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Acta Crystallogr Sect E Struct Rep Online. 2009 October 1; 65(Pt 10): o2583–o2584.
Published online 2009 September 30. doi:  10.1107/S160053680903788X
PMCID: PMC2970466

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

Abstract

In the title compound, C19H16ClN5O2, the triazolopyrimidine ring system is essentially planar, with a maximum displacement of 0.021 (4) Å, and forms dihedral angles of 1.09 (9) and 87.74 (9)° with the phenyl and benzene rings, respectively. Short intra­molecular C—H(...)O and C—H(...)N hydrogen-bonding inter­actions occur within the molecule. In the crystal structure, mol­ecules are linked by inter­molecular C—H(...)O hydrogen bonds into chains parallel to the b axis. In addition, π–π stacking inter­actions involving the triazole and pyrimidine rings of adjacent mol­ecules are observed, with centroid–centroid distances of 3.600 (3) Å.

Related literature

For the biological activity of 8-aza­guanine derivatives, see: Roblin et al. (1945 [triangle]); Ding et al. (2004 [triangle]); Mitchell et al. (1950 [triangle]); Levine et al. (1963 [triangle]); Montgomery et al. (1962 [triangle]); Yamamoto et al. (1967 [triangle]); Bariana (1971 [triangle]); Holland et al. (1975 [triangle]); For related structures, see: Ferguson et al. (1998 [triangle]); Li et al. (2004 [triangle]); Zhao, Xie et al. (2005 [triangle]); Zhao, Hu et al. (2005 [triangle]); Zhao, Wang & Ding (2005 [triangle]); Chen & Shi (2006 [triangle]); Maldonado et al. (2006 [triangle]); Xiao & Shi (2007 [triangle]); Wang et al. (2006 [triangle], 2008 [triangle]); Zeng et al. (2006 [triangle], 2009 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o2583-scheme1.jpg

Experimental

Crystal data

  • C19H16ClN5O2
  • M r = 381.82
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o2583-efi1.jpg
  • a = 16.8429 (3) Å
  • b = 11.7890 (2) Å
  • c = 18.8309 (3) Å
  • β = 91.737 (2)°
  • V = 3737.36 (11) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 0.23 mm−1
  • T = 298 K
  • 0.26 × 0.20 × 0.10 mm

Data collection

  • Bruker SMART CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.943, T max = 0.978
  • 10890 measured reflections
  • 3290 independent reflections
  • 2697 reflections with I > 2σ(I)
  • R int = 0.030

Refinement

  • R[F 2 > 2σ(F 2)] = 0.082
  • wR(F 2) = 0.188
  • S = 1.20
  • 3290 reflections
  • 246 parameters
  • H-atom parameters constrained
  • Δρmax = 0.35 e Å−3
  • Δρmin = −0.27 e Å−3

Data collection: SMART (Bruker, 2001 [triangle]); cell refinement: SAINT (Bruker, 2001 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053680903788X/rz2362sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053680903788X/rz2362Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

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 of China (grant Nos. B200624004, B20092412), the Shiyan Municipal Science and the Technology Bureau (grant No. 20061835) and Yunyang Medical College (grant Nos. 2007QDJ15, 2007ZQB19, 2007ZQB20).

supplementary crystallographic information

Comment

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

In recent years, we have been engaged in the preparation of the derivatives of 8-azaguanine via aza-Wittig reaction of /b-ethoxycarbonyl iminophosphorane with aromatic isocyanate (Zhao, Xie et al., 2005). As a continuation of our research for new biologically active heterocycles, the title compound was obtained from /b-ethoxycarbonyl iminophosphorane with alphalic isocyanate, and structurally characterized in this context.

In the title compound (Fig. 1), bond lengths and angles within the triazolopyrimidinone ring system are in good agreement with those observed for closely related structures (Zhao, Hu et al., 2005; Zhao, Wang & Ding, 2005). As reported for related compounds (Ferguson et al., 1998; Li et al., 2004; Maldonado et al., 2006; Zeng et al., 2006, 2009; Wang et al., 2006, 2008; Xiao et al., 2007; Chen & Shi, 2006), all ring atoms in the 1,2,3-triazolo[4,5-d]pyrimidine ring system are essentially coplanar (maximum deviation 0.021 (4) Å for atom C10), indicating that the moiety is a conjugate system. The dihedral angles it forms with the C1–C6 and C11–C16 phenyl and benzene rings are 1.09 (9) and 87.74 (9)°, respectively.

