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

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].

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.065
• wR factor = 0.185
• Data-to-parameter ratio = 11.3

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         N3
PLAT340_ALERT_3_C Low Bond Precision on  C-C Bonds (x 1000) Ang ..          5
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          2
PLAT922_ALERT_1_C wR2 * 100.0 in the CIF and FCF Differ by .......       0.15

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

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

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).

S2. Experimental

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.

S3. Refinement

All H atoms attached to C atoms and N atom were fixed geometrically and treated as riding with C—H = 0.98 Å (methine), 0.96 Å (methyl) or 0.93 Å (aromatic) with U_iso(H) = 1.2U_eq(C) or U_iso(H) = 1.5U_eq(C_methyl).

Computing details

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

	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

Crystal data

C14H15N5O2	F(000) = 600
Mr = 285.31	Dx = 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) Å^3	Block, colourless
Z = 4	0.16 × 0.12 × 0.10 mm

Data collection

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

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.065	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.185	H-atom parameters constrained
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0883P)^2 + 0.4734P] where P = (Fo^2 + 2Fc^2)/3
1418 reflections	(Δ/σ)max < 0.001
125 parameters	Δρmax = 0.23 e Å^−3
0 restraints	Δρmin = −0.29 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq	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 (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
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)

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—C12^i	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)	C12^i—C11—C12	122.8 (5)
C6—C1—N1	120.0 (3)	C12^i—C11—N5	113.2 (2)
C3—C2—C1	119.4 (3)	C12—C11—N5	113.2 (2)
C3—C2—H2	120.3	C12^i—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)

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