organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

3-(6-Fluoro-4-oxo-4H-chromen-3-yl)-3,4-di­hydro-2H-1,2,4-benzo­thia­diazine-1,1-dione

aInstitute of Chemistry, University of the Punjab, Lahore, Pakistan, bDepartment of Chemistry, Government College University, Lahore, Pakistan, and cInstitute of Inorganic Chemistry, Karlsruhe Institute of Technology, D-76133 Karlsruhe, Germany
*Correspondence e-mail: abbas191@gmail.com

(Received 7 September 2010; accepted 24 September 2010; online 2 October 2010)

In the title compound, C16H11FN2O4S, the mean planes of the bicyclic chromone system and of the benzene ring of the benzothia­diazine derivative make a dihedral angle of 54.28 (5)°. An intra­molecular N—H⋯O hydrogen bond occurs. In the crystal, mol­ecules are linked into layers by N—H⋯O and C—H⋯O hydrogen bonds, generating an infinite two-dimensional network.

Related literature

For background to the importance of the 1,2,4-benzothia­diazine-1,1-dioxide ring system in pharmaceutical and medicinal chemistry, see: Zhu et al. (2005[Zhu, Z., Zhu, S., Liu, D., Cao, T., Wang, L. & Tepel, M. (2005). Hypertension, 45, 233-239.]); Kamal et al. (2007a[Kamal, A., Ahmed, S. K., Reddy, K. S., Khan, M. N. A., Shetty, R. V. C. R. N. C., Siddhardha, B., Murty, U. S. N., China, A. & Nagaraja, V. (2007a). Lett. Drug Des. Discov. 4, 550-556.]). For a survey on the anti­microbial activity of benzothia­diazine derivatives, see: Di Bella et al. (1983[Di Bella, M., Monzani, A., Andrisano, M. G., Fabio, U. & Quaglio, G. P. (1983). Farmaco, 38, 466-472.]); Kamal et al. (2007a[Kamal, A., Ahmed, S. K., Reddy, K. S., Khan, M. N. A., Shetty, R. V. C. R. N. C., Siddhardha, B., Murty, U. S. N., China, A. & Nagaraja, V. (2007a). Lett. Drug Des. Discov. 4, 550-556.],b[Kamal, A., Khan, M. N. A., Reddy, K. S., Rohini, K., Sastry, G. N., Sateesh, B. & Sridhar, B. (2007b). Bioorg. Med. Chem. Lett. 17, 5400-5405.]). The sulfonamide group is an active pharmacophore, see: Weisman & Brown (1964[Weisman, R. A. & Brown, G. M. (1964). J. Biol. Chem. 239, 326-331.]). For a related structure, see: Mariya-al-Rashida et al. (2009[Mariya-al-Rashida, Tahir, M. N., Nagra, S. A., Imran, M. & Iqbal, J. (2009). Acta Cryst. E65, o1818-o1819.]);

[Scheme 1]

Experimental

Crystal data
  • C16H11FN2O4S

  • Mr = 346.34

  • Orthorhombic, P 21 21 21

  • a = 7.0739 (3) Å

  • b = 8.2861 (4) Å

  • c = 25.0456 (12) Å

  • V = 1468.05 (12) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.26 mm−1

  • T = 296 K

  • 0.31 × 0.06 × 0.05 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • 9538 measured reflections

  • 3453 independent reflections

  • 1993 reflections with I > 2σ(I)

  • Rint = 0.056

Refinement
  • R[F2 > 2σ(F2)] = 0.052

  • wR(F2) = 0.093

  • S = 0.97

  • 3453 reflections

  • 223 parameters

  • 3 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.28 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1345 Friedel pairs

