supplementary materials


lh5622 scheme

Acta Cryst. (2013). E69, o1111    [ doi:10.1107/S1600536813016127 ]

Methyl 3-[(6-nitro-4-oxo-3-phenyl-3,4-dihydroquinazolin-2-yl)sulfanyl]propanoate

I. A. Al-Suwaidan, A. A.-M. Abdel-Aziz, A. S. El-Azab, C. S. Chidan Kumar and H.-K. Fun

Abstract top

In the title compound, C18H15N3O5S, the approximately planar quinazoline ring system [maximum deviation = 0.097 (3) Å] forms a dihedral angle of 76.53 (19)° with the phenyl ring. The terminal -C(=O)-O-C group is disordered over two sets of sites with a site-occupancy ratio of 0.811 (17):0.189 (17). In the crystal, molecules are linked via weak C-H...O hydrogen bonds into sheets parallel to the ac plane.

Comment top

Quinazolines are considered to be important chemical synthons of physiological significance and pharmaceutical utility. They possess a variety of biological effects including antimicrobial (El-Azab et al., 2007), anti-inflammatory (Alafeefy et al., 2008), anticonvulsant, (El-Azab et al., 2011; El-Azab & ElTahir 2012a,b) and anticancer activities (El-Azab et al., 2010; El-Azab & ElTahir 2012b; Al-Suwaidan et al., 2013). These observations have been the guidelines for the development of new quinazolines which possess varied biological activities. Prompted by the potential biological activities of quinazolines, the title compound was synthesized and its crystal structure is reported herein.

The molecular structure of the title compound is shown in Fig. 1. The quinazoline ring (C1–C8/N1–N2; maximum deviation = 0.097 (3) Å at atom N2) makes a dihedral angle of 76.53 (19)° with the attached phenyl ring (C9–C14). The terminal C17(O1)—O5—C18 group is disordered over two positions with a site-occupancy ratio of 0.811 (17): 0.189 (17). In the crystal structure (Fig. 2), the molecules are linked via weak intermolecular C6—H6A···O2i and C10—H10A···O2ii hydrogen bonds (see Table 1 for symmetry codes) into sheets parallel to the ac plane.

Related literature top

For background to quinazoline chemistry, see: El-Azab (2007); El-Azab et al. (2010, 2011); Alafeefy et al. (2008); Al-Suwaidan et al. (2013); El-Azab & ElTahir (2012a,b). For standard bond-length data, see: Allen et al. (1987).

Experimental top

A mixture of 3-phenyl-2-mercapto-6-nitro-quinazolin-4(3H)-one (2.99 g, 0.01 mol) and Et3N (2 ml) in CH2Cl2 (30 ml) was stirred in an ice bath and acryloyl chloride (3.3 ml, 0.04 mol) was added dropwise over a period of 15 min. Stirring was performed in an ice bath for 1 h and then at room temperature overnight. Solvent was then removed under reduced pressure and the obtained residue was dissolved in CH2Cl2 and washed with 10% NaOH solution and water. The resultant was separated and dried over MgSO4 then evaporated in vacuo. The obtained residue was chromatographed on silica gel using 10% EtOAc/hexane as eluant and recrystallized from hexane/CH2Cl2 (92%) (m.p:. 480 K) to yield X-ray quality crystals.

