organic compounds
Methyl 3-oxo-2,3-dihydro-1,2-benzothiazole-2-acetate 1,1-dioxide
aDepartment of Chemistry, University of Sargodha, Sargodha, Pakistan, bDepartment of Chemistry, University of Science and Technology, Bannu, Pakistan, cInstitute of Chemistry, University of the Punjab, Lahore, Pakistan, dDepartment of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4, and eDepartment of Chemistry, University of Balochistan, Quetta, Pakistan
*Correspondence e-mail: waseeq_786@yahoo.com
The title molecule, C10H9NO5S, is composed of two essentially planar units with a dihedral angle of 89.16 (6)° between them. In the there are weak intermolecular C—H⋯O interactions resulting in dimeric pairs of molecules about inversion centres and chains of molecules extended along the a and c axes, thus stabilizing the structure. In addition, benzothiazole rings lying parallel to each other with centroid–centroid distances of 3.679 (2) and 3.999 (2) Å indicate the existence of π–π stacking interactions.
Related literature
For related literature, see: Kapui et al. (2003); Masashi et al. (1999); Manjarrez et al. (1996); Siddiqui, Ahmad, Khan, Siddiqui & Parvez (2007); Siddiqui, Ahmad, Khan, Siddiqui & Weaver (2007); Siddiqui, Ahmad, Siddiqui et al. (2007); Siddiqui et al. (2008); Xu et al. (2005, 2006).
Experimental
Crystal data
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Refinement
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Data collection: COLLECT (Hooft, 1998); cell DENZO (Otwinowski & Minor, 1997); data reduction: SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SAPI91 (Fan, 1991); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S1600536808009951/lh2607sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536808009951/lh2607Isup2.hkl
The compound (I) was prepared following the prcedures reported earlier (Manjarrez et al., 1996). Crystals suitable for X-ray crystallography were grown from a solution of CH3OH by slow evaporation at 313 K.
H-atoms were included in the refinements at geometrically idealized positions with aryl, methylene and methyl C—H distances 0.95, 0.99 and 0.98 Å, respectively, and Uiso = 1.2 times Ueq of the atoms to which they were bonded. The final difference map was free of any chemically significant features.
Data collection: COLLECT (Hooft, 1998); cell
DENZO (Otwinowski & Minor, 1997); data reduction: SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SAPI91 (Fan, 1991); 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).C10H9NO5S | Z = 2 |
Mr = 255.24 | F(000) = 264 |
Triclinic, P1 | Dx = 1.550 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.765 (3) Å | Cell parameters from 4654 reflections |
b = 8.496 (3) Å | θ = 3.9–27.4° |
c = 8.776 (4) Å | µ = 0.31 mm−1 |
α = 104.39 (2)° | T = 173 K |
β = 100.58 (2)° | Block, colourless |
γ = 94.30 (2)° | 0.16 × 0.10 × 0.08 mm |
V = 546.8 (4) Å3 |
Nonius KappaCCD diffractometer | 2468 independent reflections |
Radiation source: fine-focus sealed tube | 2040 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
ω and ϕ scans | θmax = 27.4°, θmin = 3.9° |
