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ISSN: 2056-9890

7H-[1,2]Benzo­thia­zolo[3,2-b]quinazoline 5,5-dioxide

aDepartment of Physics, RKM Vivekananda College (Autonomous), Chennai 600 004, India
*Correspondence e-mail: ksethusankar@yahoo.co.in

(Received 10 September 2012; accepted 28 September 2012; online 6 October 2012)

In the title compound, C14H10N2O2S, the benzothia­zole and quinazoline ring systems are essentially planar with maximum deviations of 0.0127 (16) and 0.1588 (15) Å, respectively, and make a dihedral angleof 3.02 (5)°, which shows that the entire mol­ecule is almost planar. The O atoms deviate from the benzothia­zole ring system by 1.2231 (14) and −1.1989 (15) Å. The crystal packing features non–classical C—H⋯O hydrogen bonds and is further consolidated by ππ inter­actions [centroid–centroid distances = 3.7568 (8) and 3.8848 (9) Å].

Related literature

For the uses and biological importance of benzothia­zole and quinazoline derivatives, see: Schwartz et al. (1992[Schwartz, A., Madan, P. B., Mohacsi, E., O-Brien, J. P., Todaro, L. J. & Coffen, D. L. (1992). J. Org. Chem. 57, 851-856.]); Wolfe et al. (1990[Wolfe, J. F., Rathman, T. L., Sleevi, M. C., Cambell, J. S. A. & Greenwood, T. D. (1990). J. Med. Chem. 33, 161-166.]); Tereshima et al. (1995[Tereshima, K., Shimamura, H., Kawase, A., Tanaka, Y., Tanimura, T., Ishizuka, Y. & Sato, M. (1995). Chem. Pharm. Bull. 45, 2021-2023.]). For related structures, see: Khan et al. (2012[Khan, M. H., Khan, I. U., Mughal, S. Y. & Akkurt, M. (2012). Acta Cryst. E68, o507.]); Grundt et al. (2010[Grundt, P., Douglas, K. A., Krivogorsky, B. & Nemykin, V. N. (2010). Acta Cryst. E66, o1474-o1475.]).

[Scheme 1]

Experimental

Crystal data
  • C14H10N2O2S

  • Mr = 270.31

  • Orthorhombic, P b c a

  • a = 7.9389 (2) Å

  • b = 13.1460 (4) Å

  • c = 22.7952 (7) Å

  • V = 2379.02 (12) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.27 mm−1

  • T = 295 K

  • 0.30 × 0.25 × 0.20 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.922, Tmax = 0.947

  • 21710 measured reflections

  • 2328 independent reflections

  • 1981 reflections with I > 2σ(I)

  • Rint = 0.028

Refinement
  • R[F2 > 2σ(F2)] = 0.034

  • wR(F2) = 0.122

  • S = 1.06

  • 2328 reflections

  • 172 parameters

  • H-atom parameters constrained

  • Δρmax = 0.25 e Å−3

  • Δρmin = −0.33 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C2—H2⋯O1i 0.93 2.43 3.275 (2) 150
Symmetry code: (i) [x-{\script{1\over 2}}, y, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2, 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: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Saccharin belongs to a class of cyclic sulfonamides and this is used as an artificial sweetener for a longtime. The benzothiazole and quinazoline derivatives form an important classes of fused heterocyclic compounds with a wide range of biological activities such as antimicrobial (Schwartz et al., 1992), anticancer (Wolfe et al., 1990), antiinflammatory (Tereshima et al., 1995). As a part of our studies in this area, the molecular and crystal structures of the title compound have been determined and the results are presented here.

The title compound comprises a benzothiazole ring fused with quinazoline ring. X–ray analysis confirms the molecular structure and atom connectivity as illustrated in Fig. 1. The benzothiazole ring system is essentially planar with a maximum deviation of -0.0127 (16)Å for the C7 atom. The quinazoline ring system is also essentially planar with the maximum deviation of -0.1588 (15)Å for the N1 atom. The dihedral angle between the benzothiazole and quinazoline ring systems are almost coplanar with a dihedral angle of 3.02 (5)° between them.

