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ISSN: 2056-9890

2-Methyl-3-(2-methyl­phen­yl)-7-nitro­quinazolin-4(3H)-one

aDepartment of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia, bDepartment of Organic Chemistry, Faculty of Pharmacy, Al-Azhar University, Cairo 11884, Egypt, cDepartment of Medicinal Chemistry, Faculty of Pharmacy, University of Mansoura, Mansoura 35516, Egypt, dDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, and eChemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203 Jeddah, Saudi Arabia
*Correspondence e-mail: edward.tiekink@gmail.com

(Received 18 February 2012; accepted 18 February 2012; online 29 February 2012)

In the title methaqua­lone analogue, C16H13N3O3, the 2-tolyl group is almost orthogonal [dihedral angle = 85.20 (5)°] to the fused ring system (r.m.s. deviation of fitted non-H atoms = 0.029 Å). In the crystal, twofold symmetry generates two-mol­ecule aggregates linked by C—H⋯O and ππ inter­actions [ring centroid–centroid distance = 3.4967 (6) Å].

Related literature

For recent studies on synthesis, drug discovery and crystal structures of quinazoline-4(3H)-one derivatives, see: El-Azab et al. (2010[El-Azab, A. S., Al-Omar, M. A., Abdel-Aziz, A. A.-M., Abdel-Aziz, N. I., El-Sayed, M. A.-A., Aleisa, A. M., Sayed-Ahmed, M. M. & Abdel-Hamide, S. G. (2010). Eur. J. Med. Chem. 45, 4188-4198.], 2012[El-Azab, A. S. & ElTahir, K. H. (2012). Bioorg. Med. Chem. Lett. 22, 327-333.]). For the anti-convulsant activity of the title methaqua­lone analogue, see: El-Azab et al. (2011[El-Azab, A. S., ElTahir, K. H. & Attia, S. M. (2011). Monatsh. Chem. 142, 837-848.]). For a related structure, see: Stephenson et al. (2011[Stephenson, K. A., Wilson, A. A., Houle, S. & Vasdev, N. (2011). Bioorg. Med. Chem. Lett. 21, 5506-5509.]).

[Scheme 1]

Experimental

Crystal data
  • C16H13N3O3

  • Mr = 295.29

  • Monoclinic, C 2/c

  • a = 14.4614 (5) Å

  • b = 16.5383 (4) Å

  • c = 12.9968 (4) Å

  • β = 119.072 (4)°

  • V = 2716.78 (14) Å3

  • Z = 8

  • Cu Kα radiation

  • μ = 0.85 mm−1

  • T = 100 K

  • 0.25 × 0.25 × 0.25 mm

Data collection
  • Agilent SuperNova Dual diffractometer with an Atlas detector

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, Oxfordshire, England.]) Tmin = 0.967, Tmax = 0.998

  • 5450 measured reflections

  • 2783 independent reflections

  • 2570 reflections with I > 2σ(I)

  • Rint = 0.013

Refinement
  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.099

  • S = 1.02

  • 2783 reflections

  • 201 parameters

  • H-atom parameters constrained

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.24 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C11—H11⋯O1i 0.95 2.54 3.4530 (15) 161
Symmetry code: (i) [-x+1, y, -z+{\script{1\over 2}}].

Data collection: CrysAlis PRO (Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, Oxfordshire, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

The title methaqualone analogue, 2-methyl-7-nitro-3-o-tolylquinazolin-4(3H)-one (I), has been investigated previously for its anti-convulsant activity (El-Azab et al., 2012) as quinazoline-4(3H)-one derivatives are known for their various biological activities (El-Azab et al., 2011, 2010). Herein, the crystal and molecular structure of (I) is described. A related structure with a similar conformation has been reported recently (Stephenson et al., 2011).

The ten atoms comprising the fused ring system in (I), Fig. 1, are almost co-planar with the r.m.s. deviation for the non-hydrogen atoms being 0.029 Å. The 2-tolyl group is approximately orthogonal to this plane, forming a dihedral angle of 85.20 (5) °. The nitro group is almost co-planar with the ring to which it is connected as seen in the value of the O2—N3—C3—C2 torsion angle of 179.07 (10)°.

