Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807047393/hb2537sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807047393/hb2537Isup2.hkl |
CCDC reference: 667337
Key indicators
- Single-crystal X-ray study
- T = 296 K
- Mean (C-C) = 0.003 Å
- R factor = 0.049
- wR factor = 0.149
- Data-to-parameter ratio = 12.8
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT154_ALERT_1_C The su's on the Cell Angles are Equal (x 10000) 200 Deg. PLAT391_ALERT_3_C Deviating Methyl C17 H-C-H Bond Angle ...... 100.00 Deg.
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 2 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 0 ALERT type 2 Indicator that the structure model may be wrong or deficient 1 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
For related literature, see: Alagarsamy et al. (2003, 2004); El-Meligie et al. (2001).
A mixture of 2–methyl benzo(1,3) oxazin–4–one (0.01 mole; 1.61 g) and hydrazine hydrate (0.03 mole; 1.5 g) in ethanol was refluxed for two hours, then p-dimethyl amino benzaldehyde (2.24 g) was added. Then the solution was poured into ice cold water. The separated solid was filtered and recrystallized from ethanol and dried in an oven. Yield 73.1%; melting point 412–414 K. Yellow needles of (I) were recrystallized from ethyl acetate solution.
All the H atoms were positioned geometrically and their positions and Uiso values were freely refined.
Quinazolin related compounds exhibit multiple medicinal activities, such as analgesic (Alagarsamy et al., 2004), anti-inflammatory (Alagarsamy et al., 2003), and anticonvulsant (El-Meligie et al., 2001) properties. As part of our studies of these systems, we now present the synthesis and structure of the title compound, (I), (Fig. 1).
In the quinazolin ring, the single bond C—N distances [C8—N2 = 1.385 (2) Å; C7—N2 = 1.398 (2) Å and C3—N1 = 1.387 (2) Å] are almost equal and longer than C14—N4 [1.364 (2) Å]. The non-ring C—N bond distances such as C17—N4 and C18—N4 are significantly, longer than the above C—N distances. These differences are attributed to the different attached groups. As expected, the bridging bond C10—C11 [1.447 (2) Å] is much longer than the C—C distances of the rings in the molecule. The torsion angles N3—N2—C8—C9 and O1—C7—N2—N3 are -7.9 (2)° and 8.3 (2)° respectively. This small angle of bond twist indicate that the bonded atoms are cis oriented. In the molecule, the quinazolin ring and the benzylidene group are twisted with each other and the corresponding torsion angle is -178.2 (2)° confirms that the bonds are trans oriented. This wide-angle twist indicates that the the groups are significantly rotated and the dihedral angle between the planes is 54.0 (4)°. A small value of the dihedral angle [2.10 (4)°] between the aromatic and quinazolin rings show they are almost coplanar. The quinazolin ring is statistically planar with a maximum deviation of 0.02 (1) Å [C8].
The molecular packing is stabilized by C—H···O hydrogen bonding interactions which result in centrosymmetric dimers (Table 1, Fig. 2).
For related literature, see: Alagarsamy et al. (2003, 2004); El-Meligie et al. (2001).
Data collection: APEX2 not SMART (Bruker, ????); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997), PLATON (Spek, 2003); software used to prepare material for publication: WinGX (Farrugia, 1999).
