6-Isopropyl-5-meth­oxy-3-phenyl-3H-1,2,3-triazolo[4,5-d]pyrimidin-7(6H)-one

Zeng, X.-H.; Wang, H.-M.; Deng, S.-H.; Chen, L.-L.

doi:10.1107/S1600536810041978

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 66| Part 11| November 2010| Pages o2947-o2948

https://doi.org/10.1107/S1600536810041978

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6-Isopropyl-5-methoxy-3-phenyl-3H-1,2,3-triazolo[4,5-d]pyrimidin-7(6H)-one

Xiao-Hua Zeng,^a Hong-Mei Wang,^a Shou-Heng Deng ^b ^* and Li-Li Chen ^a

^aInstitute of Medicinal Chemistry, Hubei Medical University, Shiyan 442000, People's Republic of China, and ^bCenter of Oncology, People's Hospital affiliated with Hubei Medical University, Shi Yan 442000, People's Republic of China
^*Correspondence e-mail: zken710@yahoo.com.cn

(Received 9 October 2010; accepted 16 October 2010; online 30 October 2010)

In the title compound, C₁₄H₁₅N₅O₂, the whole molecule apart from the terminal C atoms of the isopropyl group is located on a crystallographic mirror plane. An intramolecular C—H⋯N hydrogen-bonding interaction may stabilize the molecular conformation. The crystal packing features weak slipped π–π interactions between the pyrimidine and the phenyl rings of symmetry-related molecules [centroid–centroid distance = 3.746 (1)Å, slippage of 1.574 Å].

Related literature

Fpr the biological activity of 8-azaguanine derivatives, see: Roblin et al. (1945 ); Ding et al. (2004 ); Mitchell et al. (1950 ); Levine et al. (1963 ); Montgomery et al. (1962 ); Yamamoto et al. (1967 ); Bariana (1971 ); Holland et al. (1975 ). For related structures, see: Chen & Shi (2006 ); Ferguson et al. (1998 ); Li et al. (2004 ); Maldonado et al. (2006 ); Wang et al. (2006 ); Xiao & Shi (2007 ); Zeng et al. (2006 , 2009 ); Zhao, Hu et al. (2005 ); Zhao, Wang & Ding (2005 ); Zhao, Xie et al. (2005 ).

Experimental

Crystal data

C₁₄H₁₅N₅O₂
M_r = 285.31
Orthorhombic, P n m a
a = 14.921 (2) Å
b = 6.7989 (11) Å
c = 13.839 (2) Å
V = 1404.0 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 298 K
0.16 × 0.12 × 0.10 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2008 ) T_min = 0.985, T_max = 0.991
7422 measured reflections
1418 independent reflections
1045 reflections with I > 2σ(I)
R_int = 0.039

Refinement

R[F² > 2σ(F²)] = 0.065
wR(F²) = 0.185
S = 1.07
1418 reflections
125 parameters
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.29 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯N4	0.93	2.37	3.021 (4)	127

Data collection: SMART (Bruker, 2001 ); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ), ORTEP-3 for Windows (Farrugia, 1999 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810041978/dn2610sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810041978/dn2610Isup2.hkl

checkCIF report

Comment top

The derivatives of heterocycles containing 8-azaguanine system, which are well known bioisosteres of guanine, are of great importance because of their remarkable biological properties, such as antimicrobial or antifungal activities (Roblin et al., 1945; Ding et al., 2004), encephaloma cell inhibitor (Mitchell et al., 1950; Levine et al., 1963), antileukemie (Montgomery et al., 1962), hypersusceptibility inhibitor and acesodyne activities (Yamamoto et al., 1967; Bariana, 1971; Holland et al., 1975).

In recent years, Zhao's group succeeded in synthesizing the derivatives of 8-azaguanine via aza-Wittig reaction of beta-ethoxycarbonyl iminophosphorane with aromatic isocyanates (Zhao, Xie et al., 2005). As a continuation of the quest for new biologically active derivatives of 8-azaguanine, the title compound, (I), was obtained from beta-ethoxycarbonyl iminophosphorane with aliphatic isocyanate, and structurally characterized.

