N6,3′-cyclo-5′-O-Cyano­methyl­thymidine

Sun, J.; Yang, K.; Duan, R.; Wu, J.

doi:10.1107/S1600536810019379

organic compounds

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ISSN: 2056-9890

Volume 66| Part 6| June 2010| Page o1512

https://doi.org/10.1107/S1600536810019379

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N⁶,3′-cyclo-5′-O-Cyanomethylthymidine

Jingbo Sun,^a Kun Yang,^a Ronghui Duan ^a and Jinchang Wu ^a ^*

^aCollege of Chemistry, Jilin University, Changchun 130012, People's Republic of China
^*Correspondence e-mail: sunjb@jlu.edu.cn

(Received 6 April 2010; accepted 24 May 2010; online 29 May 2010)

The title compound, C₁₉H₂₀N₄O₄, is a cyclonucleoside with a C—N linkage. The furanose ring adopts a twist C3′-endo/C2′-exo (close to ³T₂) conformation with a pseudorotational phase angle (P) of 8.1° and puckering amplitude (v_m) of 30.6°. The orientation of the pyrimidine ring with respect to the sugar group is anti. One intramolecular C—H⋯O hydrogen bond is observed. The packing features an N—H⋯O hydrogen bond.

Related literature

For nucleosides, see: Kaur et al. (2007 ); Imanishi & Satoshi (2002 ); Len et al. (2008 ); Mieczkowski et al. (2010 ); Sanger (1984 ); Altona & Sundaralingam (1972 , 1973 ); Zhou & Chattopadhyaya (2009 ).

Experimental

Crystal data

C₁₉H₂₀N₄O₄
M_r = 368.39
Orthorhombic, P 2₁ 2₁ 2₁
a = 10.1682 (7) Å
b = 11.0867 (8) Å
c = 15.8882 (11) Å
V = 1791.1 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 295 K
0.15 × 0.11 × 0.09 mm

Data collection

Bruker SMART 1000 diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.985, T_max = 0.991
10105 measured reflections
2036 independent reflections
1756 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.079
S = 1.04
2036 reflections
249 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.18 e Å⁻³
Δρ_min = −0.15 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O3ⁱ	0.85 (2)	2.12 (2)	2.938 (2)	161 (2)
C6—H6⋯O2	0.93	2.89	3.492 (3)	123
Symmetry code: (i) $[-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 1998 ); cell refinement: SAINT (Bruker, 1998); 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: SHELXL97 (Sheldrick, 2008).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810019379/om2332sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810019379/om2332Isup2.hkl

checkCIF report

Comment top

Nucleosides with restricted conformations have attracted attention with the development of LNAs (Kaur, et al. 2007) and BNAs (Imanishi & Satoshi, 2002) in recent years. Cyclonucleosides in which there is a linkage between nucleobase and the sugar moiety of nucleosides constrains both the puckering of the sugar ring and the glycosyl torsion angle (Len, et al., 2008). Although many cyclonucleosides were synthesized since the early years (Mieczkowski, et al., 2010), the study of their conformations and evaluation of their biological properties is relatively rare. Here we report the structure of a cyclonucleoside with a C—N linkage between C6 and C2' of thymidine.

In the title compound (Fig. 1), the five-membered ribose ring C13/C14/C15/C16/O3 adopts a North conformation (close to ³T₂), with a pseudorotational phase angle (P) of 8.1° and puckering amplitude (v_m) of 30.6° (Sanger, 1984; Altona & Sundaralingam, 1972; Altona & Sundaralingam, 1973). The glycosydic torsion angle ξ (O3—C6—N1—C1) of 99.4 (18)° shows the orientation of the pyrimidine ring to be anti with respect to the sugar group. The torsion angle ρ (C8—C9—C12—N3) is 174.15 (15)°. The C15—N1 and C10—N1 bond lengths in the linkage are 1.463 (2) and 1.355 (2)Å, it is clearly that the bond between the nucleobase and linkage is nearly double bond because of conjugation. The linkage bond angle of C10—N1—C15 is 121.36 (16)°.