C18H18N4O | Z = 2 |
Mr = 306.36 | F(000) = 324 |
Triclinic, P1 | Dx = 1.301 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.5175 (10) Å | Cell parameters from 50 reflections |
b = 9.3631 (13) Å | θ = 1.7–28.0° |
c = 12.7886 (17) Å | µ = 0.08 mm−1 |
α = 98.198 (2)° | T = 296 K |
β = 103.259 (2)° | Block, yellow |
γ = 112.517 (2)° | 0.21 × 0.18 × 0.10 mm |
V = 782.33 (18) Å3 |
Bruker APEXII CCD diffractometer | Rint = 0.021 |
ω scans | θmax = 28.0°, θmin = 1.7° |
9011 measured reflections | h = −9→9 |
3582 independent reflections | k = −12→12 |
2863 reflections with I > 2σ(I) | l = −16→16 |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | All H-atom parameters refined |
R[F2 > 2σ(F2)] = 0.049 | w = 1/[σ2(Fo2) + (0.0824P)2 + 0.0881P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.150 | (Δ/σ)max < 0.001 |
S = 1.03 | Δρmax = 0.16 e Å−3 |
3582 reflections | Δρmin = −0.18 e Å−3 |
280 parameters |
C18H18N4O | γ = 112.517 (2)° |
Mr = 306.36 | V = 782.33 (18) Å3 |
Triclinic, P1 | Z = 2 |
a = 7.5175 (10) Å | Mo Kα radiation |
b = 9.3631 (13) Å | µ = 0.08 mm−1 |
c = 12.7886 (17) Å | T = 296 K |
α = 98.198 (2)° | 0.21 × 0.18 × 0.10 mm |
β = 103.259 (2)° |
Bruker APEXII CCD diffractometer | 2863 reflections with I > 2σ(I) |
9011 measured reflections | Rint = 0.021 |
3582 independent reflections |
R[F2 > 2σ(F2)] = 0.049 | 0 restraints |
wR(F2) = 0.150 | All H-atom parameters refined |
S = 1.03 | Δρmax = 0.16 e Å−3 |
3582 reflections | Δρmin = −0.18 e Å−3 |
280 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | −0.0239 (3) | 0.7144 (2) | 0.16094 (15) | 0.0761 (5) | |
C2 | 0.1029 (2) | 0.63717 (16) | 0.16193 (11) | 0.0590 (4) | |
C3 | 0.2288 (3) | 0.66170 (16) | 0.09561 (11) | 0.0628 (4) | |
C4 | 0.2239 (4) | 0.7645 (2) | 0.02596 (14) | 0.0830 (5) | |
C5 | 0.0992 (4) | 0.8384 (2) | 0.02555 (17) | 0.0969 (7) | |
C6 | −0.0240 (4) | 0.8146 (2) | 0.09299 (16) | 0.0937 (7) | |
C7 | 0.0971 (2) | 0.52499 (16) | 0.23043 (11) | 0.0574 (3) | |
C8 | 0.3481 (2) | 0.48483 (17) | 0.15228 (11) | 0.0584 (3) | |
C9 | 0.4731 (3) | 0.3951 (3) | 0.14777 (16) | 0.0759 (5) | |
C10 | 0.25148 (19) | 0.35813 (15) | 0.37531 (11) | 0.0494 (3) | |
C11 | 0.25379 (18) | 0.23922 (15) | 0.43582 (10) | 0.0468 (3) | |
C12 | 0.2940 (2) | 0.27515 (16) | 0.55046 (11) | 0.0513 (3) | |
C13 | 0.3045 (2) | 0.16600 (17) | 0.61039 (11) | 0.0536 (3) | |
C14 | 0.27102 (18) | 0.01191 (15) | 0.55708 (10) | 0.0482 (3) | |
C15 | 0.2322 (2) | −0.02347 (16) | 0.44130 (11) | 0.0539 (3) | |
C16 | 0.2239 (2) | 0.08687 (16) | 0.38322 (11) | 0.0532 (3) | |
C17 | 0.3175 (4) | −0.0651 (3) | 0.73240 (15) | 0.0841 (6) | |