In the benzothiazole ring system, the oxygen atoms (O1 and O2) attached to the sulfur atom are significantly deviate from the least square plane of the ring system by 1.2231 (14)Å and -1.1989 (15)Å, respectively. The thiazole ring (C1/C6/C7/N1/S1) forms a dihedral angle of 0.34 (8)° and 3.15 (6)° with the phenyl ring (C1–C6) and the quinazoline ring system, respectively. The phenyl ring (C9–C14) forms the dihedral angles of 5.01 (8)° and 5.41 (7)° with the pyrimidine ring (N1/N2/C7–C10) and the phenyl ring (C1–C6), respectively. The title compound exibits the structural similarities with already reported structures (Khan et al., 2012; Grundt et al., 2010).

The crystal packing is stabilized by C2—H2···O1i intermolecular non–classical hydrogen bond (Table 1). The crystal packing is further stabilized by π···π interactions, with Cg1···Cg4ii and Cg3···Cg4ii distances being 3.7568 (8)Å and 3.8846 (9)Å, respectively, where Cg1 is the centre of gravity of (C1/C6/C7/N1/S1) ring; Cg3 is the centre of gravity of (C1–C6) ring; Cg4 is the centre of gravity of (C9–C14) ring. The symmetry codes: (i) -1/2+x, y, 1/2-z; (ii) -x, 1-y, 1-z. The packing view of the title compound is shown in Fig. 2.

Related literature top

For the uses and biological importance of benzothiazole and quinazoline derivatives, see: Schwartz et al. (1992); Wolfe et al. (1990); Tereshima et al. (1995). For related structures, see: Khan et al. (2012); Grundt et al. (2010).

Experimental top

A solution of Saccharin (0.91 g, 5 mmol) and o–amino benzyl alcohol (0.61 g, 5 mmol) in DMF (10 ml) was irradiated with microwaves in a 800 W domestic microwave oven for 2 minutes. The reaction solution was cooled and poured over crushed ice (200 g). The precipitated product was filtered and desiccated over anhydrous CaCl2. The resulting filetered product was subjected to crystallization by slow evaporation of the solvent resulting in single crystals suitable for XRD studies.