In the title compound, C₁₄H₁₅N₅O₂, the whole molecule but the terminal C atoms of the isopropyl group is located in a mirror plane and is then perfectly planar (Fig. 1). The bond lengths and angles in the triazolopyrimidinone moiety are in good agreement with those observed for closely related structures (Zhao, Hu et al., 2005; Zhao, Wang & Ding, 2005). the triazolopyrimidine ring system is perfectly coplanar (Chen & Shi, 2006; Ferguson et al., 1998; Li et al., 2004; Maldonado et al., 2006; Wang et al., 2006; Xiao & Shi, 2007; Zeng et al., 2009).

The molecules are packed along the b axis with weak slippest π–π interaction between the pyrimidin and the phenyl rings of symmetry related molecules (Centroid to centroid distance= 3.746 (1)Å, interplanar distance= 3.399 Å with a slippage of 1.574 Å).

Related literature top

Fpr the biological activity of 8-azaguanine derivatives, see: Roblin et al. (1945); Ding et al. (2004); Mitchell et al. (1950); Levine et al. (1963); Montgomery et al. (1962); Yamamoto et al. (1967); Bariana (1971); Holland et al. (1975). For related structures, see: Chen & Shi (2006); Ferguson et al. (1998); Li et al. (2004); Maldonado et al. (2006); Wang et al. (2006); Xiao & Shi (2007); Zeng et al. (2006, 2009); Zhao, Hu et al. (2005); Zhao, Wang & Ding (2005); Zhao, Xie et al. (2005).

Experimental top

To the solution of carbodiimide prepared according to Zeng et al. (2006) in a mixed solvent (CH₂Cl₂/MeOH,1:4 v/v, 15 ml) was added a fresh prepared solution of Na/MeOH (0.1 g/2 ml). After stirring the reaction mixture for 6 h, the solvent was removed under reduced pressure and the residue was recrystallized from EtOH to give the title compound (I) in 89% yield (m.p. 471 K). Elemental analysis: calculated for C₁₄H₁₅N₅O₂: C, 58.94; H, 5.30; N, 24.55%. Found: C, 57.62; H, 5.72; N, 24.01%. Crystals suitable for X-ray diffraction study were obtained by recrystallization from hexane and dichloromethane (1:3 v/v) at room temperature.

Structure description top

Fpr the biological activity of 8-azaguanine derivatives, see: Roblin et al. (1945); Ding et al. (2004); Mitchell et al. (1950); Levine et al. (1963); Montgomery et al. (1962); Yamamoto et al. (1967); Bariana (1971); Holland et al. (1975). For related structures, see: Chen & Shi (2006); Ferguson et al. (1998); Li et al. (2004); Maldonado et al. (2006); Wang et al. (2006); Xiao & Shi (2007); Zeng et al. (2006, 2009); Zhao, Hu et al. (2005); Zhao, Wang & Ding (2005); Zhao, Xie et al. (2005).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1999) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. View of the molecule of showing the atom-labeling scheme. Displacement ellipsoids are drawn at the 30% probability level. H-atoms are reprsented as small spheres of arbitrary radii. [Symmetry code: (i) -x-1/2, y+1/2, z-1/2].
	Fig. 2. Packing view showing the stacking of the molecules along the b axis. H atoms have been omitted for clarity.

