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ADDENDA AND ERRATA

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2-Benz­yl­oxy-1,2,4-triazolo[1,5-a]quinazolin-5(4H)-one

aDepartment of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia, and bDepartment of Chemistry, Institute of Pharmacy, University of Hamburg, Bundesstrasse 45, 20146 Hamburg, Germany
*Correspondence e-mail: abari@ksu.edu.sa

(Received 6 February 2011; accepted 25 June 2011; online 30 June 2011)

The title compound, C16H12N4O2, is a functionalized triazoloquinazoline with a substituted benz­yloxy group attached at the 2-position of a triazole spacer. The triazoloquinazoline fused-ring system is approximately planar (r.m.s. deviation = 0.016 Å) while the benzyl substituent is perpendicular to the ring system, making a dihedral angle of 65.29 (6)°. The phenyl ring of the benz­yloxy moiety is equally disordered over two sets of sites. A centrosymmetric N—H⋯N hydrogen bond connects mol­ecules into dimers.

Related literature

For the biological activity of related compounds, see: Francis et al. (1991[Francis, J. E., Cash, W. D., Barbaz, B. S., Bernard, P. S., Lovell, R. A., Mazzenga, G. C., Friedmann, R. C., Hyun, J. L., Braunwalder, A. F., Loo, P. S. & Bennett, D. A. (1991). J. Med. Chem. 34, 281-290.], 1998)[Francis, J. E., Cash, W. D., Psychoyos, S., Ghai, G., Wenk, P., Friedmann, R. C., Atkins, C., Warren, V., Furness, P., Hyun, T. L., Stone, G. A., Desai, M. & Williams, M. (1998). J. Med. Chem. 31, 1014-1020.]; Kim et al. (1998[Kim, Y.-C., De Zwart, M., Chang, L., Moro, S., Kuenzel, J., Melman, N., Jzerman, A. P. & Jacobson, K. A. (1998). J. Med. Chem. 41, 2835-2845.]); Geffken et al. (2008)[Geffken et al. (2008). Please give full reference.]. For related structures, see: Al-Salahi (2009[Al-Salahi, R. (2009). PhD dissertation, Hamburg University, Germany.]); Al-Salahi & Geffken (2010[Al-Salahi, R. & Geffken, D. (2010). Molecules, 15, 7016-7034.]); Berezank et al. (2008a[Berezank, J. F., Chan, D., Geffken, D., Hanagan, M. A,. Lepone, G. E., Pasteris, R. & S. Swan, T. (2008a). WO Patent 2008103357.],b[Berezank, J. F., Chan, D., Geffken, D., Hanagan, M. A,. Lepone, G. E., Pasteris, R. & S. Swan, T. (2008b). Chem. Abstr. 1042828.]); Ongini et al. (2001[Ongini, E., Monoppoli, A., Cacciari, B. & Baraldi, P. G. (2001). Farmaco, 56, 87-90.]).

[Scheme 1]

Experimental

Crystal data
  • C16H12N4O2

  • Mr = 292.30

  • Monoclinic, P 21 /n

  • a = 5.0319 (15) Å

  • b = 28.207 (9) Å

  • c = 9.408 (3) Å

  • β = 99.503 (5)°

  • V = 1317.0 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 153 K

  • 0.50 × 0.10 × 0.03 mm

Data collection
  • Bruker SMART APEX CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 1998[Bruker (1998). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.951, Tmax = 0.997

  • 8172 measured reflections

  • 2849 independent reflections

  • 1679 reflections with I > 2σ(I)

  • Rint = 0.053

Refinement
  • R[F2 > 2σ(F2)] = 0.047

  • wR(F2) = 0.098

  • S = 0.80

  • 2849 reflections

  • 236 parameters

  • 6 restraints

  • H-atom parameters constrained

  • Δρmax = 0.20 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯N4i 0.88 2.19 3.058 (2) 169
Symmetry code: (i) -x+1, -y+2, -z+1.