Refinement top

The positions of the hydrogen atoms were localized from the difference electron density maps and the distances were geometrically constrained. The H atoms bound to the C atoms, with d(C—H) = 0.93Å and Uiso(H) = 1.2Ueq(C) for aromatic, d(C—H) = 0.97Å and Uiso(H) = 1.2Ueq(C) for methylene.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with the atom numbering scheme. The displacement ellipsoids are drawn at 30% probability level. H atoms are presented as a small spheres of arbitrary radius.
[Figure 2] Fig. 2. The crystal packing of the title compound, viewed down b–axis, showing C2—H2···O1i hydrogen bonds. The symmetry code: (i) -1/2+x, y, 1/2-z.
7H-[1,2]Benzothiazolo[3,2-b]quinazoline 5,5-dioxide top
Crystal data top
C14H10N2O2SF(000) = 1120
Mr = 270.31Dx = 1.509 Mg m3
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 2328 reflections
a = 7.9389 (2) Åθ = 3.1–26.0°
b = 13.1460 (4) ŵ = 0.27 mm1
c = 22.7952 (7) ÅT = 295 K
V = 2379.02 (12) Å3Block, yellow
Z = 80.30 × 0.25 × 0.20 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2328 independent reflections
Radiation source: fine–focus sealed tube1981 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
ω– & ϕ–scansθmax = 26.0°, θmin = 3.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 96
Tmin = 0.922, Tmax = 0.947k = 1614
21710 measured reflectionsl = 2828
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)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.122H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.0837P)2 + 0.4043P]
where P = (Fo2 + 2Fc2)/3
2328 reflections(Δ/σ)max = 0.001
172 parametersΔρmax = 0.25 e Å3
0 restraintsΔρmin = 0.33 e Å3
Crystal data top
C14H10N2O2SV = 2379.02 (12) Å3
Mr = 270.31Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 7.9389 (2) ŵ = 0.27 mm1
b = 13.1460 (4) ÅT = 295 K
c = 22.7952 (7) Å0.30 × 0.25 × 0.20 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2328 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
1981 reflections with I > 2σ(I)
Tmin = 0.922, Tmax = 0.947Rint = 0.028
21710 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0340 restraints
wR(F2) = 0.122H-atom parameters constrained
S = 1.06Δρmax = 0.25 e Å3
2328 reflectionsΔρmin = 0.33 e Å3
172 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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
C10.0174 (2)0.49618 (13)0.32511 (7)0.0390 (4)
C20.0613 (2)0.51583 (15)0.27215 (8)0.0506 (5)
H20.07320.46550.24380.061*
C30.1217 (3)0.61328 (16)0.26314 (9)0.0556 (5)
H30.17670.62880.22830.067*
C40.1014 (2)0.68776 (16)0.30527 (9)0.0532 (5)
H40.14210.75290.29810.064*
C50.0215 (2)0.66715 (14)0.35795 (8)0.0447 (4)
H50.00840.71770.38610.054*
C60.0382 (2)0.56991 (12)0.36773 (7)0.0354 (4)
C70.12413 (19)0.53087 (11)0.42037 (7)0.0335 (4)
C80.2162 (3)0.36384 (13)0.46019 (8)0.0457 (4)
H8A0.30270.31700.44710.055*
H8B0.12060.32440.47380.055*
C90.2830 (2)0.42841 (13)0.50934 (7)0.0365 (4)
C100.24723 (19)0.53228 (12)0.51127 (6)0.0342 (4)