6-Isopropyl-5-methoxy-3-phenyl-3H-1,2,3-triazolo[4,5- d]pyrimidin-7(6H)-one top

Crystal data top

C₁₄H₁₅N₅O₂	F(000) = 600
M_r = 285.31	D_x = 1.350 Mg m⁻³
Orthorhombic, Pnma	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2n	Cell parameters from 982 reflections
a = 14.921 (2) Å	θ = 2.9–20.5°
b = 6.7989 (11) Å	µ = 0.10 mm⁻¹
c = 13.839 (2) Å	T = 298 K
V = 1404.0 (4) Å³	Block, colourless
Z = 4	0.16 × 0.12 × 0.10 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	1418 independent reflections
Radiation source: fine-focus sealed tube	1045 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.039
φ and ω scans	θ_max = 25.5°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Sheldrick, 2008)	h = −17→18
T_min = 0.985, T_max = 0.991	k = −8→8
7422 measured reflections	l = −13→16

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)] = 0.065	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.185	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0883P)² + 0.4734P] where P = (F_o² + 2F_c²)/3
1418 reflections	(Δ/σ)_max < 0.001
125 parameters	Δρ_max = 0.23 e Å⁻³
0 restraints	Δρ_min = −0.29 e Å⁻³

Crystal data top

C₁₄H₁₅N₅O₂	V = 1404.0 (4) Å³
M_r = 285.31	Z = 4
Orthorhombic, Pnma	Mo Kα radiation
a = 14.921 (2) Å	µ = 0.10 mm⁻¹
b = 6.7989 (11) Å	T = 298 K
c = 13.839 (2) Å	0.16 × 0.12 × 0.10 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	1418 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2008)	1045 reflections with I > 2σ(I)
T_min = 0.985, T_max = 0.991	R_int = 0.039
7422 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.065	0 restraints
wR(F²) = 0.185	H-atom parameters constrained
S = 1.07	Δρ_max = 0.23 e Å⁻³
1418 reflections	Δρ_min = −0.29 e Å⁻³
125 parameters

Special details top

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	Occ. (<1)
O1	0.36483 (19)	0.2500	0.3850 (3)	0.1092 (13)
O2	0.24610 (18)	0.2500	0.6874 (2)	0.0829 (9)
N1	0.06296 (18)	0.2500	0.41475 (18)	0.0507 (7)
N2	0.0868 (3)	0.2500	0.3193 (2)	0.0843 (12)
N3	0.1730 (3)	0.2500	0.3126 (2)	0.0908 (12)
N4	0.14519 (17)	0.2500	0.5659 (2)	0.0495 (7)
N5	0.30395 (19)	0.2500	0.5368 (3)	0.0629 (9)
C1	−0.0298 (2)	0.2500	0.4402 (2)	0.0462 (8)
C2	−0.0554 (2)	0.2500	0.5362 (2)	0.0546 (9)
H2	−0.0124	0.2500	0.5848	0.065*
C3	−0.1452 (2)	0.2500	0.5591 (3)	0.0599 (10)
H3	−0.1626	0.2500	0.6236	0.072*
C4	−0.2092 (3)	0.2500	0.4886 (3)	0.0630 (10)
H4	−0.2697	0.2500	0.5049	0.076*
C5	−0.1835 (3)	0.2500	0.3938 (3)	0.0672 (11)
H5	−0.2270	0.2500	0.3457	0.081*
C6	−0.0949 (3)	0.2500	0.3683 (3)	0.0580 (10)
H6	−0.0783	0.2500	0.3035	0.070*
C7	0.1382 (2)	0.2500	0.4688 (2)	0.0464 (8)
C8	0.2070 (2)	0.2500	0.4039 (3)	0.0608 (10)
C9	0.2979 (3)	0.2500	0.4346 (3)	0.0721 (11)
C10	0.2277 (2)	0.2500	0.5942 (3)	0.0589 (9)
C11	0.3973 (3)	0.2500	0.5789 (4)	0.0879 (14)
H11	0.4338	0.2500	0.5200	0.105*
C12	0.4225 (2)	0.0624 (6)	0.6212 (3)	0.1210 (15)
H12A	0.4861	0.0599	0.6319	0.181*
H12B	0.4063	−0.0421	0.5780	0.181*
H12C	0.3919	0.0454	0.6816	0.181*
C13	0.1714 (3)	0.2500	0.7534 (3)	0.1016 (17)
H13A	0.1933	0.2500	0.8186	0.152*
H13B	0.1356	0.1347	0.7427	0.152*	0.50
H13C	0.1356	0.3653	0.7427	0.152*	0.50