Refinement top

The hydrogen atoms were positioned geometrically [C–H = 0.93, 0.96 and 0.97 Å] and were refined using a riding model, with Uiso(H) = 1.2 Ueq(C) or 1.5Ueq(methyl C). A rotating-group model was used for the methyl groups. The terminal C17(O1)—O5—C18 group is disordered over two positions with a site-occupancy ratio of 0.811 (17): 0.189 (17). The SHELXL (Sheldrick, 2008) EXYZ (same x, y and z parameters) and EADP (same Uij parameters) restraints were used for atoms pairs C17/C17A.The same distance restraints were applied to (C17/O1 & C17A/O1A), (C17/O5 & C17A/O5A) and (C18/O5 & C18A/O5A). The SIMU (similar Uij parameters) restraint was applied to C18/C18A.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with 30% probability displacement ellipsoids. The minor component of disorder is shown as open bonds
[Figure 2] Fig. 2. The crystal packing of the title compound. The minor component of disorder and H atoms not involved in the intermolecular interactions (dashed lines) have been omitted for clarity.
Methyl 3-[(6-nitro-4-oxo-3-phenyl-3,4-dihydroquinazolin-2-yl)sulfanyl]propanoate top
Crystal data top
C18H15N3O5SF(000) = 800
Mr = 385.39Dx = 1.399 Mg m3
Monoclinic, P21/nMelting point: 480 K
Hall symbol: -P 2ynCu Kα radiation, λ = 1.54178 Å
a = 4.9146 (3) ÅCell parameters from 1209 reflections
b = 26.5065 (18) Åθ = 3.3–67.5°
c = 14.0900 (9) ŵ = 1.89 mm1
β = 94.645 (4)°T = 296 K
V = 1829.5 (2) Å3Block, colourless
Z = 40.32 × 0.26 × 0.13 mm
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3382 independent reflections
Radiation source: fine-focus sealed tube1861 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.059
φ and ω scansθmax = 69.8°, θmin = 3.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 54
Tmin = 0.583, Tmax = 0.791k = 3131
12669 measured reflectionsl = 1717
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.064H-atom parameters constrained
wR(F2) = 0.191 w = 1/[σ2(Fo2) + (0.0825P)2 + 0.1932P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max < 0.001
3382 reflectionsΔρmax = 0.24 e Å3
273 parametersΔρmin = 0.16 e Å3
9 restraintsExtinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0030 (5)
Crystal data top
C18H15N3O5SV = 1829.5 (2) Å3
Mr = 385.39Z = 4
Monoclinic, P21/nCu Kα radiation
a = 4.9146 (3) ŵ = 1.89 mm1
b = 26.5065 (18) ÅT = 296 K
c = 14.0900 (9) Å0.32 × 0.26 × 0.13 mm
β = 94.645 (4)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3382 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
1861 reflections with I > 2σ(I)
Tmin = 0.583, Tmax = 0.791Rint = 0.059
12669 measured reflectionsθmax = 69.8°
Refinement top
R[F2 > 2σ(F2)] = 0.064H-atom parameters constrained
wR(F2) = 0.191Δρmax = 0.24 e Å3
S = 1.03Δρmin = 0.16 e Å3
3382 reflectionsAbsolute structure: ?
273 parametersAbsolute structure parameter: ?
9 restraintsRogers parameter: ?