Data collection: SMART (Bruker, 1998[Bruker (1998). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1998[Bruker (1998). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Heterocycles with 1,2,4-triazoloquinazoline moiety have been shown to exhibit diverse biological activities. For example, the novel 2-(furan-2-yl)-[1,2,4]triazolo[1,5-c]quinazolin-5yl-amine is effective adenosine antagonist (Kim, et al., 1998) whereas the related compound 2-(4-fluoro-phenyl)-[1,2,4]triazolo[1,5-c]quinazolin-5-one was found to be benzodiazepine receptor antagonist (Francis, et al., 1988, 1991). In the continuation of our reesearch on triazoloquinazolines, we report herein the results of our study of cyclocondensation of dialkyl-N-cyanoimidocarbonates with hydrazinobenzoic acid. 2-alkoxy(arylkoxy)-[1,2,4]triazolo[1,5-a]quinazolin-5-ones is an excellent agent for controlling the plant growth diseases caused by fungal agents (Geffken, et al., 2008). The title compound, C16H12N4O2, (Fig. 1), consists of quinazoline (C1—C7, C16) and triazole (C8, N2—N4) rings substituted by the benzyl group (C9—C15). The phenyl ring of benzyloxy moiety is disodered over two locations where disordered atoms are in population 0.5:0.5. In the crystal structure, a pairs of intermolecular N—H···.N hydrogen bonds form centrosymmetric dimers (Table 1).

Related literature top

For the biological activity of related compounds, see: Francis et al. (1991, 1998); Kim et al. (1998); Geffken et al. (2008). For related literature [on what subject?, see: Al-Salahi (2009); Al-Salahi & Geffken (2010); Berezank et al. (2008a, 2008b); Ongini et al. (2001).

Experimental top

2-Hydrazinobenzoic acid (10 mmol) was added in portion to a stirred solution of dibenzyl-N-cyanoimidocarbonate (10 mmol) in ethanol (20 mL) at 273 K. Afterwards triethylamine (30 mmol) was added dropwise over a period of 30 min. After the addition was completed, the reaction mixture was left to stirr overnight at room temperature. Acidification of the mixture was performed by conc. HCl under ice cooling followed by refluxing for 1–2 h. After cooling, the mixture was poured into ice/water, the resulting solid was filtered, washed with water and dried. Recrystallisation from tetrahydrofuran (THF) yielded 2-benzyloxy-4H-[1,2,4]triazolo[1,5-a]quinazolin-5-one as colourless crystals.

Refinement top

Data corrected for absorption using SADABS (Bruker, 1998) and structure solved by direct methods. All nonhydrogen atoms refined as anisotropic by Fourier full matrix least squares. All H atoms were positioned geometrically and refined using a riding model, with C–H = 0.93–0.99 Å. The displacement parameters are Uiso(H) = Ueq(C) where x = 1.2 or 1.5. The phenyl ring of benzyloxy moiety is disordered over the two sites with population 0.5 ofatoms in each orientation.

