H9A	108.4	N1—C19—H19B	109.5
O1—C9—H9A	108.4	C20—C19—H19B	109.5
C10—C9—H9B	108.4	H19A—C19—H19B	108.0
O1—C9—H9B	108.4	C21—C20—C19	115.9 (3)
H9A—C9—H9B	107.5	C21—C20—H20A	108.3
C9—C10—H10A	109.5	C19—C20—H20A	108.3
C9—C10—H10B	109.5	C21—C20—H20B	108.3
H10A—C10—H10B	109.5	C19—C20—H20B	108.3
C9—C10—H10C	109.5	H20A—C20—H20B	107.4
H10A—C10—H10C	109.5	C20—C21—H21A	109.5
H10B—C10—H10C	109.5	C20—C21—H21B	109.5
H10D—C10'—H10E	109.5	H21A—C21—H21B	109.5
H10D—C10'—H10F	109.5	C20—C21—H21C	109.5
H10E—C10'—H10F	109.5	H21A—C21—H21C	109.5
N1—C11—C7	122.7 (2)	H21B—C21—H21C	109.5

C6—C1—C2—C3	−0.9 (4)	C19—N1—C11—C12	7.4 (3)
C1—C2—C3—C4	0.0 (4)	C8—C7—C11—N1	4.6 (3)
C2—C3—C4—C5	0.6 (4)	C6—C7—C11—N1	−177.32 (17)
C3—C4—C5—C6	−0.3 (4)	C8—C7—C11—C12	−175.14 (16)
C2—C1—C6—C5	1.2 (3)	C6—C7—C11—C12	2.9 (3)
C2—C1—C6—C7	−179.1 (2)	N1—C11—C12—C13	71.9 (2)
C4—C5—C6—C1	−0.5 (4)	C7—C11—C12—C13	−108.3 (2)
C4—C5—C6—C7	179.7 (2)	C11—C12—C13—C18	17.9 (3)
C1—C6—C7—C11	74.3 (3)	C11—C12—C13—C14	−163.29 (19)
C5—C6—C7—C11	−105.9 (2)	C18—C13—C14—C15	−1.5 (3)
C1—C6—C7—C8	−107.6 (2)	C12—C13—C14—C15	179.6 (2)
C5—C6—C7—C8	72.1 (3)	C13—C14—C15—C16	1.2 (4)
C9—O1—C8—O2	2.7 (3)	C14—C15—C16—C17	0.3 (4)
C9—O1—C8—C7	−176.8 (2)	C15—C16—C17—C18	−1.4 (4)
C11—C7—C8—O2	−3.9 (3)	C14—C13—C18—C17	0.4 (3)
C6—C7—C8—O2	178.02 (18)	C12—C13—C18—C17	179.3 (2)
C11—C7—C8—O1	175.63 (17)	C16—C17—C18—C13	1.1 (4)
C6—C7—C8—O1	−2.5 (2)	C11—N1—C19—C20	−154.4 (2)
C8—O1—C9—C10	103.2 (10)	N1—C19—C20—C21	64.4 (4)
C19—N1—C11—C7	−172.39 (19)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O2	0.91 (2)	1.93 (2)	2.653 (3)	136 (1)

Experimental details

Crystal data
Chemical formula	C₂₁H₂₅NO₂
M_r	323.42
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	293
a, b, c (Å)	12.186 (2), 8.4771 (17), 19.080 (4)
β (°)	106.33 (3)
V (Å³)	1891.4 (7)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.07
Crystal size (mm)	0.28 × 0.22 × 0.18

Data collection
Diffractometer	Rigaku Saturn diffractometer
Absorption correction	Multi-scan (CrystalClear; Rigaku/MSC, 2005)
T_min, T_max	0.980, 0.987
No. of measured, independent and observed [I > 2σ(I)] reflections	12325, 3323, 2290
R_int	0.034
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.060, 0.198, 1.06
No. of reflections	3323
No. of parameters	232
No. of restraints	5
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.24, −0.19

Computer programs: CrystalClear (Rigaku/MSC, 2005), 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···O2	0.905 (16)	1.925 (17)	2.653 (3)	136.3 (14)

Acknowledgements

We thank the Technology Fund of Tianjin Bureau of Public Health (grant No. 04KY36) for financial support.

References

Du, Y., Liu, R., Linn, G. & Zhao, K. (2006). Org. Lett. 8, 5919–5922. Web of Science CSD CrossRef PubMed CAS Google Scholar
Rigaku/MSC (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Xue, J. Y., Xiao, Z. P., Shi, L., Tan, S. H., Li, H. Q. & Zhu, H. L. (2007). Aust. J. Chem. 60, 957–962. Web of Science CrossRef CAS Google Scholar