C18 | 0.2354 (3) | −0.25892 (19) | 0.55635 (16) | 0.0678 (4) | |
N1 | 0.3542 (2) | 0.58551 (16) | 0.09249 (10) | 0.0669 (4) | |
N2 | 0.22998 (18) | 0.45569 (13) | 0.22242 (9) | 0.0528 (3) | |
N3 | 0.22249 (19) | 0.32720 (13) | 0.27105 (9) | 0.0566 (3) | |
N4 | 0.27461 (19) | −0.10011 (14) | 0.61397 (10) | 0.0593 (3) | |
O1 | −0.01214 (18) | 0.49096 (15) | 0.28877 (10) | 0.0773 (4) | |
H1 | −0.117 (3) | 0.691 (3) | 0.2099 (18) | 0.104 (7)* | |
H4 | 0.315 (3) | 0.783 (2) | −0.0153 (17) | 0.085 (6)* | |
H5 | 0.097 (4) | 0.905 (3) | −0.023 (2) | 0.119 (7)* | |
H6 | −0.120 (4) | 0.861 (3) | 0.0914 (19) | 0.110 (7)* | |
H9A | 0.385 (4) | 0.279 (3) | 0.1317 (19) | 0.114 (7)* | |
H9B | 0.575 (3) | 0.424 (2) | 0.2179 (19) | 0.097 (6)* | |
H9C | 0.532 (3) | 0.415 (2) | 0.0904 (17) | 0.089 (6)* | |
H10 | 0.279 (2) | 0.4627 (18) | 0.4204 (12) | 0.057 (4)* | |
H12 | 0.313 (2) | 0.378 (2) | 0.5871 (13) | 0.063 (4)* | |
H13 | 0.333 (2) | 0.1965 (19) | 0.6874 (15) | 0.072 (5)* | |
H15 | 0.211 (2) | −0.125 (2) | 0.4051 (13) | 0.068 (4)* | |
H16 | 0.196 (2) | 0.0572 (19) | 0.3046 (14) | 0.070 (4)* | |
H17A | 0.243 (4) | −0.015 (3) | 0.757 (2) | 0.135 (10)* | |
H17B | 0.455 (4) | 0.021 (3) | 0.766 (2) | 0.126 (8)* | |
H17C | 0.314 (4) | −0.156 (3) | 0.757 (2) | 0.118 (7)* | |
H18A | 0.097 (3) | −0.314 (2) | 0.4942 (16) | 0.088 (5)* | |
H18B | 0.236 (4) | −0.319 (3) | 0.6088 (19) | 0.116 (7)* | |
H18C | 0.336 (3) | −0.255 (2) | 0.5189 (16) | 0.093 (6)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0992 (12) | 0.0659 (9) | 0.0662 (9) | 0.0470 (9) | 0.0123 (9) | 0.0144 (7) |
C2 | 0.0747 (9) | 0.0475 (7) | 0.0453 (7) | 0.0256 (6) | 0.0048 (6) | 0.0090 (5) |
C3 | 0.0849 (10) | 0.0481 (7) | 0.0441 (7) | 0.0242 (7) | 0.0071 (6) | 0.0122 (5) |
C4 | 0.1266 (16) | 0.0663 (10) | 0.0574 (9) | 0.0415 (11) | 0.0240 (10) | 0.0282 (8) |
C5 | 0.158 (2) | 0.0683 (11) | 0.0683 (11) | 0.0602 (13) | 0.0138 (12) | 0.0297 (9) |
C6 | 0.1408 (19) | 0.0795 (12) | 0.0722 (11) | 0.0703 (13) | 0.0122 (12) | 0.0210 (9) |
C7 | 0.0660 (8) | 0.0531 (7) | 0.0513 (7) | 0.0270 (6) | 0.0121 (6) | 0.0145 (6) |
C8 | 0.0695 (8) | 0.0597 (8) | 0.0453 (7) | 0.0268 (7) | 0.0162 (6) | 0.0168 (6) |
C9 | 0.0916 (12) | 0.0981 (14) | 0.0661 (10) | 0.0562 (11) | 0.0376 (10) | 0.0384 (10) |
C10 | 0.0482 (7) | 0.0472 (6) | 0.0506 (7) | 0.0196 (5) | 0.0122 (5) | 0.0143 (5) |
C11 | 0.0436 (6) | 0.0477 (6) | 0.0490 (6) | 0.0191 (5) | 0.0128 (5) | 0.0156 (5) |
C12 | 0.0546 (7) | 0.0479 (7) | 0.0504 (7) | 0.0222 (6) | 0.0152 (5) | 0.0111 (5) |
C13 | 0.0584 (7) | 0.0575 (7) | 0.0439 (7) | 0.0243 (6) | 0.0145 (5) | 0.0143 (5) |
