1,3-Bis(4-meth­oxy­benz­yl)-6-methyl­pyrimidine-2,4(1H,3H)-dione

Li, G.-C.; Zhang, L.-K.; Ju, Z.-Y.; Yang, F.-L.

doi:10.1107/S1600536810024815

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 66| Part 7| July 2010| Page o1858

doi:10.1107/S1600536810024815

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1,3-Bis(4-methoxybenzyl)-6-methylpyrimidine-2,4(1H,3H)-dione

Gong-Chun Li,^a Li-Ke Zhang,^a Zhi-Yu Ju ^a and Feng-Ling Yang ^a ^*

^aCollege of Chemistry and Chemical Engineering, Xuchang University, Xuchang, Henan Province 461000, People's Republic of China
^*Correspondence e-mail: actaeli@gmail.com

(Received 10 June 2010; accepted 24 June 2010; online 30 June 2010)

The title compound, C₂₁H₂₂N₂O₄, was prepared by reaction of 6-methylpyrimidine-2,4(1H,3H)-dione and 1-chloromethyl-4-methoxybenzene. In the title molecule, the central pyrimidine ring forms dihedral angles of 62.16 (4) and 69.77 (3)° with the two benzene rings. In the crystal, weak intermolecular C—H⋯O hydrogen bonds link the molecules into chains.

Related literature

For the applications of pyrimidine derivatives as pesticides and pharmaceutical agents, see: Condon et al. (1993 ); as agrochemicals, see: Maeno et al. (1990 ); as antiviral agents, see: Gilchrist (1997 ); as herbicides, see: Selby et al. (2002 ); Zhu et al. (2007 ). For a related structure, see: Yang & Li (2006 ).

Experimental

Crystal data

C₂₁H₂₂N₂O₄
M_r = 366.41
Monoclinic, P 2₁ /n
a = 8.4133 (9) Å
b = 9.929 (1) Å
c = 21.407 (3) Å
β = 91.614 (4)°
V = 1787.5 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 113 K
0.26 × 0.24 × 0.22 mm

Data collection

Rigaku Saturn724 CCD diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2009 ) T_min = 0.976, T_max = 0.979
17394 measured reflections
4250 independent reflections
3035 reflections with I > 2σ(I)
R_int = 0.037

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.096
S = 0.98
4250 reflections
247 parameters
H-atom parameters constrained
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.16 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C20—H20⋯O3ⁱ	0.95	2.51	3.3627 (14)	150
Symmetry code: (i) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: CrystalClear (Rigaku/MSC, 2009); 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: CrystalStructure (Rigaku/MSC, 2009); software used to prepare material for publication: CrystalStructure.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810024815/pk2250sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810024815/pk2250Isup2.hkl

checkCIF report

Comment top

Pyrimidine derivatives are very important molecules in biology and have many applications in the areas of pesticide and pharmaceutical agents (Condon et al., 1993). For example, imazosulfuron, ethirmol and mepanipyrim have been commercialized as agrochemicals (Maeno et al., 1990). Pyrimidine derivatives have also been developed as antiviral agents, such as AZT, which is the most widely used anti-AIDS drug (Gilchrist, 1997). Recently, a new series of highly active herbicides of substituted pyrimidines were reported (Selby et al., 2002); (Zhu et al., 2007), and we have previously reported a related structure (Yang & Li 2006). As part of our goal to discover further biologically active pyrimidine compounds, the title compound was synthesized and its crystal structure determined (Fig. 1).

In the title molecule, the central pyrimidine ring forms dihedral angles of 62.16 (4) and 69.77 (3)° with the two benzene rings. In the crystal, weak intermolecular C—H···O hydrogen bonds link molecules.

Related literature top

For the applications of pyrimidine derivatives as pesticides and pharmaceutical agents, see: Condon et al. (1993); as agrochemicals, see: Maeno et al. (1990); as antiviral agents, see: Gilchrist (1997); as herbicides, see: Selby et al. (2002); Zhu et al. (2007). For a related structure, see: Yang & Li (2006).

Experimental top

6-methylpyrimidine-2,4(1H,3H)-dione (0.63 g, 5 mmol) and anhydrous potassium carbonate (0.84 g, 6 mmol) were mixed in dimethylformamide (20 ml). A solution of 1-(chloromethyl)-4-methoxybenzene (0.79 g, 5 mmol) in acetone (10 ml) was then added dropwise, with stirring at room temperature, and the mixture was stirred for another 10 h and then refluxed for 4 h. The solvent was evaporated in vacuo and the residue was washed with water. The resulting white precipitate was recrystallized from ethanol and single crystals were obtained by slow evaporation.