Related literature top

For nucleosides, see: Kaur et al. (2007); Imanishi & Satoshi (2002); Len et al. (2008); Mieczkowski et al. (2010); Sanger (1984); Altona & Sundaralingam (1972, 1973); Zhou & Chattopadhyaya (2009)

Experimental top

The compound was separated from refluxing toluene solution of 1-(3-azido-2,3-dideoxy-5-cyanomethyl-5-deoxy-β-D-threo-pentofuranosy1) thymine (manuscript in preparation). It was crystallized slowly from a mixture of ethanol and ethyl acetate(1:2) at 298 K.

Structure description top

For nucleosides, see: Kaur et al. (2007); Imanishi & Satoshi (2002); Len et al. (2008); Mieczkowski et al. (2010); Sanger (1984); Altona & Sundaralingam (1972, 1973); Zhou & Chattopadhyaya (2009)

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXL97 (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. View of the molecule of the title compound showing the atom labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.

N⁶,3'-cyclo-5'-O-Cyanomethylthymidine top

Crystal data top

C₁₉H₂₀N₄O₄	F(000) = 776
M_r = 368.39	D_x = 1.366 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 2856 reflections
a = 10.1682 (7) Å	θ = 2.2–26.1°
b = 11.0867 (8) Å	µ = 0.10 mm⁻¹
c = 15.8882 (11) Å	T = 295 K
V = 1791.1 (2) Å³	Block, colourless
Z = 4	0.15 × 0.11 × 0.09 mm

Data collection top

Bruker SMART 1000 diffractometer	2036 independent reflections
Radiation source: fine-focus sealed tube	1756 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.031
Detector resolution: 9.00 pixels mm^-1	θ_max = 26.1°, θ_min = 2.2°
φ and ω scans	h = −12→10
Absorption correction: multi-scan (SADABS; Bruker, 2001)	k = −13→13
T_min = 0.985, T_max = 0.991	l = −19→18
10105 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)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.079	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ²(F_o²) + (0.0361P)² + 0.3497P] where P = (F_o² + 2F_c²)/3
2036 reflections	(Δ/σ)_max < 0.001
249 parameters	Δρ_max = 0.18 e Å⁻³
0 restraints	Δρ_min = −0.15 e Å⁻³

Crystal data top

C₁₉H₂₀N₄O₄	V = 1791.1 (2) Å³
M_r = 368.39	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 10.1682 (7) Å	µ = 0.10 mm⁻¹
b = 11.0867 (8) Å	T = 295 K
c = 15.8882 (11) Å	0.15 × 0.11 × 0.09 mm

Data collection top

Bruker SMART 1000 diffractometer	2036 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2001)	1756 reflections with I > 2σ(I)
T_min = 0.985, T_max = 0.991	R_int = 0.031
10105 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	0 restraints
wR(F²) = 0.079	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	Δρ_max = 0.18 e Å⁻³
2036 reflections	Δρ_min = −0.15 e Å⁻³
249 parameters

Special details top

Experimental. (See detailed section in the paper)