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0561 (19)	0.156 (3)	0.115 (3)	0.000	0.0314 (18)	0.000
O2	0.0545 (17)	0.125 (3)	0.0687 (18)	0.000	−0.0150 (14)	0.000
N1	0.0539 (18)	0.0584 (17)	0.0399 (14)	0.000	0.0009 (13)	0.000
N2	0.075 (2)	0.131 (3)	0.0470 (19)	0.000	0.0067 (17)	0.000
N3	0.074 (3)	0.142 (4)	0.056 (2)	0.000	0.0142 (18)	0.000
N4	0.0419 (16)	0.0507 (16)	0.0559 (18)	0.000	−0.0071 (12)	0.000
N5	0.0365 (16)	0.0593 (19)	0.093 (2)	0.000	−0.0019 (15)	0.000
C1	0.050 (2)	0.0395 (17)	0.0485 (19)	0.000	−0.0052 (15)	0.000
C2	0.043 (2)	0.066 (2)	0.055 (2)	0.000	−0.0077 (16)	0.000
C3	0.052 (2)	0.065 (2)	0.063 (2)	0.000	0.0000 (17)	0.000
C4	0.047 (2)	0.060 (2)	0.082 (3)	0.000	−0.0074 (19)	0.000
C5	0.054 (2)	0.064 (2)	0.083 (3)	0.000	−0.030 (2)	0.000
C6	0.067 (3)	0.056 (2)	0.051 (2)	0.000	−0.0148 (18)	0.000
C7	0.048 (2)	0.0419 (18)	0.0497 (19)	0.000	−0.0003 (15)	0.000
C8	0.050 (2)	0.072 (2)	0.060 (2)	0.000	0.0094 (17)	0.000
C9	0.060 (3)	0.078 (3)	0.078 (3)	0.000	0.016 (2)	0.000
C10	0.055 (2)	0.055 (2)	0.067 (2)	0.000	−0.0120 (19)	0.000
C11	0.045 (2)	0.086 (3)	0.133 (4)	0.000	−0.013 (2)	0.000
C12	0.082 (2)	0.118 (3)	0.163 (4)	0.011 (2)	−0.034 (2)	0.043 (3)
C13	0.079 (3)	0.172 (5)	0.054 (2)	0.000	−0.016 (2)	0.000

Geometric parameters (Å, º) top

O1—C9	1.212 (5)	C3—H3	0.9300
O2—C10	1.319 (4)	C4—C5	1.367 (6)
O2—C13	1.441 (5)	C4—H4	0.9300
N1—C7	1.350 (4)	C5—C6	1.369 (5)
N1—N2	1.368 (4)	C5—H5	0.9300
N1—C1	1.428 (4)	C6—H6	0.9300
N2—N3	1.290 (5)	C7—C8	1.364 (5)
N3—C8	1.360 (5)	C8—C9	1.421 (5)
N4—C10	1.293 (4)	C11—C12ⁱ	1.453 (4)
N4—C7	1.348 (4)	C11—C12	1.453 (4)
N5—C10	1.387 (5)	C11—H11	0.9800
N5—C9	1.418 (5)	C12—H12A	0.9600
N5—C11	1.510 (5)	C12—H12B	0.9600
C1—C2	1.382 (5)	C12—H12C	0.9600
C1—C6	1.391 (4)	C13—H13A	0.9600
C2—C3	1.377 (5)	C13—H13B	0.9600
C2—H2	0.9300	C13—H13C	0.9600
C3—C4	1.365 (5)