The main feature of the crystal packing is the formation of two molecule aggregates sustained by C—H···O, Table 1, and ππ interactions, Fig. 2. The ππ interactions occur between (C1–C6) rings, i.e. the C6 group within the fused ring system, with a ring centroid-to-centroid distance of 3.4967 (6) Å [symmetry operation: 1 - x, y, 1/2 - z]. There are no specific intermolecular interactions between the two-molecule aggregates [generated by 2-fold symmetry]. They assemble into layers in the bc plane, Fig. 3, and these stack along the a axis, Fig. 4.

Related literature top

For recent studies on synthesis, drug discovery and crystal structures of quinazoline-4(3H)-one derivatives, see: El-Azab et al. (2012, 2010). For the anti-convulsant activity of the title methaqualone analogue, see: El-Azab et al. (2011). For a related structure, see: Stephenson et al. (2011).

Experimental top

4-Nitroanthranilic acid (1.82 g, 10 mmol) was refluxed with acetic anhydride (20 ml) for 3 h. The reaction mixture was cooled, filtered, washed with petroleum ether, and dried to yield 2-methyl-7-nitro-4H-3,1-benzoxazin-4-one as an a solid compound. This was refluxed with o-toludine (1.18 g, 11 mmol) in pyridine (30 ml) for 8 h. The reaction mixture was cooled, the solvent was removed under reduced pressure and the residue was triturated with water and filtered. The solid obtained was dried, chromatographed with CHCl3 and recrystallized from its EtOH solution as colourless cubes.