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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	0.26037 (18)	0.41221 (14)	0.18977 (11)	0.0419 (4)
O2	0.2659 (2)	0.16696 (16)	−0.04016 (11)	0.0476 (5)
O3	0.01006 (15)	0.29016 (14)	0.30360 (10)	0.0331 (4)
O4	−0.26649 (17)	0.29459 (15)	0.27577 (11)	0.0414 (4)
N1	0.0436 (2)	0.04989 (18)	0.20934 (13)	0.0322 (5)
H1	0.034 (2)	−0.023 (2)	0.1935 (14)	0.027 (6)*
N2	0.16403 (18)	0.22763 (16)	0.20033 (12)	0.0280 (4)
N3	0.2616 (2)	0.29017 (17)	0.07452 (12)	0.0345 (5)
N4	−0.5475 (2)	0.1380 (3)	0.2508 (2)	0.0720 (8)
C1	0.2157 (3)	0.4766 (2)	−0.00647 (16)	0.0382 (6)
C2	0.2429 (3)	0.5985 (2)	−0.01234 (16)	0.0434 (7)
H2	0.3247	0.6274	0.0044	0.052*
C3	0.1488 (3)	0.6782 (2)	−0.04317 (17)	0.0481 (7)
H3	0.1688	0.7598	−0.0476	0.058*
C4	0.0270 (3)	0.6379 (3)	−0.06705 (17)	0.0493 (7)
H4	−0.0360	0.6917	−0.0867	0.059*
C5	−0.0002 (3)	0.5186 (3)	−0.0617 (2)	0.0651 (9)
H5	−0.0823	0.4903	−0.0784	0.078*
C6	0.0925 (3)	0.4386 (3)	−0.0316 (2)	0.0612 (9)
H6	0.0715	0.3571	−0.0282	0.073*
C7	0.3192 (3)	0.3888 (2)	0.02538 (17)	0.0415 (6)
H7A	0.3665	0.3554	−0.0222	0.050*
H7B	0.3819	0.4321	0.0601	0.050*
C8	0.2318 (3)	0.1800 (2)	0.03381 (15)	0.0343 (5)
C9	0.1612 (2)	0.0937 (2)	0.08223 (15)	0.0316 (5)
C10	0.1238 (2)	0.12081 (19)	0.16251 (15)	0.0277 (5)
C11	0.2314 (2)	0.3165 (2)	0.15690 (15)	0.0314 (5)
C12	0.1264 (3)	−0.0252 (2)	0.04249 (17)	0.0399 (6)
H12A	0.1788	−0.0880	0.0672	0.060*
H12B	0.1433	−0.0215	−0.0169	0.060*
H12C	0.0349	−0.0420	0.0518	0.060*
C13	0.1405 (2)	0.2471 (2)	0.29099 (15)	0.0301 (5)
H13	0.2054	0.3027	0.3149	0.036*
C14	0.1430 (2)	0.1270 (2)	0.33571 (15)	0.0348 (6)
H14A	0.1374	0.1356	0.3964	0.042*
H14B	0.2197	0.0794	0.3210	0.042*
C15	0.0176 (2)	0.0765 (2)	0.29797 (14)	0.0317 (5)
H15	−0.0133	0.0051	0.3285	0.038*
C16	−0.0762 (2)	0.1842 (2)	0.30890 (15)	0.0315 (5)
H16	−0.1137	0.1809	0.3657	0.038*
C17	−0.1865 (2)	0.1961 (2)	0.24724 (16)	0.0350 (5)
H17A	−0.1524	0.2125	0.1914	0.042*
H17B	−0.2376	0.1223	0.2452	0.042*
C18	−0.3794 (3)	0.3126 (3)	0.22543 (18)	0.0475 (7)
H18A	−0.3540	0.3150	0.1666	0.057*
H18B	−0.4192	0.3895	0.2395	0.057*
C19	−0.4758 (3)	0.2153 (3)	0.23850 (19)	0.0499 (7)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0471 (11)	0.0284 (9)	0.0502 (10)	−0.0092 (9)	0.0064 (9)	−0.0036 (8)
O2	0.0649 (13)	0.0443 (11)	0.0336 (10)	0.0056 (10)	0.0107 (9)	0.0019 (8)
O3	0.0327 (9)	0.0251 (8)	0.0416 (9)	0.0000 (7)	0.0067 (8)	−0.0025 (7)
O4	0.0349 (9)	0.0366 (9)	0.0525 (11)	0.0061 (8)	0.0015 (8)	−0.0049 (8)
N1	0.0373 (12)	0.0202 (10)	0.0391 (12)	−0.0018 (9)	0.0062 (9)	−0.0028 (9)
N2	0.0299 (10)	0.0229 (9)	0.0313 (10)	−0.0010 (8)	0.0031 (8)	−0.0003 (8)
N3	0.0366 (11)	0.0300 (10)	0.0368 (11)	−0.0005 (9)	0.0073 (9)	0.0067 (9)
N4	0.0401 (15)	0.0722 (18)	0.104 (2)	−0.0030 (14)	0.0069 (16)	−0.0095 (18)
C1	0.0470 (16)	0.0323 (13)	0.0354 (13)	−0.0036 (11)	0.0094 (12)	0.0060 (10)
C2	0.0494 (16)	0.0363 (14)	0.0445 (15)	−0.0087 (14)	0.0147 (13)	−0.0039 (11)
C3	0.075 (2)	0.0226 (12)	0.0470 (16)	0.0023 (13)	0.0218 (15)	0.0018 (12)
C4	0.063 (2)	0.0403 (16)	0.0445 (16)	0.0120 (14)	0.0054 (14)	0.0070 (12)
C5	0.0517 (18)	0.0491 (19)	0.094 (3)	−0.0004 (15)	−0.0155 (19)	0.0119 (17)
C6	0.0521 (19)	0.0343 (15)	0.097 (3)	−0.0099 (13)	−0.0142 (18)	0.0167 (16)
C7	0.0393 (14)	0.0401 (15)	0.0451 (16)	−0.0067 (12)	0.0080 (12)	0.0072 (12)
C8	0.0381 (13)	0.0304 (12)	0.0345 (13)	0.0092 (11)	0.0015 (11)	0.0026 (10)
C9	0.0340 (13)	0.0279 (12)	0.0330 (13)	0.0035 (10)	0.0009 (10)	−0.0009 (10)
C10	0.0262 (11)	0.0210 (11)	0.0359 (13)	0.0043 (9)	−0.0012 (10)	0.0011 (9)
C11	0.0281 (12)	0.0247 (11)	0.0416 (13)	0.0001 (9)	0.0025 (11)	0.0023 (10)
C12	0.0511 (16)	0.0314 (13)	0.0373 (14)	0.0026 (12)	−0.0013 (13)	−0.0036 (11)
C13	0.0291 (12)	0.0286 (12)	0.0327 (12)	−0.0011 (9)	0.0008 (10)	−0.0021 (10)
C14	0.0342 (14)	0.0377 (13)	0.0325 (13)	0.0012 (11)	−0.0003 (11)	0.0055 (11)
C15	0.0353 (13)	0.0267 (12)	0.0329 (13)	−0.0023 (10)	0.0058 (11)	0.0048 (10)
C16	0.0342 (12)	0.0276 (12)	0.0326 (12)	−0.0039 (10)	0.0080 (10)	0.0007 (10)
C17	0.0332 (13)	0.0281 (12)	0.0437 (14)	−0.0007 (10)	0.0063 (11)	−0.0036 (11)
C18	0.0406 (15)	0.0482 (16)	0.0539 (17)	0.0105 (13)	0.0022 (13)	0.0076 (13)
C19	0.0331 (14)	0.0575 (18)	0.0592 (18)	0.0073 (14)	0.0008 (13)	−0.0053 (15)