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2009); cell refinement: CrystalClear (Rigaku/MSC, 2009); data reduction: CrystalClear (Rigaku/MSC, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalStructure (Rigaku/MSC, 2009); software used to prepare material for publication: CrystalStructure (Rigaku/MSC, 2009).

Figures top

	Fig. 1. The asymmetric unit of the title compound, with displacement ellipsoids drawn at the 30% probability level.
	Fig. 2. A packing diagram of the title compound viewed down the a axis. Intermolecular hydrogen bonds are shown as dashed lines.

1,3-Bis(4-methoxybenzyl)-6-methylpyrimidine-2,4(1H,3H)-dione top

Crystal data top

C₂₁H₂₂N₂O₄	F(000) = 776
M_r = 366.41	D_x = 1.361 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71075 Å
Hall symbol: -P 2yn	Cell parameters from 5810 reflections
a = 8.4133 (9) Å	θ = 1.9–28.0°
b = 9.929 (1) Å	µ = 0.10 mm⁻¹
c = 21.407 (3) Å	T = 113 K
β = 91.614 (4)°	Prism, colorless
V = 1787.5 (3) Å³	0.26 × 0.24 × 0.22 mm
Z = 4

Data collection top

Rigaku Saturn724 CCD diffractometer	4250 independent reflections
Radiation source: fine-focus sealed tube	3035 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.037
Detector resolution: 14.222 pixels mm^-1	θ_max = 27.9°, θ_min = 1.9°
ω scans	h = −9→11
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2009)	k = −12→13
T_min = 0.976, T_max = 0.979	l = −28→28
17394 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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.096	H-atom parameters constrained
S = 0.98	w = 1/[σ²(F_o²) + (0.0556P)²] where P = (F_o² + 2F_c²)/3
4250 reflections	(Δ/σ)_max = 0.001
247 parameters	Δρ_max = 0.29 e Å⁻³
0 restraints	Δρ_min = −0.16 e Å⁻³

Crystal data top

C₂₁H₂₂N₂O₄	V = 1787.5 (3) Å³
M_r = 366.41	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 8.4133 (9) Å	µ = 0.10 mm⁻¹
b = 9.929 (1) Å	T = 113 K
c = 21.407 (3) Å	0.26 × 0.24 × 0.22 mm
β = 91.614 (4)°