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: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. : The molecular structure of the title compound showing 50% probability displacement ellipsoids for non-H atoms and the atom-numbering scheme.
2-Benzyloxy-1,2,4-triazolo[1,5-a]quinazolin-5(4H)-one top
Crystal data top
C16H12N4O2Z = 4
Mr = 292.30F(000) = 608
Monoclinic, P21/nDx = 1.474 Mg m3
a = 5.0319 (15) ÅMo Kα radiation, λ = 0.71073 Å
b = 28.207 (9) ŵ = 0.10 mm1
c = 9.408 (3) ÅT = 153 K
β = 99.503 (5)°Needle, colourless
V = 1317.0 (7) Å30.50 × 0.10 × 0.03 mm
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
2849 independent reflections
Radiation source: fine-focus sealed tube1679 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.053
ω scansθmax = 27.0°, θmin = 2.9°
Absorption correction: multi-scan
(SADABS; Bruker, 1998)
h = 66
Tmin = 0.951, Tmax = 0.997k = 2535
8172 measured reflectionsl = 1211
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.098H-atom parameters constrained
S = 0.80 w = 1/[σ2(Fo2) + (0.0347P)2 + 0.4968P]
where P = (Fo2 + 2Fc2)/3
2849 reflections(Δ/σ)max = 0.005
236 parametersΔρmax = 0.20 e Å3
6 restraintsΔρmin = 0.20 e Å3
Crystal data top
C16H12N4O2V = 1317.0 (7) Å3
Mr = 292.30Z = 4
Monoclinic, P21/nMo Kα radiation
a = 5.0319 (15) ŵ = 0.10 mm1
b = 28.207 (9) ÅT = 153 K
c = 9.408 (3) Å0.50 × 0.10 × 0.03 mm
β = 99.503 (5)°
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
2849 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 1998)
1679 reflections with I > 2σ(I)
Tmin = 0.951, Tmax = 0.997Rint = 0.053
8172 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0476 restraints
wR(F2) = 0.098H-atom parameters constrained
S = 0.80Δρmax = 0.20 e Å3
2849 reflectionsΔρmin = 0.20 e Å3
236 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
xyzUiso*/UeqOcc. (<1)
O10.8828 (3)1.12152 (5)0.45128 (14)0.0270 (4)
O20.8556 (3)0.91207 (5)0.83235 (14)0.0245 (4)
N10.7916 (3)1.04986 (6)0.54486 (16)0.0209 (4)
H10.64601.04650.47960.025*
N21.0822 (3)1.01884 (6)0.74430 (16)0.0194 (4)
N31.1110 (3)0.97886 (6)0.83206 (17)0.0231 (4)
N40.7304 (3)0.97406 (6)0.65836 (16)0.0197 (4)
C11.2541 (4)1.05801 (7)0.7576 (2)0.0195 (5)
C21.4809 (4)1.06091 (7)0.8647 (2)0.0237 (5)
H21.52561.03590.93210.028*
C31.6386 (4)1.10113 (7)0.8700 (2)0.0276 (5)
H31.79251.10390.94300.033*
C41.5772 (4)1.13772 (8)0.7708 (2)0.0287 (5)
H41.68911.16500.77620.034*
C51.3524 (4)1.13430 (7)0.6640 (2)0.0236 (5)
H51.31051.15920.59620.028*
C61.1870 (4)1.09411 (7)0.6560 (2)0.0196 (5)
C70.9465 (4)1.09086 (7)0.5424 (2)0.0203 (5)
C80.8573 (4)1.01485 (7)0.64452 (19)0.0180 (4)
C90.8959 (4)0.95440 (7)0.7751 (2)0.0193 (5)
C100.6230 (4)0.88574 (7)0.7619 (2)0.0256 (5)
H10A0.62380.88430.65680.031*
H10B0.45530.90170.77790.031*
C110.6348 (4)0.83661 (7)0.8236 (2)0.0225 (5)0.496 (2)
C120.5451 (8)0.79726 (15)0.7427 (5)0.0272 (11)0.496 (2)
H120.48050.80180.64290.033*0.496 (2)
C130.5427 (9)0.75163 (15)0.7968 (5)0.0300 (12)0.496 (2)