Geometric parameters (Å, º) top

O1—C11	1.219 (3)	C5—C6	1.380 (4)
O2—C8	1.234 (3)	C5—H5	0.9300
O3—C13	1.424 (3)	C6—H6	0.9300
O3—C16	1.468 (3)	C7—H7A	0.9700
O4—C18	1.413 (3)	C7—H7B	0.9700
O4—C17	1.435 (3)	C8—C9	1.422 (3)
N1—C10	1.355 (3)	C9—C10	1.365 (3)
N1—C15	1.463 (3)	C9—C12	1.504 (3)
N1—H1	0.85 (2)	C12—H12A	0.9600
N2—C11	1.384 (3)	C12—H12B	0.9600
N2—C10	1.390 (3)	C12—H12C	0.9600
N2—C13	1.476 (3)	C13—C14	1.509 (3)
N3—C11	1.376 (3)	C13—H13	0.9800
N3—C8	1.415 (3)	C14—C15	1.517 (3)
N3—C7	1.466 (3)	C14—H14A	0.9700
N4—C19	1.142 (4)	C14—H14B	0.9700
C1—C6	1.381 (4)	C15—C16	1.539 (3)
C1—C2	1.382 (4)	C15—H15	0.9800
C1—C7	1.520 (4)	C16—C17	1.495 (3)
C2—C3	1.392 (4)	C16—H16	0.9800
C2—H2	0.9300	C17—H17A	0.9700
C3—C4	1.370 (4)	C17—H17B	0.9700
C3—H3	0.9300	C18—C19	1.472 (4)
C4—C5	1.354 (4)	C18—H18A	0.9700
C4—H4	0.9300	C18—H18B	0.9700