There exist two intramolecular C—H···O and C—H···N hydrogen bonding interactions (Table 1) stabilizing the molecular conformation. The crystal packing is stabilized by intermolecular C—H···O hydrogen bonds forming chains parallel to the b axis, and by π–π stacking interactions occurring between adjacent triazole and pyrimidine rings, with centroid-to-centroid distances of 3.600 (3) Å.

Experimental

To the solution of carbodiimide in CH2Cl2/CH3CN (1:4 v/v, 15 ml) prepared according to the literature method (Zeng et al., 2006), 4-chlorophenol (3 mmol) and excess K2CO3 were added, and the reaction mixture was stirred for 12 h. The solvent was removed under reduced pressure and the residue was recrystallized from EtOH to give the title compound (yield 92%; m.p. 459 K). Elemental analysis: calculated for C19H16ClN5O2: C, 59.77; H, 4.22; N, 18.34%. Found: C, 58.62; H, 4.48; N, 17.83%. Crystals suitable for single crystal X-ray diffraction analysis were obtained by slow evaporation of a hexane/dichloromethane (1:3 v/v) solution at room temperature.

Refinement

H atoms were placed at calculated positions and treated as riding atoms, with C—H = 0.93–0.98 Å, and Uiso(H) = 1.2Ueq(C) or 1.5Ueq(C) for methyl H atoms.

Figures

Fig. 1.
View of the molecule of showing the atom-labeling scheme. Displacement ellipsoids are drawn at 50% probability level. H-atoms are represented by circles of arbitrary size.

Crystal data

C19H16ClN5O2F(000) = 1584
Mr = 381.82Dx = 1.357 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 2541 reflections
a = 16.8429 (3) Åθ = 2.4–22.6°
b = 11.7890 (2) ŵ = 0.23 mm1
c = 18.8309 (3) ÅT = 298 K
β = 91.737 (2)°Block, colourless
V = 3737.36 (11) Å30.26 × 0.20 × 0.10 mm
Z = 8

Data collection

Bruker SMART CCD area-detector diffractometer3290 independent reflections
Radiation source: fine-focus sealed tube2697 reflections with I > 2σ(I)
graphiteRint = 0.030
[var phi] and ω scansθmax = 25.0°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −20→19
Tmin = 0.943, Tmax = 0.978k = −11→14
10890 measured reflectionsl = −22→22

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.082Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.188H-atom parameters constrained
S = 1.20w = 1/[σ2(Fo2) + (0.064P)2 + 5.7684P] where P = (Fo2 + 2Fc2)/3
3290 reflections(Δ/σ)max < 0.001
246 parametersΔρmax = 0.35 e Å3
0 restraintsΔρmin = −0.27 e Å3

Special details

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)