  • Flack parameter: 0.01 (9)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N4—H4A⋯O3i 0.85 (3) 2.21 (3) 2.993 (3) 153 (3)
N4—H4A⋯O4 0.85 (3) 2.39 (3) 2.924 (3) 121 (3)
N2—H2A⋯O4ii 0.88 (3) 2.03 (3) 2.848 (3) 155 (3)
C2—H2⋯O2iii 0.93 2.48 3.399 (4) 168
C13—H13⋯O3i 0.93 2.49 3.258 (3) 140
Symmetry codes: (i) x+1, y, z; (ii) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) [-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. 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 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); 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 1,2,4-benzothiadiazine-1,1-dioxide ring system has attained considerable importance in pharmaceutical and medicinal chemistry mainly due to the compounds such as chlorothiazide and diazoxide (Zhu et al., 2005; Kamal et al., 2007a). The sulfonamide group is an active pharmacophore which is responsible for many biological activities (Weisman & Brown, 1964). The crystal structure of the condensation product of 4-aminobenzenesulfonamide with 4-oxo-4H-1-benzopyran-3-carboxaldehyde has previously been reported (al-Rashida et al., 2009). Herein, we report the crystal structure of the condensation product of 2-aminobenzenesulfonamide with 6-fluoro-4-oxo-4H-1-benzopyran-3-carboxaldehyde.

In the molecule of the title compound (Fig. 1), the two rings of the chromone system (F1, O1, O4, C2—C10) are coplanar, making a dihedral angle of 0.55 (19)°. The carbon atom C11 deviates only by 0.034 (5) Å from the mean plane of the chromone. The phenyl ring (C12—C17) and the atoms N4, S1 and C11 are coplanar as well (rms deviation = 0.033) and make a dihedral angle of 54.28 (5)° with the mean plane of the chromone system.

The crystal structure is stabilized by intra- and intermolecular N—H···O and C—H···O hydrogen bonds which link the molecules into an infinite two-dimensional network (Fig. 2).

Related literature top

For background to the importance of the 1,2,4-benzothiadiazine-1,1-dioxide ring system in pharmaceutical and medicinal chemistry, see: Zhu et al. (2005); Kamal et al. (2007a). For a survey on the antimicrobial activity of benzothiadiazine derivatives, see: Di Bella et al. (1983); Kamal et al. (2007a,b). The sulfonamide group is an active pharmacophore which is responsible for many biological activities, see: Weisman & Brown (1964). For a related structure, see: Mariya-al-Rashida et al. (2009);

Experimental top

A solution of 2-aminobenzenesulfonamide (1.0 mmol) in 10 ml ethanol was slowly added to the stirred solution of 6-fluoro-4-oxo-4H-1-benzopyran-3-carboxaldehyde (1.0 mmol) containing a catalytic amount of p-toluene sulfonic acid (p-TsOH) and refluxed for 3 hrs. The resulting product was isolated by filtration, washed with ethanol, dried and recrystallized from hot ethanol and acetone (1:1) (yield 81%, m.p. 472 K).