C13—O3—C16	107.23 (16)	O1—C11—N2	121.7 (2)
C18—O4—C17	112.91 (19)	N3—C11—N2	115.7 (2)
C10—N1—C15	121.4 (2)	C9—C12—H12A	109.5
C10—N1—H1	117.2 (16)	C9—C12—H12B	109.5
C15—N1—H1	117.0 (16)	H12A—C12—H12B	109.5
C11—N2—C10	122.47 (19)	C9—C12—H12C	109.5
C11—N2—C13	117.56 (19)	H12A—C12—H12C	109.5
C10—N2—C13	119.92 (19)	H12B—C12—H12C	109.5
C11—N3—C8	124.78 (19)	O3—C13—N2	109.69 (18)
C11—N3—C7	115.9 (2)	O3—C13—C14	104.21 (18)
C8—N3—C7	119.09 (19)	N2—C13—C14	109.15 (19)
C6—C1—C2	117.4 (3)	O3—C13—H13	111.2
C6—C1—C7	121.9 (2)	N2—C13—H13	111.2
C2—C1—C7	120.6 (2)	C14—C13—H13	111.2
C1—C2—C3	120.4 (3)	C13—C14—C15	97.21 (19)
C1—C2—H2	119.8	C13—C14—H14A	112.3
C3—C2—H2	119.8	C15—C14—H14A	112.3
C4—C3—C2	120.8 (3)	C13—C14—H14B	112.3
C4—C3—H3	119.6	C15—C14—H14B	112.3
C2—C3—H3	119.6	H14A—C14—H14B	109.9
C5—C4—C3	119.1 (3)	N1—C15—C14	107.63 (19)
C5—C4—H4	120.5	N1—C15—C16	112.16 (19)
C3—C4—H4	120.5	C14—C15—C16	100.96 (18)
C4—C5—C6	120.6 (3)	N1—C15—H15	111.8
C4—C5—H5	119.7	C14—C15—H15	111.8
C6—C5—H5	119.7	C16—C15—H15	111.8
C5—C6—C1	121.6 (3)	O3—C16—C17	109.88 (18)
C5—C6—H6	119.2	O3—C16—C15	104.13 (17)
C1—C6—H6	119.2	C17—C16—C15	117.36 (19)
N3—C7—C1	112.2 (2)	O3—C16—H16	108.4
N3—C7—H7A	109.2	C17—C16—H16	108.4
C1—C7—H7A	109.2	C15—C16—H16	108.4
N3—C7—H7B	109.2	O4—C17—C16	106.58 (19)
C1—C7—H7B	109.2	O4—C17—H17A	110.4
H7A—C7—H7B	107.9	C16—C17—H17A	110.4
O2—C8—N3	118.5 (2)	O4—C17—H17B	110.4
O2—C8—C9	125.3 (2)	C16—C17—H17B	110.4
N3—C8—C9	116.2 (2)	H17A—C17—H17B	108.6
C10—C9—C8	119.9 (2)	O4—C18—C19	110.9 (2)
C10—C9—C12	121.3 (2)	O4—C18—H18A	109.5
C8—C9—C12	118.8 (2)	C19—C18—H18A	109.5
N1—C10—C9	123.6 (2)	O4—C18—H18B	109.5
N1—C10—N2	115.7 (2)	C19—C18—H18B	109.5
C9—C10—N2	120.6 (2)	H18A—C18—H18B	108.0
O1—C11—N3	122.6 (2)	N4—C19—C18	177.4 (3)