H130.47600.72610.73520.036*0.496 (2)
C140.6311 (5)0.74409 (8)0.9305 (3)0.0357 (6)0.496 (2)
H140.62460.71260.96580.043*0.496 (2)
C150.7393 (9)0.78049 (16)1.0299 (5)0.0313 (12)0.496 (2)
H150.80710.77371.12810.038*0.496 (2)
C160.7399 (8)0.82635 (15)0.9751 (4)0.0228 (10)0.496 (2)
H160.80990.85151.03730.027*0.496 (2)
C11'0.6348 (4)0.83661 (7)0.8236 (2)0.0225 (5)0.504 (2)
C12'0.3903 (8)0.81776 (14)0.8448 (4)0.0242 (11)0.504 (2)
H12'0.22900.83580.82440.029*0.504 (2)
C13'0.3880 (9)0.77136 (15)0.8972 (4)0.0281 (11)0.504 (2)
H13'0.22190.75760.91110.034*0.504 (2)
C14'0.6311 (5)0.74409 (8)0.9305 (3)0.0357 (6)0.504 (2)
H14'0.63570.71370.97450.043*0.504 (2)
C15'0.8587 (10)0.76532 (16)0.8936 (5)0.0408 (14)0.504 (2)
H15'1.02080.74740.90420.049*0.504 (2)
C16'0.8615 (9)0.81179 (16)0.8417 (5)0.0357 (13)0.504 (2)
H16'1.02290.82530.81980.043*0.504 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0252 (8)0.0249 (9)0.0296 (8)0.0033 (7)0.0001 (6)0.0086 (7)
O20.0239 (8)0.0186 (8)0.0285 (8)0.0063 (7)0.0031 (6)0.0045 (6)
N10.0183 (9)0.0213 (10)0.0217 (9)0.0006 (8)0.0007 (7)0.0038 (7)
N20.0187 (9)0.0168 (9)0.0218 (9)0.0002 (8)0.0001 (7)0.0019 (7)
N30.0256 (10)0.0168 (9)0.0259 (9)0.0018 (8)0.0013 (7)0.0034 (8)
N40.0186 (9)0.0174 (9)0.0224 (9)0.0001 (8)0.0017 (7)0.0013 (7)
C10.0188 (11)0.0164 (11)0.0240 (10)0.0016 (9)0.0056 (8)0.0040 (9)
C20.0236 (12)0.0235 (12)0.0234 (11)0.0021 (10)0.0019 (9)0.0018 (9)
C30.0264 (13)0.0249 (12)0.0287 (11)0.0038 (10)0.0034 (9)0.0035 (10)
C40.0268 (13)0.0239 (12)0.0341 (12)0.0074 (10)0.0009 (10)0.0001 (10)
C50.0278 (12)0.0174 (11)0.0258 (11)0.0013 (10)0.0050 (9)0.0007 (9)
C60.0189 (11)0.0188 (11)0.0217 (10)0.0031 (9)0.0055 (8)0.0017 (9)
C70.0193 (11)0.0190 (12)0.0237 (11)0.0020 (9)0.0071 (8)0.0000 (9)
C80.0168 (11)0.0185 (11)0.0194 (10)0.0022 (9)0.0050 (8)0.0022 (9)
C90.0187 (11)0.0168 (11)0.0221 (10)0.0006 (9)0.0022 (8)0.0003 (9)
C100.0206 (12)0.0254 (13)0.0296 (11)0.0021 (10)0.0007 (9)0.0018 (9)
C110.0184 (12)0.0220 (12)0.0280 (11)0.0004 (10)0.0071 (8)0.0021 (9)
C120.027 (3)0.023 (3)0.030 (2)0.003 (2)0.0003 (19)0.0025 (19)
C130.027 (3)0.020 (3)0.041 (3)0.002 (2)0.001 (2)0.000 (2)
C140.0316 (15)0.0226 (13)0.0535 (16)0.0040 (11)0.0088 (12)0.0055 (11)
C150.036 (3)0.029 (3)0.029 (2)0.001 (2)0.007 (2)0.006 (2)
C160.022 (2)0.022 (2)0.025 (2)0.0017 (19)0.0085 (18)0.0003 (18)
C11'0.0184 (12)0.0220 (12)0.0280 (11)0.0004 (10)0.0071 (8)0.0021 (9)
C12'0.019 (2)0.023 (3)0.031 (2)0.0005 (19)0.0057 (18)0.0009 (19)
C13'0.030 (3)0.026 (3)0.029 (2)0.005 (2)0.0084 (19)0.002 (2)
C14'0.0316 (15)0.0226 (13)0.0535 (16)0.0040 (11)0.0088 (12)0.0055 (11)
C15'0.028 (3)0.027 (3)0.066 (3)0.003 (2)0.002 (2)0.008 (2)
C16'0.020 (3)0.028 (3)0.059 (3)0.001 (2)0.008 (2)0.011 (2)
Geometric parameters (Å, º) top
O1—C71.223 (2)C6—C71.479 (3)
O2—C91.339 (2)C10—C111.500 (3)
O2—C101.450 (2)C10—H10A0.9900
N1—C81.364 (2)C10—H10B0.9900
N1—C71.397 (2)C11—C121.379 (5)
N1—H10.8800C11—C161.465 (4)
N2—C81.351 (2)C12—C131.385 (6)