C14 | 0.0422 (6) | 0.0523 (7) | 0.0537 (7) | 0.0211 (5) | 0.0160 (5) | 0.0202 (5) |
C15 | 0.0621 (8) | 0.0482 (7) | 0.0547 (7) | 0.0262 (6) | 0.0193 (6) | 0.0139 (6) |
C16 | 0.0614 (8) | 0.0533 (7) | 0.0451 (7) | 0.0248 (6) | 0.0158 (6) | 0.0140 (5) |
C17 | 0.1134 (16) | 0.0731 (11) | 0.0595 (9) | 0.0356 (12) | 0.0155 (10) | 0.0306 (8) |
C18 | 0.0755 (10) | 0.0576 (8) | 0.0822 (11) | 0.0337 (8) | 0.0294 (9) | 0.0308 (8) |
N1 | 0.0867 (9) | 0.0676 (7) | 0.0515 (7) | 0.0335 (7) | 0.0240 (6) | 0.0259 (6) |
N2 | 0.0647 (7) | 0.0482 (6) | 0.0464 (6) | 0.0245 (5) | 0.0152 (5) | 0.0176 (4) |
N3 | 0.0719 (7) | 0.0502 (6) | 0.0534 (6) | 0.0290 (5) | 0.0197 (5) | 0.0218 (5) |
N4 | 0.0667 (7) | 0.0593 (7) | 0.0600 (7) | 0.0306 (6) | 0.0209 (5) | 0.0269 (5) |
O1 | 0.0864 (8) | 0.0928 (8) | 0.0825 (8) | 0.0533 (7) | 0.0408 (6) | 0.0441 (6) |
C1—C6 | 1.367 (3) | C10—H10 | 0.982 (15) |
C1—C2 | 1.399 (2) | C11—C12 | 1.3900 (18) |
C1—H1 | 1.03 (2) | C11—C16 | 1.3963 (18) |
C2—C3 | 1.387 (2) | C12—C13 | 1.3768 (18) |
C2—C7 | 1.4552 (19) | C12—H12 | 0.950 (16) |
C3—N1 | 1.387 (2) | C13—C14 | 1.4044 (19) |
C3—C4 | 1.406 (2) | C13—H13 | 0.934 (17) |
C4—C5 | 1.362 (3) | C14—N4 | 1.3641 (16) |
C4—H4 | 0.939 (19) | C14—C15 | 1.4054 (19) |
C5—C6 | 1.384 (3) | C15—C16 | 1.3673 (18) |
C5—H5 | 0.95 (2) | C15—H15 | 0.931 (16) |
C6—H6 | 0.97 (2) | C16—H16 | 0.955 (17) |
C7—O1 | 1.2171 (18) | C17—N4 | 1.435 (2) |
C7—N2 | 1.3976 (19) | C17—H17A | 0.94 (3) |
C8—N1 | 1.2899 (17) | C17—H17B | 0.98 (3) |
C8—N2 | 1.3848 (18) | C17—H17C | 0.94 (3) |
C8—C9 | 1.486 (2) | C18—N4 | 1.447 (2) |
C9—H9A | 1.00 (2) | C18—H18A | 1.03 (2) |
C9—H9B | 0.96 (2) | C18—H18B | 0.94 (2) |
C9—H9C | 0.95 (2) | C18—H18C | 0.98 (2) |
C10—N3 | 1.2718 (17) | N2—N3 | 1.4194 (14) |
C10—C11 | 1.4467 (17) | ||
C6—C1—C2 | 119.2 (2) | C13—C12—C11 | 121.83 (12) |
C6—C1—H1 | 122.1 (12) | C13—C12—H12 | 120.1 (9) |
C2—C1—H1 | 118.6 (12) | C11—C12—H12 | 118.0 (9) |
C3—C2—C1 | 120.97 (14) | C12—C13—C14 | 120.87 (12) |
C3—C2—C7 | 119.54 (13) | C12—C13—H13 | 118.4 (10) |
C1—C2—C7 | 119.46 (15) | C14—C13—H13 | 120.7 (10) |
N1—C3—C2 | 122.88 (12) | N4—C14—C13 | 122.11 (12) |
N1—C3—C4 | 118.69 (16) | N4—C14—C15 | 120.78 (12) |
C2—C3—C4 | 118.40 (16) | C13—C14—C15 | 117.12 (11) |
C5—C4—C3 | 120.0 (2) | C16—C15—C14 | 121.21 (12) |
C5—C4—H4 | 123.4 (12) | C16—C15—H15 | 120.8 (10) |
C3—C4—H4 | 116.5 (12) | C14—C15—H15 | 118.0 (10) |
C4—C5—C6 | 121.16 (17) | C15—C16—C11 | 121.76 (12) |
C4—C5—H5 | 118.5 (15) | C15—C16—H16 | 118.2 (10) |
C6—C5—H5 | 120.4 (15) | C11—C16—H16 | 120.1 (10) |