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)
S10.3830 (2)0.12146 (4)0.63782 (7)0.0880 (4)
O20.8688 (6)0.19581 (12)0.38141 (18)0.0982 (9)
O31.5168 (8)0.33688 (17)0.4490 (3)0.1442 (16)
O41.6007 (9)0.36422 (17)0.5910 (3)0.1520 (16)
N10.7309 (6)0.19860 (13)0.6615 (2)0.0790 (9)
N20.6827 (6)0.16072 (12)0.50857 (19)0.0741 (8)
N31.4799 (8)0.33704 (17)0.5326 (4)0.1094 (13)
C10.6245 (7)0.16499 (15)0.6034 (2)0.0738 (9)
C20.8395 (7)0.19721 (16)0.4673 (3)0.0786 (10)
C30.9676 (7)0.23374 (15)0.5321 (2)0.0760 (10)
C41.1534 (8)0.26847 (16)0.5010 (3)0.0849 (11)
H4A1.19120.26940.43740.102*
C51.2796 (8)0.30119 (17)0.5656 (3)0.0884 (11)
C61.2314 (9)0.30066 (18)0.6598 (3)0.0984 (13)
H6A1.32290.32290.70230.118*
C71.0479 (9)0.26718 (17)0.6906 (3)0.0927 (12)
H7A1.01170.26710.75440.111*
C80.9117 (7)0.23265 (15)0.6269 (3)0.0787 (10)
C90.5906 (7)0.11756 (17)0.4514 (2)0.0783 (10)
C100.3811 (8)0.1233 (2)0.3819 (3)0.0991 (14)
H10A0.29850.15450.37060.119*
C110.2955 (11)0.0814 (3)0.3288 (4)0.1243 (19)
H11A0.15160.08440.28200.149*
C120.4181 (12)0.0363 (3)0.3440 (4)0.1245 (19)
H12A0.35670.00840.30850.149*
C130.6334 (11)0.0314 (2)0.4119 (4)0.1198 (17)
H13A0.72080.00040.42120.144*
C140.7186 (9)0.07209 (18)0.4656 (3)0.1008 (14)
H14A0.86360.06890.51180.121*
C150.3526 (9)0.14022 (17)0.7595 (2)0.0889 (12)
H15A0.45550.17100.77240.107*
H15B0.16250.14730.76820.107*
C160.4560 (8)0.09993 (17)0.8302 (3)0.0871 (11)
H16A0.64270.09160.81880.105*
H16B0.45720.11360.89410.105*
C170.2895 (9)0.05291 (19)0.8246 (3)0.0925 (13)0.811 (17)
O10.085 (3)0.0464 (8)0.7732 (11)0.107 (4)0.811 (17)
O50.4116 (19)0.0176 (3)0.8814 (6)0.118 (3)0.811 (17)
C180.264 (3)0.0316 (3)0.8826 (7)0.157 (4)0.811 (17)
H18A0.36900.05510.92230.235*0.811 (17)
H18B0.23810.04470.81900.235*0.811 (17)
H18C0.08920.02660.90720.235*0.811 (17)
C17A0.2895 (9)0.05291 (19)0.8246 (3)0.0925 (13)0.189 (17)
O1A0.120 (14)0.048 (4)0.759 (5)0.115 (18)0.189 (17)
O5A0.293 (6)0.0223 (10)0.9005 (15)0.089 (7)0.189 (17)
C18A0.134 (10)0.0214 (14)0.934 (3)0.156 (7)0.189 (17)
H18D0.21310.03240.99520.234*0.189 (17)
H18E0.13760.04860.88930.234*0.189 (17)
H18F0.05170.01120.93960.234*0.189 (17)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0921 (7)0.0934 (8)0.0790 (6)0.0061 (5)0.0095 (4)0.0080 (6)
O20.119 (2)0.109 (3)0.0674 (15)0.0031 (17)0.0072 (13)0.0014 (16)
O30.148 (3)0.169 (4)0.119 (3)0.039 (3)0.023 (2)0.034 (3)
O40.163 (4)0.138 (4)0.153 (3)0.056 (3)0.003 (3)0.003 (3)
N10.092 (2)0.077 (2)0.0678 (17)0.0000 (16)0.0039 (14)0.0049 (17)
N20.0814 (19)0.078 (2)0.0622 (16)0.0074 (15)0.0006 (13)0.0056 (16)
N30.103 (3)0.103 (3)0.120 (3)0.006 (2)0.004 (2)0.024 (3)
C10.080 (2)0.073 (3)0.068 (2)0.0073 (17)0.0035 (15)0.001 (2)
C20.086 (2)0.083 (3)0.066 (2)0.012 (2)0.0007 (17)0.001 (2)
C30.088 (2)0.071 (3)0.068 (2)0.0111 (19)0.0005 (16)0.0045 (19)
C40.090 (3)0.085 (3)0.079 (2)0.010 (2)0.0033 (19)0.013 (2)