C110.3012 (2)0.58936 (14)0.55898 (7)0.0433 (4)
H110.27740.65860.56050.052*
C120.3900 (2)0.54436 (16)0.60411 (8)0.0497 (5)
H120.42480.58320.63600.060*
C130.4270 (2)0.44222 (16)0.60202 (8)0.0498 (5)
H130.48720.41190.63230.060*
C140.3743 (2)0.38476 (13)0.55469 (8)0.0449 (4)
H140.40040.31580.55320.054*
N10.1652 (2)0.42909 (10)0.41195 (6)0.0414 (4)
N20.15773 (18)0.58305 (10)0.46603 (6)0.0371 (3)
O10.24864 (17)0.35324 (11)0.31425 (6)0.0575 (4)
O20.01803 (19)0.30315 (10)0.35705 (6)0.0581 (4)
S10.10439 (6)0.38070 (3)0.348166 (18)0.04023 (19)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0408 (9)0.0411 (9)0.0352 (9)0.0072 (7)0.0019 (7)0.0004 (6)
C20.0551 (11)0.0603 (11)0.0363 (9)0.0090 (10)0.0058 (8)0.0043 (8)
C30.0545 (12)0.0697 (13)0.0425 (10)0.0024 (10)0.0114 (8)0.0090 (9)
C40.0570 (12)0.0512 (11)0.0514 (11)0.0031 (9)0.0086 (8)0.0096 (9)
C50.0487 (10)0.0390 (9)0.0464 (9)0.0016 (8)0.0060 (8)0.0006 (7)
C60.0359 (8)0.0360 (8)0.0343 (8)0.0053 (7)0.0003 (6)0.0003 (6)
C70.0338 (8)0.0296 (7)0.0373 (8)0.0023 (6)0.0014 (6)0.0002 (6)
C80.0606 (11)0.0329 (8)0.0436 (9)0.0040 (8)0.0039 (8)0.0006 (7)
C90.0351 (8)0.0373 (8)0.0370 (8)0.0003 (7)0.0051 (6)0.0029 (6)
C100.0322 (8)0.0360 (8)0.0345 (8)0.0005 (7)0.0016 (6)0.0005 (6)
C110.0472 (10)0.0428 (9)0.0401 (9)0.0004 (8)0.0019 (7)0.0042 (7)
C120.0515 (11)0.0588 (12)0.0387 (9)0.0042 (9)0.0051 (8)0.0030 (8)
C130.0481 (10)0.0595 (12)0.0418 (9)0.0005 (9)0.0062 (8)0.0107 (8)
C140.0456 (10)0.0424 (10)0.0468 (10)0.0029 (8)0.0014 (8)0.0085 (7)
N10.0576 (9)0.0303 (7)0.0362 (7)0.0016 (7)0.0044 (6)0.0028 (5)
N20.0417 (7)0.0335 (7)0.0363 (7)0.0022 (6)0.0034 (6)0.0021 (5)
O10.0659 (9)0.0564 (8)0.0501 (8)0.0070 (7)0.0156 (6)0.0062 (6)
O20.0750 (10)0.0423 (7)0.0570 (8)0.0208 (7)0.0046 (7)0.0050 (6)
S10.0516 (3)0.0345 (3)0.0346 (3)0.00603 (18)0.00492 (17)0.00507 (14)
Geometric parameters (Å, º) top
C1—C61.382 (2)C8—H8A0.9700
C1—C21.384 (2)C8—H8B0.9700
C1—S11.7485 (18)C9—C141.387 (2)
C2—C31.383 (3)C9—C101.395 (2)
C2—H20.9300C10—C111.389 (2)
C3—C41.381 (3)C10—N21.419 (2)
C3—H30.9300C11—C121.380 (3)
C4—C51.384 (2)C11—H110.9300
C4—H40.9300C12—C131.375 (3)
C5—C61.382 (2)C12—H120.9300
C5—H50.9300C13—C141.382 (3)
C6—C71.473 (2)C13—H130.9300
C7—N21.275 (2)C14—H140.9300
C7—N11.390 (2)N1—S11.6589 (14)
C8—N11.452 (2)O1—S11.4281 (13)
C8—C91.502 (2)O2—S11.4230 (13)
C6—C1—C2122.42 (17)C14—C9—C8120.43 (16)
C6—C1—S1110.51 (12)C10—C9—C8120.31 (14)
C2—C1—S1127.06 (14)C11—C10—C9119.36 (15)
C3—C2—C1117.32 (18)C11—C10—N2118.00 (14)
C3—C2—H2121.3C9—C10—N2122.63 (14)
C1—C2—H2121.3C12—C11—C10120.64 (17)
C2—C3—C4120.86 (18)C12—C11—H11119.7
C2—C3—H3119.6C10—C11—H11119.7
C4—C3—H3119.6C13—C12—C11120.12 (17)
C3—C4—C5121.19 (18)C13—C12—H12119.9
C3—C4—H4119.4C11—C12—H12119.9
C5—C4—H4119.4C12—C13—C14119.74 (16)
C6—C5—C4118.57 (17)C12—C13—H13120.1
C6—C5—H5120.7C14—C13—H13120.1
C4—C5—H5120.7C13—C14—C9120.93 (16)
C1—C6—C5119.62 (15)C13—C14—H14119.5
C1—C6—C7112.56 (14)C9—C14—H14119.5