Data collection top

Rigaku Saturn724 CCD diffractometer	4250 independent reflections
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2009)	3035 reflections with I > 2σ(I)
T_min = 0.976, T_max = 0.979	R_int = 0.037
17394 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	0 restraints
wR(F²) = 0.096	H-atom parameters constrained
S = 0.98	Δρ_max = 0.29 e Å⁻³
4250 reflections	Δρ_min = −0.16 e Å⁻³
247 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
O1	0.77270 (10)	−0.03179 (8)	0.39409 (4)	0.0326 (2)
O2	1.05849 (10)	0.35414 (9)	0.42566 (4)	0.0349 (2)
O3	0.38155 (9)	0.43800 (8)	0.57937 (3)	0.0258 (2)
O4	1.17640 (10)	−0.48075 (8)	0.20574 (4)	0.0286 (2)
N1	0.91553 (10)	0.16121 (9)	0.41019 (4)	0.0235 (2)
N2	0.87518 (10)	0.07201 (9)	0.30901 (4)	0.0231 (2)
C1	0.84910 (13)	0.06125 (12)	0.37267 (5)	0.0244 (3)
C2	1.00559 (13)	0.27014 (12)	0.38848 (5)	0.0257 (3)
C3	1.02826 (13)	0.27076 (12)	0.32258 (5)	0.0257 (3)
H3	1.0893	0.3408	0.3049	0.031*
C4	0.96571 (13)	0.17502 (11)	0.28489 (5)	0.0234 (2)
C5	0.99072 (15)	0.17657 (13)	0.21620 (5)	0.0304 (3)
H5A	1.0646	0.2492	0.2061	0.037*
H5B	0.8888	0.1915	0.1940	0.037*
H5C	1.0353	0.0900	0.2034	0.037*
C6	0.89544 (14)	0.14901 (13)	0.47867 (5)	0.0275 (3)
H6A	0.9940	0.1808	0.5003	0.033*
H6B	0.8820	0.0526	0.4891	0.033*
C7	0.75633 (13)	0.22666 (12)	0.50352 (5)	0.0229 (3)
C8	0.77921 (13)	0.34760 (12)	0.53566 (5)	0.0244 (3)
H8	0.8833	0.3838	0.5406	0.029*
C9	0.65212 (13)	0.41528 (12)	0.56044 (5)	0.0240 (3)
H9	0.6692	0.4972	0.5825	0.029*
C10	0.49895 (13)	0.36351 (11)	0.55308 (5)	0.0213 (2)
C11	0.47377 (14)	0.24358 (12)	0.52095 (5)	0.0250 (3)
H11	0.3694	0.2080	0.5156	0.030*
C12	0.60341 (13)	0.17605 (12)	0.49672 (5)	0.0248 (3)
H12	0.5866	0.0935	0.4751	0.030*
C13	0.22263 (13)	0.38888 (13)	0.57144 (6)	0.0292 (3)
H13A	0.1932	0.3867	0.5268	0.035*
H13B	0.1497	0.4485	0.5933	0.035*
H13C	0.2160	0.2978	0.5888	0.035*
C14	0.79638 (13)	−0.02957 (12)	0.26809 (6)	0.0263 (3)
H14A	0.7576	0.0153	0.2293	0.032*
H14B	0.7027	−0.0656	0.2895	0.032*
C15	0.90264 (13)	−0.14602 (11)	0.25073 (5)	0.0224 (2)
C16	0.97928 (13)	−0.22551 (12)	0.29611 (5)	0.0236 (3)
H16	0.9686	−0.2036	0.3390	0.028*
C17	1.06997 (13)	−0.33503 (12)	0.28015 (5)	0.0243 (3)
H17	1.1212	−0.3876	0.3118	0.029*
C18	1.08652 (13)	−0.36866 (11)	0.21741 (5)	0.0224 (2)
C19	1.01334 (13)	−0.28976 (12)	0.17146 (5)	0.0251 (3)
H19	1.0255	−0.3107	0.1286	0.030*
C20	0.92206 (13)	−0.17982 (12)	0.18864 (5)	0.0249 (3)
H20	0.8717	−0.1265	0.1570	0.030*
C21	1.18686 (15)	−0.52057 (13)	0.14183 (5)	0.0324 (3)
H21A	1.0798	−0.5359	0.1241	0.039*
H21B	1.2489	−0.6038	0.1393	0.039*
H21C	1.2391	−0.4493	0.1183	0.039*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0372 (5)	0.0225 (5)	0.0387 (5)	−0.0028 (4)	0.0125 (4)	−0.0013 (4)
O2	0.0361 (5)	0.0325 (5)	0.0360 (5)	−0.0066 (4)	−0.0008 (4)	−0.0107 (4)
O3	0.0232 (4)	0.0286 (5)	0.0256 (4)	0.0020 (3)	0.0020 (3)	−0.0037 (3)
O4	0.0340 (5)	0.0237 (5)	0.0280 (4)	0.0067 (4)	0.0025 (3)	−0.0041 (3)
N1	0.0242 (5)	0.0204 (5)	0.0259 (5)	0.0032 (4)	0.0031 (4)	−0.0023 (4)
N2	0.0226 (5)	0.0181 (5)	0.0287 (5)	0.0000 (4)	0.0040 (4)	−0.0044 (4)
C1	0.0224 (6)	0.0187 (6)	0.0322 (6)	0.0036 (5)	0.0054 (5)	−0.0008 (5)
C2	0.0213 (6)	0.0224 (6)	0.0334 (6)	0.0026 (5)	0.0004 (5)	−0.0041 (5)
C3	0.0240 (6)	0.0204 (6)	0.0328 (6)	−0.0003 (5)	0.0053 (5)	−0.0014 (5)
C4	0.0197 (6)	0.0202 (6)	0.0305 (6)	0.0034 (5)	0.0037 (4)	0.0000 (5)
C5	0.0354 (7)	0.0269 (7)	0.0292 (6)	−0.0024 (5)	0.0058 (5)	−0.0024 (5)
C6	0.0286 (6)	0.0266 (7)	0.0274 (6)	0.0056 (5)	0.0003 (5)	0.0015 (5)
C7	0.0267 (6)	0.0223 (6)	0.0197 (5)	0.0022 (5)	0.0012 (4)	0.0043 (4)
C8	0.0225 (6)	0.0276 (7)	0.0229 (6)	−0.0012 (5)	−0.0011 (4)	0.0016 (5)
C9	0.0285 (6)	0.0222 (6)	0.0212 (6)	−0.0012 (5)	−0.0009 (4)	−0.0016 (4)
C10	0.0252 (6)	0.0232 (6)	0.0158 (5)	0.0029 (5)	0.0022 (4)	0.0025 (4)
C11	0.0238 (6)	0.0279 (7)	0.0233 (6)	−0.0039 (5)	0.0012 (4)	0.0000 (5)
C12	0.0317 (6)	0.0214 (6)	0.0214 (5)	−0.0007 (5)	0.0024 (5)	−0.0005 (5)
C13	0.0234 (6)	0.0330 (7)	0.0316 (6)	0.0002 (5)	0.0049 (5)	0.0002 (5)
C14	0.0236 (6)	0.0220 (6)	0.0334 (6)	−0.0016 (5)	0.0003 (5)	−0.0049 (5)
C15	0.0196 (6)	0.0174 (6)	0.0303 (6)	−0.0033 (4)	0.0022 (4)	−0.0034 (5)
C16	0.0257 (6)	0.0228 (6)	0.0225 (5)	−0.0043 (5)	0.0036 (4)	−0.0023 (5)
C17	0.0264 (6)	0.0226 (6)	0.0237 (6)	−0.0017 (5)	−0.0008 (4)	0.0015 (5)
C18	0.0223 (6)	0.0173 (6)	0.0277 (6)	−0.0022 (5)	0.0027 (4)	−0.0023 (5)
C19	0.0301 (6)	0.0234 (6)	0.0217 (6)	−0.0025 (5)	0.0010 (4)	−0.0031 (5)
C20	0.0278 (6)	0.0209 (6)	0.0260 (6)	−0.0004 (5)	−0.0029 (4)	0.0016 (5)
C21	0.0394 (7)	0.0273 (7)	0.0309 (7)	0.0042 (6)	0.0067 (5)	−0.0069 (5)