C50.092 (3)0.080 (3)0.092 (3)0.002 (2)0.002 (2)0.012 (2)
C60.117 (3)0.089 (3)0.088 (3)0.016 (3)0.006 (2)0.001 (3)
C70.116 (3)0.091 (3)0.071 (2)0.007 (2)0.003 (2)0.004 (2)
C80.090 (2)0.072 (3)0.073 (2)0.0019 (19)0.0002 (17)0.001 (2)
C90.082 (2)0.086 (3)0.067 (2)0.004 (2)0.0031 (16)0.007 (2)
C100.095 (3)0.115 (4)0.085 (3)0.009 (2)0.010 (2)0.016 (3)
C110.111 (4)0.161 (6)0.098 (3)0.008 (4)0.015 (3)0.030 (4)
C120.129 (4)0.137 (6)0.108 (4)0.031 (4)0.012 (3)0.049 (4)
C130.136 (4)0.095 (4)0.130 (4)0.000 (3)0.016 (3)0.038 (3)
C140.104 (3)0.095 (4)0.100 (3)0.006 (3)0.008 (2)0.026 (3)
C150.100 (3)0.093 (3)0.076 (2)0.003 (2)0.0171 (19)0.008 (2)
C160.082 (2)0.094 (3)0.085 (2)0.001 (2)0.0058 (19)0.007 (2)
C170.092 (3)0.102 (4)0.083 (3)0.011 (2)0.005 (2)0.009 (3)
O10.089 (5)0.119 (7)0.110 (6)0.015 (5)0.006 (6)0.006 (5)
O50.132 (6)0.111 (4)0.109 (4)0.017 (4)0.014 (4)0.020 (3)
C180.229 (11)0.110 (6)0.130 (7)0.069 (7)0.011 (6)0.006 (5)
C17A0.092 (3)0.102 (4)0.083 (3)0.011 (2)0.005 (2)0.009 (3)
O1A0.10 (3)0.14 (3)0.10 (2)0.05 (2)0.028 (16)0.02 (2)
O5A0.083 (15)0.101 (15)0.082 (12)0.005 (11)0.005 (9)0.027 (10)
C18A0.226 (15)0.103 (11)0.137 (12)0.061 (11)0.004 (11)0.006 (11)
Geometric parameters (Å, º) top
S1—C11.752 (4)C10—H10A0.9300
S1—C151.803 (4)C11—C121.348 (7)
O2—C21.231 (4)C11—H11A0.9300
O3—N31.207 (5)C12—C131.374 (7)
O4—N31.212 (5)C12—H12A0.9300
N1—C11.291 (4)C13—C141.364 (6)
N1—C81.382 (5)C13—H13A0.9300
N2—C21.393 (5)C14—H14A0.9300
N2—C11.394 (4)C15—C161.519 (5)
N2—C91.451 (5)C15—H15A0.9700
N3—C51.470 (6)C15—H15B0.9700
C2—C31.440 (5)C16—C171.489 (6)
C3—C81.386 (5)C16—H16A0.9700
C3—C41.393 (5)C16—H16B0.9700
C4—C51.369 (5)C17—O11.204 (7)
C4—H4A0.9300C17—O51.342 (6)
C5—C61.367 (6)O5—C181.494 (8)
C6—C71.361 (6)C18—H18A0.9600
C6—H6A0.9300C18—H18B0.9600
C7—C81.412 (5)C18—H18C0.9600
C7—H7A0.9300O5A—C18A1.496 (9)
C9—C141.367 (6)C18A—H18D0.9600
C9—C101.371 (5)C18A—H18E0.9600
C10—C111.385 (7)C18A—H18F0.9600
C1—S1—C15101.0 (2)C12—C11—H11A119.6
C1—N1—C8117.8 (3)C10—C11—H11A119.6
C2—N2—C1120.5 (3)C11—C12—C13120.3 (5)
C2—N2—C9118.3 (3)C11—C12—H12A119.9
C1—N2—C9121.2 (3)C13—C12—H12A119.9
O3—N3—O4124.1 (5)C14—C13—C12119.7 (5)
O3—N3—C5117.6 (5)C14—C13—H13A120.1
O4—N3—C5118.3 (5)C12—C13—H13A120.1
N1—C1—N2124.0 (4)C13—C14—C9120.0 (4)
N1—C1—S1121.9 (3)C13—C14—H14A120.0
N2—C1—S1114.1 (3)C9—C14—H14A120.0
O2—C2—N2120.1 (4)C16—C15—S1112.3 (3)
O2—C2—C3124.3 (4)C16—C15—H15A109.1
N2—C2—C3115.5 (3)S1—C15—H15A109.1
C8—C3—C4120.3 (4)C16—C15—H15B109.1
C8—C3—C2119.1 (4)S1—C15—H15B109.1
C4—C3—C2120.6 (3)H15A—C15—H15B107.9
C5—C4—C3118.9 (4)C17—C16—C15113.6 (4)
C5—C4—H4A120.6C17—C16—H16A108.8
C3—C4—H4A120.6C15—C16—H16A108.8
C6—C5—C4122.3 (4)C17—C16—H16B108.8
C6—C5—N3119.1 (4)C15—C16—H16B108.8
C4—C5—N3118.6 (4)H16A—C16—H16B107.7
C7—C6—C5119.2 (4)O1—C17—O5124.8 (11)
C7—C6—H6A120.4O1—C17—C16125.5 (11)
C5—C6—H6A120.4O5—C17—C16109.6 (5)
C6—C7—C8120.8 (4)C17—O5—C18114.9 (7)