xyzUiso*/Ueq
C1−0.09358 (19)0.1023 (3)0.18512 (17)0.0439 (8)
C2−0.1566 (2)0.0468 (3)0.2139 (2)0.0642 (11)
H2−0.19840.08820.23190.077*
C3−0.1583 (3)−0.0702 (3)0.2161 (2)0.0737 (12)
H3−0.2009−0.10750.23600.088*
C4−0.0973 (3)−0.1310 (3)0.1891 (2)0.0689 (12)
H4−0.0982−0.20990.19030.083*
C5−0.0348 (3)−0.0757 (3)0.1601 (2)0.0673 (11)
H50.0067−0.11750.14170.081*
C6−0.0322 (2)0.0415 (3)0.1578 (2)0.0560 (10)
H60.01050.07850.13790.067*
C7−0.06815 (19)0.4035 (3)0.17494 (18)0.0453 (8)
C8−0.03822 (18)0.2986 (3)0.16141 (16)0.0397 (7)
C90.0704 (2)0.3664 (3)0.11400 (18)0.0462 (8)
C10−0.0258 (2)0.5037 (3)0.15489 (19)0.0510 (9)
C110.16545 (19)0.2430 (3)0.06917 (19)0.0476 (8)
C120.2136 (2)0.1916 (3)0.1182 (2)0.0666 (11)
H120.22990.22990.15920.080*
C130.2380 (3)0.0818 (4)0.1064 (2)0.0727 (12)
H130.27080.04490.13960.087*
C140.2136 (2)0.0283 (3)0.0458 (2)0.0618 (11)
C150.1683 (3)0.0821 (4)−0.0042 (2)0.0762 (13)
H150.15410.0454−0.04650.091*
C160.1431 (2)0.1920 (4)0.0077 (2)0.0687 (11)
H160.11140.2299−0.02600.082*
C170.1015 (2)0.5730 (3)0.1032 (2)0.0568 (10)
H170.15010.53780.08640.068*
C180.1260 (3)0.6448 (4)0.1659 (3)0.0860 (14)
H18A0.08160.68930.18040.129*
H18B0.16850.69430.15300.129*
H18C0.14360.59680.20440.129*
C190.0657 (3)0.6376 (4)0.0409 (3)0.0867 (14)
H19A0.05890.58750.00100.130*
H19B0.10050.69870.02870.130*
H19C0.01510.66780.05340.130*
Cl10.24101 (10)−0.11289 (10)0.03223 (8)0.1080 (6)
N1−0.09221 (15)0.2236 (2)0.18491 (14)0.0435 (7)
N2−0.15423 (17)0.2844 (3)0.21305 (17)0.0555 (8)
N3−0.13910 (18)0.3917 (3)0.20656 (17)0.0562 (8)
N40.03181 (15)0.2756 (2)0.13053 (15)0.0451 (7)
N50.04809 (16)0.4770 (2)0.12434 (15)0.0470 (7)
O1−0.04809 (17)0.6008 (2)0.16009 (17)0.0747 (9)
O20.14044 (14)0.35551 (19)0.08206 (14)0.0595 (7)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0430 (18)0.0388 (19)0.0495 (19)0.0002 (15)−0.0048 (15)−0.0037 (15)
C20.058 (2)0.051 (2)0.084 (3)−0.0023 (19)0.011 (2)−0.005 (2)
C30.084 (3)0.048 (2)0.091 (3)−0.017 (2)0.020 (3)−0.002 (2)
C40.095 (3)0.034 (2)0.077 (3)−0.002 (2)−0.004 (2)0.0014 (19)
C50.073 (3)0.042 (2)0.087 (3)0.013 (2)0.003 (2)−0.003 (2)
C60.053 (2)0.041 (2)0.074 (3)0.0024 (17)0.0059 (18)0.0014 (18)
C70.0420 (18)0.0389 (19)0.055 (2)0.0124 (15)0.0036 (15)−0.0041 (15)
C80.0373 (17)0.0401 (19)0.0417 (17)0.0047 (14)0.0002 (14)−0.0037 (14)
C90.0433 (19)0.042 (2)0.053 (2)0.0054 (15)0.0015 (15)0.0000 (16)
C100.055 (2)0.0335 (19)0.064 (2)0.0098 (16)−0.0051 (17)−0.0073 (16)
C110.0412 (18)0.041 (2)0.062 (2)0.0016 (15)0.0164 (16)0.0024 (17)
C120.075 (3)0.056 (2)0.069 (3)0.010 (2)−0.004 (2)−0.010 (2)
C130.081 (3)0.069 (3)0.069 (3)0.029 (2)0.000 (2)0.008 (2)
C140.066 (2)0.051 (2)0.070 (3)0.0115 (19)0.026 (2)0.001 (2)
C150.085 (3)0.074 (3)0.070 (3)0.008 (2)−0.001 (2)−0.025 (2)
C160.066 (3)0.070 (3)0.070 (3)0.024 (2)−0.006 (2)−0.006 (2)
C170.057 (2)0.0365 (19)0.077 (3)−0.0035 (17)0.0037 (19)0.0052 (18)
C180.091 (3)0.068 (3)0.098 (3)−0.026 (3)−0.012 (3)0.003 (3)
C190.098 (4)0.073 (3)0.089 (3)−0.009 (3)−0.005 (3)0.020 (3)
Cl10.1354 (12)0.0544 (8)0.1367 (12)0.0263 (7)0.0429 (10)−0.0117 (7)
N10.0396 (15)0.0378 (15)0.0533 (16)0.0061 (12)0.0041 (12)−0.0042 (12)
N20.0470 (17)0.0483 (19)0.072 (2)0.0101 (14)0.0133 (15)0.0009 (15)
N30.0543 (18)0.0444 (19)0.071 (2)0.0108 (14)0.0119 (15)−0.0055 (15)
N40.0434 (16)0.0315 (15)0.0606 (17)0.0021 (12)0.0067 (13)0.0009 (13)
N50.0459 (16)0.0328 (15)0.0624 (18)0.0066 (12)0.0040 (13)−0.0031 (13)
O10.0739 (19)0.0358 (15)0.116 (2)0.0105 (13)0.0193 (17)−0.0094 (14)
O20.0534 (15)0.0370 (14)0.0896 (19)0.0029 (11)0.0258 (13)0.0010 (12)