Geometric parameters (Å, º) top

O1—C1	1.2220 (13)	C9—C10	1.3922 (15)
O2—C2	1.2276 (14)	C9—H9	0.9500
O3—C10	1.3677 (13)	C10—C11	1.3886 (16)
O3—C13	1.4288 (13)	C11—C12	1.3929 (15)
O4—C18	1.3723 (13)	C11—H11	0.9500
O4—C21	1.4292 (14)	C12—H12	0.9500
N1—C1	1.3848 (15)	C13—H13A	0.9800
N1—C2	1.4070 (15)	C13—H13B	0.9800
N1—C6	1.4853 (14)	C13—H13C	0.9800
N2—C4	1.3838 (14)	C14—C15	1.5142 (15)
N2—C1	1.3904 (14)	C14—H14A	0.9900
N2—C14	1.4803 (14)	C14—H14B	0.9900
C2—C3	1.4290 (15)	C15—C20	1.3850 (15)
C3—C4	1.3444 (16)	C15—C16	1.3954 (16)
C3—H3	0.9500	C16—C17	1.3770 (16)
C4—C5	1.4914 (15)	C16—H16	0.9500
C5—H5A	0.9800	C17—C18	1.3949 (15)
C5—H5B	0.9800	C17—H17	0.9500
C5—H5C	0.9800	C18—C19	1.3879 (16)
C6—C7	1.5108 (15)	C19—C20	1.3901 (16)
C6—H6A	0.9900	C19—H19	0.9500
C6—H6B	0.9900	C20—H20	0.9500
C7—C12	1.3850 (15)	C21—H21A	0.9800
C7—C8	1.3946 (16)	C21—H21B	0.9800
C8—C9	1.3814 (15)	C21—H21C	0.9800
C8—H8	0.9500