C5—C6—C7127.81 (15)C7—N1—C8121.96 (13)
N2—C7—N1125.55 (14)C7—N1—S1114.95 (11)
N2—C7—C6125.08 (14)C8—N1—S1121.22 (11)
N1—C7—C6109.36 (13)C7—N2—C10116.43 (13)
N1—C8—C9109.23 (14)O2—S1—O1116.34 (9)
N1—C8—H8A109.8O2—S1—N1110.41 (8)
C9—C8—H8A109.8O1—S1—N1109.76 (8)
N1—C8—H8B109.8O2—S1—C1113.27 (9)
C9—C8—H8B109.8O1—S1—C1111.92 (8)
H8A—C8—H8B108.3N1—S1—C192.60 (7)
C14—C9—C10119.20 (15)
C6—C1—C2—C30.7 (3)C12—C13—C14—C90.6 (3)
S1—C1—C2—C3179.80 (15)C10—C9—C14—C131.3 (3)
C1—C2—C3—C40.9 (3)C8—C9—C14—C13175.78 (16)
C2—C3—C4—C50.6 (3)N2—C7—N1—C815.1 (3)
C3—C4—C5—C60.1 (3)C6—C7—N1—C8165.98 (16)
C2—C1—C6—C50.2 (3)N2—C7—N1—S1179.66 (14)
S1—C1—C6—C5179.80 (13)C6—C7—N1—S11.41 (17)
C2—C1—C6—C7179.50 (15)C9—C8—N1—C722.8 (2)
S1—C1—C6—C70.94 (18)C9—C8—N1—S1173.54 (12)
C4—C5—C6—C10.1 (3)N1—C7—N2—C101.1 (2)
C4—C5—C6—C7179.04 (16)C6—C7—N2—C10177.62 (13)
C1—C6—C7—N2179.58 (16)C11—C10—N2—C7173.48 (15)
C5—C6—C7—N20.4 (3)C9—C10—N2—C76.2 (2)
C1—C6—C7—N11.48 (19)C7—N1—S1—O2115.25 (13)
C5—C6—C7—N1179.33 (16)C8—N1—S1—O249.45 (17)
N1—C8—C9—C14165.40 (15)C7—N1—S1—O1115.20 (13)
N1—C8—C9—C1017.6 (2)C8—N1—S1—O180.10 (16)
C14—C9—C10—C111.1 (2)C7—N1—S1—C10.78 (14)
C8—C9—C10—C11175.98 (16)C8—N1—S1—C1165.48 (15)
C14—C9—C10—N2178.63 (15)C6—C1—S1—O2113.68 (13)
C8—C9—C10—N24.3 (2)C2—C1—S1—O266.78 (18)
C9—C10—C11—C120.2 (3)C6—C1—S1—O1112.40 (13)
N2—C10—C11—C12179.50 (15)C2—C1—S1—O167.14 (18)
C10—C11—C12—C130.5 (3)C6—C1—S1—N10.13 (14)
C11—C12—C13—C140.3 (3)C2—C1—S1—N1179.66 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O1i0.932.433.275 (2)150
Symmetry code: (i) x1/2, y, z+1/2.

Experimental details

Crystal data
Chemical formulaC14H10N2O2S
Mr270.31
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)295
a, b, c (Å)7.9389 (2), 13.1460 (4), 22.7952 (7)
V3)2379.02 (12)
Z8
Radiation typeMo Kα
µ (mm1)0.27
Crystal size (mm)0.30 × 0.25 × 0.20
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.922, 0.947
No. of measured, independent and
observed [I > 2σ(I)] reflections
21710, 2328, 1981
Rint0.028
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.034, 0.122, 1.06
No. of reflections2328
No. of parameters172
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.25, 0.33

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O1i0.932.433.275 (2)150.2
Symmetry code: (i) x1/2, y, z+1/2.
 

Acknowledgements

The authors thank Dr Babu Varghese, Senior Scientific Officer, SAIF, IIT, Chennai, India, for the data collection. They also thank the University Grant Commission (UGC) for funding the minor project [Ref. No. F. MRP–3640/11 (SERO–UGC)] under which this work has been carried out.

References

First citationBruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.
First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals
First citationGrundt, P., Douglas, K. A., Krivogorsky, B. & Nemykin, V. N. (2010). Acta Cryst. E66, o1474–o1475.  Web of Science CSD CrossRef IUCr Journals
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