N2—N31.391 (2)C12—H120.9500
N2—C11.396 (2)C13—C141.281 (5)
N3—C91.320 (2)C13—H130.9500
N4—C81.333 (2)C14—C151.435 (5)
N4—C91.380 (2)C14—H140.9500
C1—C21.394 (3)C15—C161.393 (6)
C1—C61.399 (3)C15—H150.9500
C2—C31.381 (3)C16—H160.9500
C2—H20.9500C12'—C13'1.399 (6)
C3—C41.392 (3)C12'—H12'0.9500
C3—H30.9500C13'—H13'0.9500
C4—C51.387 (3)C15'—C16'1.400 (6)
C4—H40.9500C15'—H15'0.9500
C5—C61.401 (3)C16'—H16'0.9500
C5—H50.9500
C9—O2—C10115.94 (15)N2—C8—N1119.84 (18)
C8—N1—C7122.56 (16)N3—C9—O2118.13 (17)
C8—N1—H1118.7N3—C9—N4117.35 (18)
C7—N1—H1118.7O2—C9—N4124.51 (17)
C8—N2—N3109.78 (16)O2—C10—C11108.60 (16)
C8—N2—C1124.32 (16)O2—C10—H10A110.0
N3—N2—C1125.89 (16)C11—C10—H10A110.0
C9—N3—N2100.65 (15)O2—C10—H10B110.0
C8—N4—C9100.89 (16)C11—C10—H10B110.0
C2—C1—N2122.16 (18)H10A—C10—H10B108.3
C2—C1—C6121.80 (19)C12—C11—C16114.3 (3)
N2—C1—C6116.03 (17)C12—C11—C10122.8 (2)
C3—C2—C1118.12 (19)C16—C11—C10122.9 (2)
C3—C2—H2120.9C11—C12—C13124.5 (4)
C1—C2—H2120.9C11—C12—H12117.7
C2—C3—C4121.51 (19)C13—C12—H12117.7
C2—C3—H3119.2C14—C13—C12119.5 (4)
C4—C3—H3119.2C14—C13—H13120.2
C5—C4—C3119.9 (2)C12—C13—H13120.2
C5—C4—H4120.1C13—C14—C15123.7 (3)
C3—C4—H4120.1C13—C14—H14118.2
C4—C5—C6120.09 (19)C15—C14—H14118.2
C4—C5—H5120.0C16—C15—C14116.6 (4)
C6—C5—H5120.0C16—C15—H15121.7
C1—C6—C5118.57 (18)C14—C15—H15121.7
C1—C6—C7121.65 (18)C15—C16—C11121.4 (4)
C5—C6—C7119.78 (18)C15—C16—H16119.3
O1—C7—N1120.98 (18)C11—C16—H16119.3
O1—C7—C6123.46 (19)C13'—C12'—H12'121.0
N1—C7—C6115.55 (17)C12'—C13'—H13'119.3
N4—C8—N2111.34 (16)C16'—C15'—H15'118.4
N4—C8—N1128.80 (17)C15'—C16'—H16'120.6
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···N4i0.882.193.058 (2)169
Symmetry code: (i) x+1, y+2, z+1.

Experimental details

Crystal data
Chemical formulaC16H12N4O2
Mr292.30
Crystal system, space groupMonoclinic, P21/n
Temperature (K)153
a, b, c (Å)5.0319 (15), 28.207 (9), 9.408 (3)
β (°) 99.503 (5)
V3)1317.0 (7)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.50 × 0.10 × 0.03
Data collection
DiffractometerBruker SMART APEX CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 1998)
Tmin, Tmax0.951, 0.997
No. of measured, independent and
observed [I > 2σ(I)] reflections
8172, 2849, 1679
Rint0.053
(sin θ/λ)max1)0.639
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.098, 0.80
No. of reflections2849
No. of parameters236
No. of restraints6
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.20, 0.20

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

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···N4i0.882.193.058 (2)169
Symmetry code: (i) x+1, y+2, z+1.
 

Acknowledgements

We wish to express our gratitude to the Department of Chemistry, X-ray Crystallography Division of Hamburg University, and Dr Rudi Seidel, Max-Planck-Institut für Kohlenforschung, Germany, for valuable help in the preparation of the X-ray crystal structure.

References

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