C6—C7—H7A119.6O5—C18—H18A109.5
C8—C7—H7A119.6O5—C18—H18B109.5
N1—C8—C3122.4 (3)H18A—C18—H18B109.5
N1—C8—C7119.0 (3)O5—C18—H18C109.5
C3—C8—C7118.6 (4)H18A—C18—H18C109.5
C14—C9—C10120.8 (4)H18B—C18—H18C109.5
C14—C9—N2119.7 (3)O5A—C18A—H18D109.5
C10—C9—N2119.5 (4)O5A—C18A—H18E109.5
C9—C10—C11118.4 (5)H18D—C18A—H18E109.5
C9—C10—H10A120.8O5A—C18A—H18F109.5
C11—C10—H10A120.8H18D—C18A—H18F109.5
C12—C11—C10120.8 (5)H18E—C18A—H18F109.5
C8—N1—C1—N20.6 (5)C1—N1—C8—C34.1 (6)
C8—N1—C1—S1177.5 (3)C1—N1—C8—C7174.9 (3)
C2—N2—C1—N17.6 (5)C4—C3—C8—N1179.4 (3)
C9—N2—C1—N1170.2 (3)C2—C3—C8—N11.9 (6)
C2—N2—C1—S1170.6 (3)C4—C3—C8—C70.3 (6)
C9—N2—C1—S111.6 (4)C2—C3—C8—C7177.2 (3)
C15—S1—C1—N10.6 (4)C6—C7—C8—N1178.7 (4)
C15—S1—C1—N2177.6 (3)C6—C7—C8—C30.4 (6)
C1—N2—C2—O2173.2 (3)C2—N2—C9—C14103.2 (4)
C9—N2—C2—O29.0 (5)C1—N2—C9—C1474.6 (5)
C1—N2—C2—C39.3 (5)C2—N2—C9—C1074.9 (5)
C9—N2—C2—C3168.6 (3)C1—N2—C9—C10107.2 (4)
O2—C2—C3—C8177.8 (4)C14—C9—C10—C112.4 (7)
N2—C2—C3—C84.8 (5)N2—C9—C10—C11179.5 (4)
O2—C2—C3—C44.7 (6)C9—C10—C11—C121.0 (8)
N2—C2—C3—C4172.7 (3)C10—C11—C12—C131.0 (9)
C8—C3—C4—C50.2 (6)C11—C12—C13—C141.7 (8)
C2—C3—C4—C5177.3 (3)C12—C13—C14—C90.3 (8)
C3—C4—C5—C60.6 (6)C10—C9—C14—C131.7 (7)
C3—C4—C5—N3178.7 (3)N2—C9—C14—C13179.8 (4)
O3—N3—C5—C6179.5 (5)C1—S1—C15—C16114.3 (3)
O4—N3—C5—C61.7 (7)S1—C15—C16—C1765.9 (4)
O3—N3—C5—C42.3 (6)C15—C16—C17—O13.1 (14)
O4—N3—C5—C4176.5 (4)C15—C16—C17—O5173.2 (6)
C4—C5—C6—C71.3 (7)O1—C17—O5—C183.9 (15)
N3—C5—C6—C7179.4 (4)C16—C17—O5—C18179.8 (6)
C5—C6—C7—C81.2 (7)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6A···O2i0.932.563.142 (5)121
C10—H10A···O2ii0.932.393.167 (5)140
Symmetry codes: (i) x+1/2, y+1/2, z+1/2; (ii) x1, y, z.

Experimental details

Crystal data
Chemical formulaC18H15N3O5S
Mr385.39
Crystal system, space groupMonoclinic, P21/n
Temperature (K)296
a, b, c (Å)4.9146 (3), 26.5065 (18), 14.0900 (9)
β (°) 94.645 (4)
V3)1829.5 (2)
Z4
Radiation typeCu Kα
µ (mm1)1.89
Crystal size (mm)0.32 × 0.26 × 0.13
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.583, 0.791
No. of measured, independent and
observed [I > 2σ(I)] reflections
12669, 3382, 1861
Rint0.059
(sin θ/λ)max1)0.609
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.064, 0.191, 1.03
No. of reflections3382
No. of parameters273
No. of restraints9
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.24, 0.16

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6A···O2i0.932.563.142 (5)120.7
C10—H10A···O2ii0.93002.39003.167 (5)140.00
Symmetry codes: (i) x+1/2, y+1/2, z+1/2; (ii) x1, y, z.
Acknowledgements top

The authors thank the Deanship of Scientific Research and the Research Center of the College of Pharmacy, King Saud University. CSC thanks Universiti Sains Malaysia for a postdoctoral research fellowship.

references
References top

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