Refinement top

Carbon-bound H-atoms were placed in calculated positions [C—H = 0.95 to 0.98 Å, Uiso(H) = 1.2 to 1.5Ueq(C)] and were included in the refinement in the riding model approximation.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing displacement ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. A view of the two-molecular aggregate in (I) sustained by C—H···O and ππ interactions shown as orange and purple dashed lines, respectively.
[Figure 3] Fig. 3. A view of the assembly of two-molecule aggregates in the bc plane in (I). The C—H···O and ππ interactions are shown as orange and purple dashed lines, respectively.
[Figure 4] Fig. 4. A view in projection down the a axis of the unit-cell contents of (I). The C—H···O and ππ interactions are shown as orange and purple dashed lines, respectively.
2-Methyl-3-(2-methylphenyl)-7-nitroquinazolin-4(3H)-one top
Crystal data top
C16H13N3O3F(000) = 1232
Mr = 295.29Dx = 1.444 Mg m3
Monoclinic, C2/cCu Kα radiation, λ = 1.54184 Å
Hall symbol: -C 2ycCell parameters from 3546 reflections
a = 14.4614 (5) Åθ = 3.9–76.4°
b = 16.5383 (4) ŵ = 0.85 mm1
c = 12.9968 (4) ÅT = 100 K
β = 119.072 (4)°Cube, colourless
V = 2716.78 (14) Å30.25 × 0.25 × 0.25 mm
Z = 8
Data collection top
Agilent SuperNova Dual
diffractometer with an Atlas detector
2783 independent reflections
Radiation source: SuperNova (Cu) X-ray Source2570 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.013
Detector resolution: 10.4041 pixels mm-1θmax = 76.6°, θmin = 4.4°
ω scanh = 1817
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)
k = 2018
Tmin = 0.967, Tmax = 0.998l = 1016
5450 measured reflections
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)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.099H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0566P)2 + 1.6285P]
where P = (Fo2 + 2Fc2)/3
2783 reflections(Δ/σ)max < 0.001
201 parametersΔρmax = 0.24 e Å3
0 restraintsΔρmin = 0.24 e Å3
Crystal data top
C16H13N3O3V = 2716.78 (14) Å3
Mr = 295.29Z = 8
Monoclinic, C2/cCu Kα radiation
a = 14.4614 (5) ŵ = 0.85 mm1
b = 16.5383 (4) ÅT = 100 K
c = 12.9968 (4) Å0.25 × 0.25 × 0.25 mm
β = 119.072 (4)°
Data collection top
Agilent SuperNova Dual
diffractometer with an Atlas detector
2783 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)
2570 reflections with I > 2σ(I)
Tmin = 0.967, Tmax = 0.998Rint = 0.013
5450 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.099H-atom parameters constrained
S = 1.02Δρmax = 0.24 e Å3
2783 reflectionsΔρmin = 0.24 e Å3
201 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*/Ueq
O10.59490 (6)0.19268 (5)0.43782 (7)0.0250 (2)
O20.65765 (7)0.61062 (5)0.45232 (9)0.0338 (2)
O30.48735 (7)0.62439 (5)0.36278 (8)0.0330 (2)
N10.41702 (7)0.21605 (6)0.35394 (8)0.0201 (2)
N20.34237 (7)0.34733 (6)0.30533 (8)0.0217 (2)
N30.56777 (8)0.58294 (6)0.40625 (9)0.0247 (2)
C10.44368 (9)0.37812 (7)0.35225 (9)0.0196 (2)
C20.45504 (9)0.46277 (7)0.35369 (9)0.0208 (2)
H20.39490.49720.32100.025*
C30.55556 (9)0.49398 (7)0.40369 (10)0.0214 (2)
C40.64664 (9)0.44647 (7)0.45173 (10)0.0225 (2)
H40.71480.47070.48590.027*
C50.63564 (9)0.36354 (7)0.44855 (9)0.0215 (2)
H50.69640.32980.47950.026*
C60.53454 (9)0.32924 (7)0.39953 (9)0.0195 (2)
C70.52197 (8)0.24124 (7)0.39980 (9)0.0200 (2)
C80.33210 (8)0.26981 (7)0.30874 (9)0.0211 (2)
C90.22363 (9)0.23499 (7)0.26233 (11)0.0273 (3)
H9A0.17150.27880.23560.041*
H9B0.21990.20440.32480.041*
H9C0.20840.19890.19620.041*
C100.39793 (8)0.13076 (7)0.36267 (10)0.0207 (2)
C110.37329 (9)0.08065 (7)0.26703 (10)0.0236 (2)
H110.37320.10110.19870.028*
C120.34882 (9)0.00019 (7)0.27286 (11)0.0252 (3)
H120.32910.03450.20710.030*
C130.35326 (9)0.02949 (7)0.37522 (11)0.0242 (3)
H130.33710.08460.37980.029*
C140.38125 (9)0.02132 (7)0.47070 (10)0.0232 (2)
H140.38630.00010.54110.028*
C150.40209 (8)0.10313 (7)0.46597 (10)0.0214 (2)
C160.42659 (10)0.15867 (8)0.56764 (10)0.0270 (3)
H16A0.49050.18990.58660.040*
H16B0.43810.12660.63630.040*
H16C0.36710.19570.54630.040*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0190 (4)0.0239 (4)0.0292 (4)0.0027 (3)0.0094 (3)0.0001 (3)
O20.0311 (5)0.0281 (5)0.0405 (5)0.0096 (4)0.0161 (4)0.0045 (4)