Refinement top

The H atoms attached to N were located in a difference Fourier map and their coordinates were refined, with Uiso(H) = 1.2Ueq(N). The remaining H atoms were positioned geometrically with C-H = 0.93 and 0.98 Å for aromatic and methine H atoms, respectively, and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. A packing diagram of the title compound showing hydrogen bonds as dashed lines.
3-(6-Fluoro-4-oxo-4H-chromen-3-yl)-3,4-dihydro-2H-1,2,4- benzothiadiazine-1,1-dione top
Crystal data top
C16H11FN2O4SF(000) = 712
Mr = 346.34Dx = 1.567 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 1626 reflections
a = 7.0739 (3) Åθ = 3.3–22.0°
b = 8.2861 (4) ŵ = 0.26 mm1
c = 25.0456 (12) ÅT = 296 K
V = 1468.05 (12) Å3Needle, orange
Z = 40.31 × 0.06 × 0.05 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
1993 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.056
Graphite monochromatorθmax = 28.3°, θmin = 3.0°
phi and ω scansh = 99
9538 measured reflectionsk = 1010
3453 independent reflectionsl = 3324
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)] = 0.052H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.093 w = 1/[σ2(Fo2) + (0.0318P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.97(Δ/σ)max < 0.001
3453 reflectionsΔρmax = 0.23 e Å3
223 parametersΔρmin = 0.28 e Å3
3 restraintsAbsolute structure: Flack (1983), 1345 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.01 (9)
Crystal data top
C16H11FN2O4SV = 1468.05 (12) Å3
Mr = 346.34Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 7.0739 (3) ŵ = 0.26 mm1
b = 8.2861 (4) ÅT = 296 K
c = 25.0456 (12) Å0.31 × 0.06 × 0.05 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
1993 reflections with I > 2σ(I)
9538 measured reflectionsRint = 0.056
3453 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.052H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.093Δρmax = 0.23 e Å3
S = 0.97Δρmin = 0.28 e Å3
3453 reflectionsAbsolute structure: Flack (1983), 1345 Friedel pairs
223 parametersAbsolute structure parameter: 0.01 (9)
3 restraints
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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
S10.05991 (10)0.79823 (11)0.18441 (3)0.0371 (2)
O20.0424 (3)0.9692 (3)0.18575 (10)0.0520 (6)
O30.1066 (2)0.7017 (3)0.18043 (9)0.0481 (6)
N40.4758 (3)0.7352 (4)0.19622 (11)0.0431 (8)
H4A0.593 (4)0.736 (4)0.2026 (12)0.052*
N20.1714 (3)0.7397 (3)0.23806 (11)0.0315 (7)
H2A0.167 (4)0.634 (4)0.2387 (11)0.038*
C170.2141 (4)0.7419 (4)0.13334 (13)0.0342 (8)
C160.1469 (4)0.7134 (5)0.08251 (14)0.0469 (9)
H160.01940.72950.07530.056*
C150.2643 (5)0.6619 (4)0.04245 (14)0.0551 (10)
H150.21870.64460.00810.066*
C140.4523 (5)0.6364 (5)0.05458 (13)0.0499 (10)
H140.53350.60020.02790.060*
C130.5222 (4)0.6627 (4)0.10455 (13)0.0453 (10)
H130.64960.64400.11130.054*
C120.4050 (4)0.7178 (4)0.14604 (12)0.0338 (8)