C10—O2—C13	117.3 (3)	N4—C7—C8	126.8 (3)
C7—N1—N2	108.6 (3)	N1—C7—C8	105.1 (3)
C7—N1—C1	132.0 (3)	N3—C8—C7	109.4 (3)
N2—N1—C1	119.4 (3)	N3—C8—C9	129.3 (4)
N3—N2—N1	109.2 (3)	C7—C8—C9	121.4 (4)
N2—N3—C8	107.8 (3)	O1—C9—N5	120.8 (4)
C10—N4—C7	112.0 (3)	O1—C9—C8	128.1 (4)
C10—N5—C9	121.2 (3)	N5—C9—C8	111.1 (3)
C10—N5—C11	122.4 (4)	N4—C10—O2	119.6 (3)
C9—N5—C11	116.4 (3)	N4—C10—N5	127.5 (4)
C2—C1—C6	119.6 (3)	O2—C10—N5	112.9 (3)
C2—C1—N1	120.4 (3)	C12ⁱ—C11—C12	122.8 (5)
C6—C1—N1	120.0 (3)	C12ⁱ—C11—N5	113.2 (2)
C3—C2—C1	119.4 (3)	C12—C11—N5	113.2 (2)
C3—C2—H2	120.3	C12ⁱ—C11—H11	101.0
C1—C2—H2	120.3	C12—C11—H11	101.0
C4—C3—C2	121.1 (4)	N5—C11—H11	101.0
C4—C3—H3	119.5	C11—C12—H12A	109.5
C2—C3—H3	119.5	C11—C12—H12B	109.5
C3—C4—C5	119.3 (4)	H12A—C12—H12B	109.5
C3—C4—H4	120.3	C11—C12—H12C	109.5
C5—C4—H4	120.3	H12A—C12—H12C	109.5
C4—C5—C6	121.2 (3)	H12B—C12—H12C	109.5
C4—C5—H5	119.4	O2—C13—H13A	109.5
C6—C5—H5	119.4	O2—C13—H13B	109.5
C5—C6—C1	119.4 (3)	H13A—C13—H13B	109.5
C5—C6—H6	120.3	O2—C13—H13C	109.5
C1—C6—H6	120.3	H13A—C13—H13C	109.5
N4—C7—N1	128.1 (3)	H13B—C13—H13C	109.5

Symmetry code: (i) x, −y+1/2, z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···N4	0.93	2.37	3.021 (4)	127
C6—H6···N2	0.93	2.47	2.794 (5)	100
C11—H11···O1	0.98	2.13	2.727 (7)	117
C12—H12C···O2	0.96	2.58	3.065 (5)	111

Experimental details

Crystal data
Chemical formula	C₁₄H₁₅N₅O₂
M_r	285.31
Crystal system, space group	Orthorhombic, Pnma
Temperature (K)	298
a, b, c (Å)	14.921 (2), 6.7989 (11), 13.839 (2)
V (Å³)	1404.0 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.16 × 0.12 × 0.10

Data collection
Diffractometer	Bruker SMART CCD area-detector
Absorption correction	Multi-scan (SADABS; Sheldrick, 2008)
T_min, T_max	0.985, 0.991
No. of measured, independent and observed [I > 2σ(I)] reflections	7422, 1418, 1045
R_int	0.039
(sin θ/λ)_max (Å⁻¹)	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.065, 0.185, 1.07
No. of reflections	1418
No. of parameters	125
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.29

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1999) and PLATON (Spek, 2009), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···N4	0.93	2.37	3.021 (4)	127.3
C6—H6···N2	0.93	2.47	2.794 (5)	100.3
C11—H11···O1	0.98	2.13	2.727 (7)	117.4
C12—H12C···O2	0.96	2.58	3.065 (5)	111.3

Acknowledgements

We gratefully acknowledge financial support of this work by the National Basic Research Program of China (2003CB114400), the National Natural Science Foundation of China (20372023, 20102001), the Educational Commission of Hubei Province (grant Nos. B200624004, B20092412), the Shiyan Municipal Science and Technology Bureau (grant No. 20061835) and Hubei Medical University (grant Nos. 2007QDJ15, 2007ZQB19, 2007ZQB20).

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