O30.0324 (5)0.0247 (4)0.0405 (5)0.0026 (4)0.0166 (4)0.0039 (4)
N10.0172 (5)0.0203 (5)0.0208 (5)0.0004 (3)0.0077 (4)0.0000 (3)
N20.0180 (4)0.0233 (5)0.0217 (5)0.0007 (4)0.0080 (4)0.0022 (4)
N30.0284 (5)0.0241 (5)0.0238 (5)0.0033 (4)0.0143 (4)0.0008 (4)
C10.0190 (5)0.0242 (5)0.0158 (5)0.0000 (4)0.0087 (4)0.0003 (4)
C20.0213 (5)0.0237 (6)0.0182 (5)0.0017 (4)0.0101 (4)0.0015 (4)
C30.0265 (6)0.0218 (5)0.0183 (5)0.0021 (4)0.0126 (4)0.0007 (4)
C40.0195 (5)0.0275 (6)0.0194 (5)0.0046 (4)0.0088 (4)0.0023 (4)
C50.0185 (5)0.0262 (6)0.0187 (5)0.0003 (4)0.0082 (4)0.0005 (4)
C60.0194 (5)0.0230 (5)0.0160 (5)0.0002 (4)0.0087 (4)0.0005 (4)
C70.0170 (5)0.0245 (6)0.0173 (5)0.0003 (4)0.0075 (4)0.0010 (4)
C80.0171 (5)0.0251 (5)0.0188 (5)0.0004 (4)0.0069 (4)0.0014 (4)
C90.0175 (5)0.0265 (6)0.0326 (6)0.0001 (4)0.0080 (5)0.0038 (5)
C100.0161 (5)0.0208 (5)0.0226 (5)0.0002 (4)0.0073 (4)0.0006 (4)
C110.0216 (5)0.0262 (6)0.0217 (5)0.0001 (4)0.0094 (4)0.0001 (4)
C120.0223 (6)0.0252 (6)0.0260 (6)0.0021 (4)0.0101 (5)0.0049 (4)
C130.0182 (5)0.0221 (5)0.0291 (6)0.0014 (4)0.0090 (5)0.0007 (4)
C140.0164 (5)0.0269 (6)0.0240 (6)0.0010 (4)0.0081 (4)0.0030 (4)
C150.0145 (5)0.0252 (6)0.0219 (5)0.0002 (4)0.0068 (4)0.0010 (4)
C160.0270 (6)0.0301 (6)0.0227 (6)0.0035 (5)0.0112 (5)0.0025 (5)
Geometric parameters (Å, º) top
O1—C71.2227 (14)C8—C91.4955 (15)
O2—N31.2253 (13)C9—H9A0.9800
O3—N31.2261 (14)C9—H9B0.9800
N1—C81.3938 (14)C9—H9C0.9800
N1—C71.3976 (14)C10—C111.3887 (16)
N1—C101.4522 (14)C10—C151.3915 (16)
N2—C81.2939 (15)C11—C121.3885 (16)
N2—C11.3818 (14)C11—H110.9500
N3—C31.4803 (14)C12—C131.3899 (17)
C1—C61.4046 (15)C12—H120.9500
C1—C21.4086 (15)C13—C141.3863 (17)
C2—C31.3724 (16)C13—H130.9500
C2—H20.9500C14—C151.3939 (16)
C3—C41.3939 (16)C14—H140.9500
C4—C51.3790 (16)C15—C161.5035 (15)
C4—H40.9500C16—H16A0.9800
C5—C61.4000 (15)C16—H16B0.9800
C5—H50.9500C16—H16C0.9800
C6—C71.4670 (15)
C8—N1—C7122.78 (9)C8—C9—H9A109.5
C8—N1—C10119.37 (9)C8—C9—H9B109.5
C7—N1—C10117.68 (9)H9A—C9—H9B109.5
C8—N2—C1117.70 (9)C8—C9—H9C109.5
O2—N3—O3124.04 (10)H9A—C9—H9C109.5
O2—N3—C3117.96 (10)H9B—C9—H9C109.5
O3—N3—C3117.99 (10)C11—C10—C15122.65 (11)
N2—C1—C6123.15 (10)C11—C10—N1119.05 (10)
N2—C1—C2117.64 (10)C15—C10—N1118.27 (10)
C6—C1—C2119.20 (10)C12—C11—C10118.98 (11)
C3—C2—C1118.02 (10)C12—C11—H11120.5
C3—C2—H2121.0C10—C11—H11120.5
C1—C2—H2121.0C11—C12—C13119.74 (11)
C2—C3—C4123.58 (10)C11—C12—H12120.1
C2—C3—N3118.14 (10)C13—C12—H12120.1
C4—C3—N3118.28 (10)C14—C13—C12120.02 (11)
C5—C4—C3118.49 (10)C14—C13—H13120.0
C5—C4—H4120.8C12—C13—H13120.0
C3—C4—H4120.8C13—C14—C15121.61 (11)
C4—C5—C6119.76 (10)C13—C14—H14119.2
C4—C5—H5120.1C15—C14—H14119.2
C6—C5—H5120.1C10—C15—C14116.90 (10)
C5—C6—C1120.93 (10)C10—C15—C16121.90 (10)
C5—C6—C7120.27 (10)C14—C15—C16121.19 (10)
C1—C6—C7118.77 (10)C15—C16—H16A109.5
O1—C7—N1121.42 (10)C15—C16—H16B109.5
O1—C7—C6124.68 (10)H16A—C16—H16B109.5
N1—C7—C6113.88 (9)C15—C16—H16C109.5
N2—C8—N1123.66 (10)H16A—C16—H16C109.5
N2—C8—C9118.89 (10)H16B—C16—H16C109.5
N1—C8—C9117.45 (10)
C8—N2—C1—C62.02 (16)C1—C6—C7—O1179.56 (10)
C8—N2—C1—C2176.98 (10)C5—C6—C7—N1176.62 (9)
N2—C1—C2—C3177.87 (10)C1—C6—C7—N11.68 (14)
C6—C1—C2—C31.17 (15)C1—N2—C8—N11.83 (16)
C1—C2—C3—C40.77 (17)C1—N2—C8—C9177.94 (10)
C1—C2—C3—N3179.48 (9)C7—N1—C8—N20.21 (17)
O2—N3—C3—C2179.07 (10)C10—N1—C8—N2174.96 (10)
O3—N3—C3—C20.50 (15)C7—N1—C8—C9179.98 (10)
O2—N3—C3—C41.17 (15)C10—N1—C8—C94.82 (15)
O3—N3—C3—C4179.26 (10)C8—N1—C10—C1188.12 (13)
C2—C3—C4—C50.36 (17)C7—N1—C10—C1196.47 (12)
N3—C3—C4—C5179.39 (9)C8—N1—C10—C1590.00 (12)
C3—C4—C5—C61.07 (16)C7—N1—C10—C1585.41 (13)
C4—C5—C6—C10.66 (16)C15—C10—C11—C121.87 (17)
C4—C5—C6—C7177.60 (10)N1—C10—C11—C12176.16 (10)
N2—C1—C6—C5178.50 (10)C10—C11—C12—C132.42 (17)
C2—C1—C6—C50.48 (16)C11—C12—C13—C140.49 (17)
N2—C1—C6—C70.22 (15)C12—C13—C14—C152.14 (17)
C2—C1—C6—C7178.77 (9)C11—C10—C15—C140.65 (16)
C8—N1—C7—O1179.25 (10)N1—C10—C15—C14178.70 (9)
C10—N1—C7—O15.51 (15)C11—C10—C15—C16178.64 (10)
C8—N1—C7—C61.94 (14)N1—C10—C15—C160.59 (16)
C10—N1—C7—C6173.30 (9)C13—C14—C15—C102.66 (16)
C5—C6—C7—O12.15 (17)C13—C14—C15—C16176.63 (10)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···O1i0.952.543.4530 (15)161
Symmetry code: (i) x+1, y, z+1/2.