C110.3657 (4)0.8018 (4)0.24047 (12)0.0334 (7)
H110.36290.91970.23740.040*
C30.4590 (4)0.7558 (4)0.29238 (12)0.0323 (8)
C40.6462 (4)0.8218 (4)0.30203 (12)0.0297 (7)
O40.7261 (3)0.9080 (3)0.26942 (8)0.0382 (6)
C100.7285 (4)0.7785 (4)0.35354 (12)0.0314 (7)
C50.9080 (4)0.8345 (4)0.36782 (12)0.0396 (9)
H50.97780.89980.34490.048*
C60.9767 (5)0.7904 (5)0.41614 (15)0.0516 (11)
F11.1503 (3)0.8486 (3)0.43125 (8)0.0783 (8)
C70.8798 (5)0.6941 (5)0.45116 (15)0.0598 (11)
H70.93140.66900.48430.072*
C80.7072 (5)0.6355 (4)0.43699 (13)0.0539 (10)
H80.64060.56700.45960.065*
C90.6331 (4)0.6803 (4)0.38801 (13)0.0401 (8)
O10.4555 (3)0.6203 (3)0.37625 (9)0.0471 (6)
C20.3784 (4)0.6620 (4)0.32923 (13)0.0429 (9)
H20.25840.62210.32170.051*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0215 (3)0.0401 (5)0.0498 (5)0.0054 (4)0.0011 (4)0.0013 (5)
O20.0419 (12)0.0430 (15)0.0711 (17)0.0132 (11)0.0049 (13)0.0072 (15)
O30.0186 (10)0.0601 (16)0.0658 (16)0.0026 (10)0.0003 (10)0.0045 (14)
N40.0170 (12)0.075 (2)0.0377 (18)0.0037 (14)0.0000 (11)0.0042 (15)
N20.0221 (12)0.0295 (17)0.0430 (17)0.0023 (11)0.0036 (11)0.0033 (13)
C170.0262 (15)0.038 (2)0.039 (2)0.0004 (14)0.0012 (13)0.0021 (16)
C160.0346 (16)0.060 (3)0.046 (2)0.0012 (18)0.0116 (16)0.007 (2)
C150.056 (2)0.074 (3)0.035 (2)0.007 (2)0.0062 (19)0.000 (2)
C140.049 (2)0.063 (3)0.038 (2)0.001 (2)0.0073 (18)0.005 (2)
C130.0280 (17)0.063 (3)0.044 (2)0.0004 (16)0.0028 (15)0.002 (2)
C120.0215 (15)0.041 (2)0.039 (2)0.0034 (14)0.0012 (13)0.0002 (18)
C110.0238 (14)0.038 (2)0.0387 (19)0.0060 (15)0.0045 (13)0.0012 (17)
C30.0282 (14)0.035 (2)0.0341 (19)0.0021 (15)0.0062 (14)0.0030 (16)
C40.0302 (15)0.0255 (19)0.0332 (19)0.0013 (14)0.0044 (13)0.0031 (16)
O40.0351 (11)0.0418 (15)0.0376 (13)0.0113 (11)0.0007 (10)0.0056 (11)
C100.0374 (16)0.026 (2)0.0307 (18)0.0027 (16)0.0000 (14)0.0034 (16)
C50.0404 (19)0.039 (2)0.039 (2)0.0019 (15)0.0028 (15)0.0014 (17)
C60.046 (2)0.060 (3)0.048 (2)0.000 (2)0.0181 (18)0.004 (2)
F10.0598 (13)0.108 (2)0.0671 (16)0.0153 (13)0.0323 (11)0.0078 (14)
C70.077 (3)0.062 (3)0.041 (2)0.001 (2)0.016 (2)0.006 (2)
C80.075 (3)0.051 (3)0.036 (2)0.003 (2)0.0002 (19)0.0075 (19)
C90.0470 (18)0.036 (2)0.038 (2)0.0005 (17)0.0016 (17)0.0016 (19)
O10.0512 (13)0.0521 (16)0.0381 (14)0.0150 (13)0.0022 (11)0.0119 (12)
C20.0349 (16)0.048 (3)0.045 (2)0.0079 (16)0.0031 (16)0.0028 (19)
Geometric parameters (Å, º) top
S1—O21.422 (2)C11—C31.507 (4)
S1—O31.427 (2)C11—H110.9800
S1—N21.632 (3)C3—C21.335 (4)
S1—C171.745 (3)C3—C41.453 (4)
N4—C121.360 (4)C4—O41.224 (3)
N4—C111.463 (4)C4—C101.460 (4)
N4—H4A0.85 (3)C10—C91.364 (4)
N2—C111.469 (3)C10—C51.398 (4)
N2—H2A0.88 (3)C5—C61.354 (4)
C17—C161.379 (4)C5—H50.9300
C17—C121.402 (4)C6—C71.370 (5)
C16—C151.370 (5)C6—F11.373 (3)
C16—H160.9300C7—C81.361 (5)
C15—C141.380 (4)C7—H70.9300
C15—H150.9300C8—C91.385 (4)
C14—C131.363 (4)C8—H80.9300
C14—H140.9300C9—O11.383 (4)