Geometric parameters (Å, °)

C1—C61.371 (5)C11—C121.353 (5)
C1—C21.372 (5)C11—O21.414 (4)
C1—N11.431 (4)C12—C131.378 (6)
C2—C31.380 (5)C12—H120.9300
C2—H20.9300C13—C141.357 (6)
C3—C41.365 (6)C13—H130.9300
C3—H30.9300C14—C151.352 (6)
C4—C51.366 (6)C14—Cl11.749 (4)
C4—H40.9300C15—C161.384 (6)
C5—C61.383 (5)C15—H150.9300
C5—H50.9300C16—H160.9300
C6—H60.9300C17—C181.500 (6)
C7—N31.358 (4)C17—N51.506 (4)
C7—C81.362 (4)C17—C191.509 (6)
C7—C101.436 (5)C17—H170.9800
C8—N11.352 (4)C18—H18A0.9600
C8—N41.358 (4)C18—H18B0.9600
C9—N41.296 (4)C18—H18C0.9600
C9—O21.346 (4)C19—H19A0.9600
C9—N51.372 (4)C19—H19B0.9600
C10—O11.210 (4)C19—H19C0.9600
C10—N51.422 (4)N1—N21.385 (4)
C11—C161.348 (5)N2—N31.297 (4)
C6—C1—C2120.0 (3)C12—C13—H13120.4
C6—C1—N1120.6 (3)C15—C14—C13121.2 (4)
C2—C1—N1119.4 (3)C15—C14—Cl1119.4 (3)
C1—C2—C3120.4 (4)C13—C14—Cl1119.4 (3)
C1—C2—H2119.8C14—C15—C16119.7 (4)
C3—C2—H2119.8C14—C15—H15120.2
C4—C3—C2119.8 (4)C16—C15—H15120.2
C4—C3—H3120.1C11—C16—C15118.6 (4)
C2—C3—H3120.1C11—C16—H16120.7
C3—C4—C5119.8 (4)C15—C16—H16120.7
C3—C4—H4120.1C18—C17—N5111.7 (3)
C5—C4—H4120.1C18—C17—C19114.9 (4)
C4—C5—C6120.9 (4)N5—C17—C19111.0 (3)
C4—C5—H5119.5C18—C17—H17106.2
C6—C5—H5119.5N5—C17—H17106.2
C1—C6—C5119.1 (4)C19—C17—H17106.2
C1—C6—H6120.5C17—C18—H18A109.5
C5—C6—H6120.5C17—C18—H18B109.5
N3—C7—C8109.0 (3)H18A—C18—H18B109.5
N3—C7—C10130.5 (3)C17—C18—H18C109.5
C8—C7—C10120.5 (3)H18A—C18—H18C109.5
N1—C8—N4127.7 (3)H18B—C18—H18C109.5
N1—C8—C7106.0 (3)C17—C19—H19A109.5
N4—C8—C7126.3 (3)C17—C19—H19B109.5
N4—C9—O2118.8 (3)H19A—C19—H19B109.5
N4—C9—N5127.5 (3)C17—C19—H19C109.5
O2—C9—N5113.7 (3)H19A—C19—H19C109.5
O1—C10—N5121.3 (3)H19B—C19—H19C109.5
O1—C10—C7126.9 (3)C8—N1—N2108.0 (3)
N5—C10—C7111.8 (3)C8—N1—C1131.7 (3)
C16—C11—C12122.1 (4)N2—N1—C1120.2 (3)