Experimental details

Crystal data
Chemical formulaC16H13N3O3
Mr295.29
Crystal system, space groupMonoclinic, C2/c
Temperature (K)100
a, b, c (Å)14.4614 (5), 16.5383 (4), 12.9968 (4)
β (°) 119.072 (4)
V3)2716.78 (14)
Z8
Radiation typeCu Kα
µ (mm1)0.85
Crystal size (mm)0.25 × 0.25 × 0.25
Data collection
DiffractometerAgilent SuperNova Dual
diffractometer with an Atlas detector
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2011)
Tmin, Tmax0.967, 0.998
No. of measured, independent and
observed [I > 2σ(I)] reflections
5450, 2783, 2570
Rint0.013
(sin θ/λ)max1)0.631
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.099, 1.02
No. of reflections2783
No. of parameters201
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.24, 0.24

Computer programs: CrysAlis PRO (Agilent, 2011), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···O1i0.952.543.4530 (15)161
Symmetry code: (i) x+1, y, z+1/2.
 

Footnotes

Additional correspondence author, e-mail: adelazaba@yahoo.com.

Acknowledgements

This work was supported by the Research Center of Pharmacy, King Saud University, Riyadh, Saudi Arabia. The authors also thank the Ministry of Higher Education (Malaysia) for funding structural studies through the High-Impact Research scheme (grant No. UM·C/HIR/MOHE/SC/12).

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