C1—C6—C5 | 120.2 (2) | N4—C17—H17A | 112.6 (17) |
C1—C6—H6 | 116.6 (14) | N4—C17—H17B | 107.8 (15) |
C5—C6—H6 | 123.0 (14) | H17A—C17—H17B | 100 (2) |
O1—C7—N2 | 121.87 (12) | N4—C17—H17C | 109.6 (15) |
O1—C7—C2 | 124.86 (14) | H17A—C17—H17C | 117 (2) |
N2—C7—C2 | 113.27 (13) | H17B—C17—H17C | 108 (2) |
N1—C8—N2 | 123.02 (13) | N4—C18—H18A | 111.7 (10) |
N1—C8—C9 | 119.66 (14) | N4—C18—H18B | 107.7 (14) |
N2—C8—C9 | 117.33 (13) | H18A—C18—H18B | 109.7 (18) |
C8—C9—H9A | 109.1 (14) | N4—C18—H18C | 111.0 (12) |
C8—C9—H9B | 111.3 (12) | H18A—C18—H18C | 105.4 (16) |
H9A—C9—H9B | 107.1 (18) | H18B—C18—H18C | 111.3 (18) |
C8—C9—H9C | 108.8 (12) | C8—N1—C3 | 117.79 (13) |
H9A—C9—H9C | 109.7 (18) | C8—N2—C7 | 123.41 (11) |
H9B—C9—H9C | 110.8 (18) | C8—N2—N3 | 115.22 (11) |
N3—C10—C11 | 120.72 (12) | C7—N2—N3 | 120.37 (11) |
N3—C10—H10 | 123.6 (8) | C10—N3—N2 | 115.05 (11) |
C11—C10—H10 | 115.6 (8) | C14—N4—C17 | 121.49 (13) |
C12—C11—C16 | 117.20 (11) | C14—N4—C18 | 120.79 (13) |
C12—C11—C10 | 120.75 (12) | C17—N4—C18 | 117.72 (14) |
C16—C11—C10 | 122.01 (11) | ||
C6—C1—C2—C3 | 0.4 (2) | C13—C14—C15—C16 | −1.1 (2) |
C6—C1—C2—C7 | −177.34 (15) | C14—C15—C16—C11 | 0.1 (2) |
C1—C2—C3—N1 | −178.80 (13) | C12—C11—C16—C15 | 0.5 (2) |
C7—C2—C3—N1 | −1.1 (2) | C10—C11—C16—C15 | 178.05 (12) |
C1—C2—C3—C4 | −0.9 (2) | N2—C8—N1—C3 | −3.0 (2) |
C7—C2—C3—C4 | 176.80 (13) | C9—C8—N1—C3 | 177.34 (15) |
N1—C3—C4—C5 | 178.65 (16) | C2—C3—N1—C8 | 1.7 (2) |
C2—C3—C4—C5 | 0.7 (3) | C4—C3—N1—C8 | −176.17 (14) |
C3—C4—C5—C6 | 0.1 (3) | N1—C8—N2—C7 | 3.9 (2) |
C2—C1—C6—C5 | 0.4 (3) | C9—C8—N2—C7 | −176.45 (15) |
C4—C5—C6—C1 | −0.7 (3) | N1—C8—N2—N3 | 172.45 (12) |
C3—C2—C7—O1 | −177.59 (14) | C9—C8—N2—N3 | −7.92 (19) |
C1—C2—C7—O1 | 0.1 (2) | O1—C7—N2—C8 | 176.29 (13) |
C3—C2—C7—N2 | 1.63 (18) | C2—C7—N2—C8 | −2.96 (19) |
C1—C2—C7—N2 | 179.36 (13) | O1—C7—N2—N3 | 8.3 (2) |
N3—C10—C11—C12 | 177.24 (12) | C2—C7—N2—N3 | −170.92 (11) |
N3—C10—C11—C16 | −0.3 (2) | C11—C10—N3—N2 | −178.16 (10) |
C16—C11—C12—C13 | 0.07 (19) | C8—N2—N3—C10 | 132.15 (13) |
C10—C11—C12—C13 | −177.54 (11) | C7—N2—N3—C10 | −58.94 (16) |
C11—C12—C13—C14 | −1.2 (2) | C13—C14—N4—C17 | −1.4 (2) |
C12—C13—C14—N4 | −178.04 (11) | C15—C14—N4—C17 | 178.90 (16) |
C12—C13—C14—C15 | 1.67 (19) | C13—C14—N4—C18 | 178.72 (13) |
N4—C14—C15—C16 | 178.58 (12) | C15—C14—N4—C18 | −1.0 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
C18—H18B···O1i | 0.94 (2) | 2.58 (3) | 3.379 (2) | 143.0 (19) |
Symmetry code: (i) −x, −y, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C18H18N4O |