C13—C121.406 (4)O1—C21.343 (3)
C13—H130.9300C2—H20.9300
O2—S1—O3119.19 (14)N2—C11—C3110.9 (2)
O2—S1—N2108.60 (15)N4—C11—H11109.1
O3—S1—N2106.84 (13)N2—C11—H11109.1
O2—S1—C17109.76 (14)C3—C11—H11109.1
O3—S1—C17108.36 (14)C2—C3—C4119.6 (3)
N2—S1—C17102.83 (13)C2—C3—C11123.8 (3)
C12—N4—C11122.9 (2)C4—C3—C11116.6 (3)
C12—N4—H4A122 (2)O4—C4—C3122.0 (3)
C11—N4—H4A112 (2)O4—C4—C10123.3 (3)
C11—N2—S1112.4 (2)C3—C4—C10114.7 (3)
C11—N2—H2A112.3 (19)C9—C10—C5119.0 (3)
S1—N2—H2A107.2 (19)C9—C10—C4120.5 (3)
C16—C17—C12121.1 (3)C5—C10—C4120.4 (3)
C16—C17—S1120.5 (2)C6—C5—C10117.7 (3)
C12—C17—S1118.3 (2)C6—C5—H5121.1
C15—C16—C17121.4 (3)C10—C5—H5121.1
C15—C16—H16119.3C5—C6—C7123.3 (3)
C17—C16—H16119.3C5—C6—F1118.2 (4)
C16—C15—C14118.0 (3)C7—C6—F1118.4 (3)
C16—C15—H15121.0C8—C7—C6119.3 (3)
C14—C15—H15121.0C8—C7—H7120.3
C13—C14—C15121.8 (3)C6—C7—H7120.3
C13—C14—H14119.1C7—C8—C9118.3 (3)
C15—C14—H14119.1C7—C8—H8120.8
C14—C13—C12121.1 (3)C9—C8—H8120.8
C14—C13—H13119.4C10—C9—O1121.9 (3)
C12—C13—H13119.4C10—C9—C8122.2 (3)
N4—C12—C17123.3 (3)O1—C9—C8115.8 (3)
N4—C12—C13120.0 (2)C2—O1—C9117.6 (3)
C17—C12—C13116.5 (3)C3—C2—O1125.6 (3)
N4—C11—N2109.6 (3)C3—C2—H2117.2
N4—C11—C3109.0 (2)O1—C2—H2117.2
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···O3i0.85 (3)2.21 (3)2.993 (3)153 (3)
N4—H4A···O40.85 (3)2.39 (3)2.924 (3)121 (3)
N2—H2A···O4ii0.88 (3)2.03 (3)2.848 (3)155 (3)
C2—H2···O2iii0.932.483.399 (4)168
C13—H13···O3i0.932.493.258 (3)140
Symmetry codes: (i) x+1, y, z; (ii) x+1, y1/2, z+1/2; (iii) x, y1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC16H11FN2O4S
Mr346.34
Crystal system, space groupOrthorhombic, P212121
Temperature (K)296
a, b, c (Å)7.0739 (3), 8.2861 (4), 25.0456 (12)
V3)1468.05 (12)
Z4
Radiation typeMo Kα
µ (mm1)0.26
Crystal size (mm)0.31 × 0.06 × 0.05
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
9538, 3453, 1993
Rint0.056
(sin θ/λ)max1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.052, 0.093, 0.97
No. of reflections3453
No. of parameters223
No. of restraints3
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.23, 0.28
Absolute structureFlack (1983), 1345 Friedel pairs
Absolute structure parameter0.01 (9)

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2006), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···O3i0.85 (3)2.21 (3)2.993 (3)153 (3)
N4—H4A···O40.85 (3)2.39 (3)2.924 (3)121 (3)
N2—H2A···O4ii0.88 (3)2.03 (3)2.848 (3)155 (3)
C2—H2···O2iii0.932.483.399 (4)168
C13—H13···O3i0.932.493.258 (3)140
Symmetry codes: (i) x+1, y, z; (ii) x+1, y1/2, z+1/2; (iii) x, y1/2, z+1/2.
 

Footnotes

Additional corresponding author, e-mail: maria_al_rashida@hotmail.com.

Acknowledgements

The authors acknowledge the Higher Education Commission, Islamabad, Pakistan, for financial and GCU Lahore for technical support.

References

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