C6—C1—C2—C3	−0.5 (4)	C8—N3—C11—O1	179.1 (2)
C7—C1—C2—C3	178.7 (2)	C7—N3—C11—O1	−6.0 (3)
C1—C2—C3—C4	1.0 (4)	C8—N3—C11—N2	−1.7 (3)
C2—C3—C4—C5	−1.1 (4)	C7—N3—C11—N2	173.2 (2)
C3—C4—C5—C6	0.8 (5)	C10—N2—C11—O1	176.3 (2)
C4—C5—C6—C1	−0.3 (6)	C13—N2—C11—O1	−6.4 (3)
C2—C1—C6—C5	0.2 (5)	C10—N2—C11—N3	−2.9 (3)
C7—C1—C6—C5	−179.0 (3)	C13—N2—C11—N3	174.4 (2)
C11—N3—C7—C1	−80.4 (3)	C16—O3—C13—N2	85.9 (2)
C8—N3—C7—C1	94.8 (3)	C16—O3—C13—C14	−30.8 (2)
C6—C1—C7—N3	−35.9 (4)	C11—N2—C13—O3	99.4 (2)
C2—C1—C7—N3	145.0 (2)	C10—N2—C13—O3	−83.3 (2)
C11—N3—C8—O2	−179.0 (2)	C11—N2—C13—C14	−147.0 (2)
C7—N3—C8—O2	6.3 (3)	C10—N2—C13—C14	30.3 (3)
C11—N3—C8—C9	2.4 (3)	O3—C13—C14—C15	48.7 (2)
C7—N3—C8—C9	−172.4 (2)	N2—C13—C14—C15	−68.4 (2)
O2—C8—C9—C10	−177.0 (2)	C10—N1—C15—C14	−35.7 (3)
N3—C8—C9—C10	1.5 (3)	C10—N1—C15—C16	74.5 (3)
O2—C8—C9—C12	1.4 (4)	C13—C14—C15—N1	70.8 (2)
N3—C8—C9—C12	179.9 (2)	C13—C14—C15—C16	−46.9 (2)
C15—N1—C10—C9	173.5 (2)	C13—O3—C16—C17	−126.6 (2)
C15—N1—C10—N2	−8.5 (3)	C13—O3—C16—C15	−0.1 (2)
C8—C9—C10—N1	172.0 (2)	N1—C15—C16—O3	−84.0 (2)
C12—C9—C10—N1	−6.3 (4)	C14—C15—C16—O3	30.3 (2)
C8—C9—C10—N2	−5.9 (3)	N1—C15—C16—C17	37.7 (3)
C12—C9—C10—N2	175.7 (2)	C14—C15—C16—C17	152.0 (2)
C11—N2—C10—N1	−171.3 (2)	C18—O4—C17—C16	−176.96 (19)
C13—N2—C10—N1	11.5 (3)	O3—C16—C17—O4	−67.2 (2)
C11—N2—C10—C9	6.8 (3)	C15—C16—C17—O4	174.11 (18)
C13—N2—C10—C9	−170.4 (2)	C17—O4—C18—C19	71.4 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O3ⁱ	0.85 (2)	2.12 (2)	2.938 (2)	161 (2)
C6—H6···O2	0.93	2.89	3.492 (3)	123

Symmetry code: (i) −x, y−1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula	C₁₉H₂₀N₄O₄
M_r	368.39
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	295
a, b, c (Å)	10.1682 (7), 11.0867 (8), 15.8882 (11)
V (Å³)	1791.1 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.15 × 0.11 × 0.09

Data collection
Diffractometer	Bruker SMART 1000
Absorption correction	Multi-scan (SADABS; Bruker, 2001)
T_min, T_max	0.985, 0.991
No. of measured, independent and observed [I > 2σ(I)] reflections	10105, 2036, 1756
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.619

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.034, 0.079, 1.04
No. of reflections	2036
No. of parameters	249
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.18, −0.15

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O3ⁱ	0.85 (2)	2.12 (2)	2.938 (2)	161 (2)
C6—H6···O2	0.93	2.89	3.492 (3)	123.2

Symmetry code: (i) −x, y−1/2, −z+1/2.

Acknowledgements

We thank the National Natural Science Foundation of China (grant No. 20572034). JS is grateful for the support from the Jilin University.

References

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