C10—O3—C13	116.79 (9)	C11—C10—C9	120.04 (10)
C18—O4—C21	116.59 (9)	C10—C11—C12	119.15 (11)
C1—N1—C2	124.87 (9)	C10—C11—H11	120.4
C1—N1—C6	117.30 (9)	C12—C11—H11	120.4
C2—N1—C6	117.78 (9)	C7—C12—C11	121.40 (11)
C4—N2—C1	121.75 (9)	C7—C12—H12	119.3
C4—N2—C14	121.65 (9)	C11—C12—H12	119.3
C1—N2—C14	116.56 (9)	O3—C13—H13A	109.5
O1—C1—N1	122.15 (11)	O3—C13—H13B	109.5
O1—C1—N2	121.67 (10)	H13A—C13—H13B	109.5
N1—C1—N2	116.18 (10)	O3—C13—H13C	109.5
O2—C2—N1	119.80 (10)	H13A—C13—H13C	109.5
O2—C2—C3	125.52 (11)	H13B—C13—H13C	109.5
N1—C2—C3	114.68 (10)	N2—C14—C15	114.07 (9)
C4—C3—C2	121.90 (11)	N2—C14—H14A	108.7
C4—C3—H3	119.0	C15—C14—H14A	108.7
C2—C3—H3	119.0	N2—C14—H14B	108.7
C3—C4—N2	120.60 (10)	C15—C14—H14B	108.7
C3—C4—C5	121.37 (11)	H14A—C14—H14B	107.6
N2—C4—C5	118.03 (10)	C20—C15—C16	117.80 (10)
C4—C5—H5A	109.5	C20—C15—C14	120.46 (10)
C4—C5—H5B	109.5	C16—C15—C14	121.70 (10)
H5A—C5—H5B	109.5	C17—C16—C15	121.49 (10)
C4—C5—H5C	109.5	C17—C16—H16	119.3
H5A—C5—H5C	109.5	C15—C16—H16	119.3
H5B—C5—H5C	109.5	C16—C17—C18	119.94 (10)
N1—C6—C7	114.63 (9)	C16—C17—H17	120.0
N1—C6—H6A	108.6	C18—C17—H17	120.0
C7—C6—H6A	108.6	O4—C18—C19	124.37 (10)
N1—C6—H6B	108.6	O4—C18—C17	116.09 (10)
C7—C6—H6B	108.6	C19—C18—C17	119.54 (10)
H6A—C6—H6B	107.6	C18—C19—C20	119.54 (10)
C12—C7—C8	118.64 (10)	C18—C19—H19	120.2
C12—C7—C6	120.28 (11)	C20—C19—H19	120.2
C8—C7—C6	121.04 (10)	C15—C20—C19	121.68 (10)
C9—C8—C7	120.71 (11)	C15—C20—H20	119.2
C9—C8—H8	119.6	C19—C20—H20	119.2
C7—C8—H8	119.6	O4—C21—H21A	109.5
C8—C9—C10	120.06 (11)	O4—C21—H21B	109.5
C8—C9—H9	120.0	H21A—C21—H21B	109.5
C10—C9—H9	120.0	O4—C21—H21C	109.5
O3—C10—C11	124.45 (10)	H21A—C21—H21C	109.5
O3—C10—C9	115.51 (10)	H21B—C21—H21C	109.5

C2—N1—C1—O1	179.48 (10)	C7—C8—C9—C10	−0.49 (16)
C6—N1—C1—O1	2.11 (16)	C13—O3—C10—C11	−1.51 (15)
C2—N1—C1—N2	−0.05 (15)	C13—O3—C10—C9	178.71 (9)
C6—N1—C1—N2	−177.43 (9)	C8—C9—C10—O3	179.95 (9)
C4—N2—C1—O1	−178.01 (10)	C8—C9—C10—C11	0.15 (16)
C14—N2—C1—O1	4.12 (15)	O3—C10—C11—C12	−179.39 (10)
C4—N2—C1—N1	1.53 (15)	C9—C10—C11—C12	0.38 (16)
C14—N2—C1—N1	−176.34 (9)	C8—C7—C12—C11	0.28 (16)
C1—N1—C2—O2	179.50 (10)	C6—C7—C12—C11	177.94 (10)
C6—N1—C2—O2	−3.13 (15)	C10—C11—C12—C7	−0.60 (16)
C1—N1—C2—C3	−1.11 (15)	C4—N2—C14—C15	84.38 (13)
C6—N1—C2—C3	176.25 (9)	C1—N2—C14—C15	−97.75 (11)
O2—C2—C3—C4	−179.76 (12)	N2—C14—C15—C20	−126.06 (11)
N1—C2—C3—C4	0.89 (16)	N2—C14—C15—C16	56.27 (14)
C2—C3—C4—N2	0.48 (17)	C20—C15—C16—C17	−0.72 (16)
C2—C3—C4—C5	−179.79 (10)	C14—C15—C16—C17	177.00 (10)
C1—N2—C4—C3	−1.78 (16)	C15—C16—C17—C18	−0.11 (16)
C14—N2—C4—C3	175.98 (10)	C21—O4—C18—C19	−3.25 (15)
C1—N2—C4—C5	178.48 (10)	C21—O4—C18—C17	176.61 (10)
C14—N2—C4—C5	−3.75 (15)	C16—C17—C18—O4	−178.78 (9)
C1—N1—C6—C7	−95.32 (12)	C16—C17—C18—C19	1.09 (16)
C2—N1—C6—C7	87.11 (12)	O4—C18—C19—C20	178.63 (10)
N1—C6—C7—C12	78.75 (13)	C17—C18—C19—C20	−1.22 (16)
N1—C6—C7—C8	−103.65 (12)	C16—C15—C20—C19	0.58 (16)
C12—C7—C8—C9	0.27 (16)	C14—C15—C20—C19	−177.17 (10)
C6—C7—C8—C9	−177.37 (10)	C18—C19—C20—C15	0.38 (17)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C20—H20···O3ⁱ	0.95	2.51	3.3627 (14)	150