Mr | 306.36 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 296 |
a, b, c (Å) | 7.5175 (10), 9.3631 (13), 12.7886 (17) |
α, β, γ (°) | 98.198 (2), 103.259 (2), 112.517 (2) |
V (Å3) | 782.33 (18) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.21 × 0.18 × 0.10 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 9011, 3582, 2863 |
Rint | 0.021 |
(sin θ/λ)max (Å−1) | 0.660 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.049, 0.150, 1.03 |
No. of reflections | 3582 |
No. of parameters | 280 |
H-atom treatment | All H-atom parameters refined |
Δρmax, Δρmin (e Å−3) | 0.16, −0.18 |
Computer programs: APEX2 not SMART (Bruker, ????), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEP-3 (Farrugia, 1997), PLATON (Spek, 2003), WinGX (Farrugia, 1999).
D—H···A | D—H | H···A | D···A | D—H···A |
C18—H18B···O1i | 0.94 (2) | 2.58 (3) | 3.379 (2) | 143.0 (19) |
Symmetry code: (i) −x, −y, −z+1. |
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Quinazolin related compounds exhibit multiple medicinal activities, such as analgesic (Alagarsamy et al., 2004), anti-inflammatory (Alagarsamy et al., 2003), and anticonvulsant (El-Meligie et al., 2001) properties. As part of our studies of these systems, we now present the synthesis and structure of the title compound, (I), (Fig. 1).
In the quinazolin ring, the single bond C—N distances [C8—N2 = 1.385 (2) Å; C7—N2 = 1.398 (2) Å and C3—N1 = 1.387 (2) Å] are almost equal and longer than C14—N4 [1.364 (2) Å]. The non-ring C—N bond distances such as C17—N4 and C18—N4 are significantly, longer than the above C—N distances. These differences are attributed to the different attached groups. As expected, the bridging bond C10—C11 [1.447 (2) Å] is much longer than the C—C distances of the rings in the molecule. The torsion angles N3—N2—C8—C9 and O1—C7—N2—N3 are -7.9 (2)° and 8.3 (2)° respectively. This small angle of bond twist indicate that the bonded atoms are cis oriented. In the molecule, the quinazolin ring and the benzylidene group are twisted with each other and the corresponding torsion angle is -178.2 (2)° confirms that the bonds are trans oriented. This wide-angle twist indicates that the the groups are significantly rotated and the dihedral angle between the planes is 54.0 (4)°. A small value of the dihedral angle [2.10 (4)°] between the aromatic and quinazolin rings show they are almost coplanar. The quinazolin ring is statistically planar with a maximum deviation of 0.02 (1) Å [C8].
The molecular packing is stabilized by C—H···O hydrogen bonding interactions which result in centrosymmetric dimers (Table 1, Fig. 2).