C16—C11—O2119.3 (3)N3—N2—N1108.4 (3)
C12—C11—O2118.6 (3)N2—N3—C7108.6 (3)
C11—C12—C13119.1 (4)C9—N4—C8112.7 (3)
C11—C12—H12120.4C9—N5—C10121.0 (3)
C13—C12—H12120.4C9—N5—C17120.5 (3)
C14—C13—C12119.2 (4)C10—N5—C17118.5 (3)
C14—C13—H13120.4C9—O2—C11115.8 (3)
C6—C1—C2—C30.7 (6)C6—C1—N1—C8−0.1 (5)
N1—C1—C2—C3−178.5 (4)C2—C1—N1—C8179.0 (3)
C1—C2—C3—C4−0.6 (7)C6—C1—N1—N2−179.6 (3)
C2—C3—C4—C50.2 (7)C2—C1—N1—N2−0.4 (5)
C3—C4—C5—C60.1 (7)C8—N1—N2—N30.4 (4)
C2—C1—C6—C5−0.4 (5)C1—N1—N2—N3−180.0 (3)
N1—C1—C6—C5178.7 (3)N1—N2—N3—C7−0.2 (4)
C4—C5—C6—C10.0 (6)C8—C7—N3—N2−0.1 (4)
N3—C7—C8—N10.3 (4)C10—C7—N3—N2178.8 (4)
C10—C7—C8—N1−178.6 (3)O2—C9—N4—C8−179.1 (3)
N3—C7—C8—N4−179.7 (3)N5—C9—N4—C80.0 (5)
C10—C7—C8—N41.4 (5)N1—C8—N4—C9−179.9 (3)
N3—C7—C10—O1−3.4 (6)C7—C8—N4—C90.1 (5)
C8—C7—C10—O1175.3 (4)N4—C9—N5—C10−1.6 (5)
N3—C7—C10—N5178.6 (3)O2—C9—N5—C10177.5 (3)
C8—C7—C10—N5−2.7 (5)N4—C9—N5—C17178.6 (3)
C16—C11—C12—C13−2.7 (6)O2—C9—N5—C17−2.3 (4)
O2—C11—C12—C13179.7 (3)O1—C10—N5—C9−175.3 (3)
C11—C12—C13—C140.4 (6)C7—C10—N5—C92.8 (4)
C12—C13—C14—C152.5 (7)O1—C10—N5—C174.4 (5)
C12—C13—C14—Cl1−177.4 (3)C7—C10—N5—C17−177.4 (3)
C13—C14—C15—C16−3.1 (7)C18—C17—N5—C9−119.2 (4)
Cl1—C14—C15—C16176.8 (3)C19—C17—N5—C9111.3 (4)
C12—C11—C16—C152.2 (6)C18—C17—N5—C1061.1 (4)
O2—C11—C16—C15179.8 (4)C19—C17—N5—C10−68.5 (4)
C14—C15—C16—C110.7 (7)N4—C9—O2—C110.2 (5)
N4—C8—N1—N2179.5 (3)N5—C9—O2—C11−179.0 (3)
C7—C8—N1—N2−0.5 (3)C16—C11—O2—C989.1 (4)
N4—C8—N1—C10.0 (6)C12—C11—O2—C9−93.2 (4)
C7—C8—N1—C1−180.0 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C17—H17···O20.982.162.679 (4)112
C6—H6···N40.932.363.013 (4)127
C4—H4···O1i0.932.463.317 (5)154

Symmetry codes: (i) x, y−1, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: RZ2362).

References

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