Symmetry code: (i) x+1/2, −y+1/2, z−1/2.

Experimental details

Crystal data
Chemical formula	C₂₁H₂₂N₂O₄
M_r	366.41
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	113
a, b, c (Å)	8.4133 (9), 9.929 (1), 21.407 (3)
β (°)	91.614 (4)
V (Å³)	1787.5 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.26 × 0.24 × 0.22

Data collection
Diffractometer	Rigaku Saturn724 CCD diffractometer
Absorption correction	Multi-scan (CrystalClear; Rigaku/MSC, 2009)
T_min, T_max	0.976, 0.979
No. of measured, independent and observed [I > 2σ(I)] reflections	17394, 4250, 3035
R_int	0.037
(sin θ/λ)_max (Å⁻¹)	0.658

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.096, 0.98
No. of reflections	4250
No. of parameters	247
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.29, −0.16

Computer programs: CrystalClear (Rigaku/MSC, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), CrystalStructure (Rigaku/MSC, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C20—H20···O3ⁱ	0.95	2.51	3.3627 (14)	150.1

Symmetry code: (i) x+1/2, −y+1/2, z−1/2.

Acknowledgements

This work was supported by the Program for New Century Excellent Talents at the University of Henan Province (No. 2005HANCET-17), the Natural Science Foundation of Henan Province, China (grant No. 082300420110) and the Natural Science Foundation of Henan Province Education Department, China (grant No. 2007150036).

References

Condon, M. E., Brady, T. E., Feist, D., Malefyt, T., Marc, P., Quakenbush, L. S., Rodaway, S. J., Shaner, D. L. & Tecle, B. (1993). Brighton Crop Protection Conference on Weeds, pp. 41–46. Alton, Hampshire, England: BCPC Publications. Google Scholar
Gilchrist, T. L. (1997). Heterocyclic Chemistry, 3rd ed., pp. 261–276. Singapore: Addison Wesley Longman. Google Scholar
Maeno, S., Miura, I., Masuda, K. & Nagata, T. (1990). Brighton Crop Protection Conference on Pests and Diseases, pp. 415–422. Alton, Hampshire, England: BCPC Publications. Google Scholar
Rigaku/MSC (2009). CrystalClear and CrystalStructure. Rigaku/MSC, The Woodlands, Texas, USA. Google Scholar
Selby, T. P., Drumm, J. E., Coats, R. A., Coppo, F. T., Gee, S. K., Hay, J. V., Pasteris, R. J. & Stevenson, T. M. (2002). ACS Symposium Series, Vol. 800, Synthesis and Chemistry of Agrochemicals VI, pp. 74–84. Washington DC: American Chemical Society. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Yang, F.-L. & Li, G.-C. (2006). Acta Cryst. E62, o3405–o3406. Web of Science CSD CrossRef IUCr Journals Google Scholar
Zhu, Y.-Q., Zou, X.-M., Li, G.-C., Yao, C.-S. & Yang, H.-Z. (2007). Chin. J. Org. Chem. 27, 753–757. CAS Google Scholar