Absorption correction: multi-scan (SORTAV; Blessing, 1997) | h = −10→9 |
Tmin = 0.953, Tmax = 0.976 | k = −11→10 |
4654 measured reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.040 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.111 | H-atom parameters constrained |
S = 1.03 | w = 1/[σ2(Fo2) + (0.056P)2 + 0.29P] where P = (Fo2 + 2Fc2)/3 |
2468 reflections | (Δ/σ)max < 0.001 |
155 parameters | Δρmax = 0.46 e Å−3 |
0 restraints | Δρmin = −0.43 e Å−3 |
C10H9NO5S | γ = 94.30 (2)° |
Mr = 255.24 | V = 546.8 (4) Å3 |
Triclinic, P1 | Z = 2 |
a = 7.765 (3) Å | Mo Kα radiation |
b = 8.496 (3) Å | µ = 0.31 mm−1 |
c = 8.776 (4) Å | T = 173 K |
α = 104.39 (2)° | 0.16 × 0.10 × 0.08 mm |
β = 100.58 (2)° |
Nonius KappaCCD diffractometer | 2468 independent reflections |
Absorption correction: multi-scan (SORTAV; Blessing, 1997) | 2040 reflections with I > 2σ(I) |
Tmin = 0.953, Tmax = 0.976 | Rint = 0.024 |
4654 measured reflections |
R[F2 > 2σ(F2)] = 0.040 | 0 restraints |
wR(F2) = 0.111 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.46 e Å−3 |
2468 reflections | Δρmin = −0.43 e Å−3 |
155 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. |
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. |
x | y | z | Uiso*/Ueq | ||
S1 | 0.25284 (6) | 0.37128 (6) | 1.06522 (6) | 0.02602 (16) | |
O1 | −0.07412 (18) | 0.18372 (19) | 0.67891 (17) | 0.0354 (3) | |
O2 | 0.40672 (17) | 0.29152 (17) | 1.08988 (17) | 0.0320 (3) | |
O3 | 0.2727 (2) | 0.54422 (17) | 1.13620 (18) | 0.0372 (4) | |
O4 | 0.3882 (2) | 0.14876 (17) | 0.70088 (18) | 0.0369 (4) | |
O5 | 0.41016 (18) | 0.33528 (17) | 0.56027 (16) | 0.0312 (3) | |
N1 | 0.1635 (2) | 0.3311 (2) | 0.87005 (18) | 0.0275 (4) | |
C1 | 0.0687 (2) | 0.2676 (2) | 1.1032 (2) | 0.0243 (4) | |
C2 | 0.0451 (3) | 0.2516 (2) | 1.2517 (2) | 0.0303 (4) | |
H2 | 0.1321 | 0.2987 | 1.3471 | 0.036* | |
C3 | −0.1118 (3) | 0.1633 (3) | 1.2543 (3) | 0.0325 (4) | |
H3 | −0.1321 | 0.1482 | 1.3535 | 0.039* | |
C4 | −0.2397 (3) | 0.0968 (2) | 1.1148 (3) | 0.0329 (5) | |
H4 | −0.3467 | 0.0384 | 1.1202 | 0.040* | |
C5 | −0.2128 (3) | 0.1147 (2) | 0.9669 (2) | 0.0297 (4) | |
H5 | −0.3005 | 0.0698 | 0.8716 | 0.036* | |
C6 | −0.0558 (2) | 0.1990 (2) | 0.9619 (2) | 0.0245 (4) | |
C7 | −0.0003 (2) | 0.2326 (2) | 0.8179 (2) | 0.0263 (4) | |
C8 | 0.2499 (3) | 0.3960 (2) | 0.7616 (2) | 0.0292 (4) | |
H8A | 0.3291 | 0.4972 | 0.8238 | 0.035* | |
H8B | 0.1593 | 0.4256 | 0.6819 | 0.035* | |
C9 | 0.3566 (2) | 0.2757 (2) | 0.6733 (2) | 0.0268 (4) | |
C10 | 0.5248 (3) | 0.2391 (3) | 0.4726 (3) | 0.0435 (6) | |
H10A | 0.5553 | 0.2910 | 0.3914 | 0.052* | |
H10B | 0.4638 | 0.1284 | 0.4195 | 0.052* | |
H10C | 0.6329 | 0.2329 | 0.5475 | 0.052* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0241 (3) | 0.0292 (3) | 0.0245 (3) | 0.00447 (18) | 0.00385 (18) | 0.00737 (18) |
O1 | 0.0311 (7) | 0.0495 (9) | 0.0236 (7) | 0.0080 (6) | 0.0024 (6) | 0.0076 (6) |
O2 | 0.0225 (7) | 0.0398 (8) | 0.0339 (8) | 0.0068 (6) | 0.0027 (6) | 0.0117 (6) |
O3 | 0.0426 (9) | 0.0266 (7) | 0.0379 (8) | 0.0026 (6) | 0.0035 (7) | 0.0045 (6) |
O4 | 0.0472 (9) | 0.0316 (8) | 0.0378 (8) | 0.0101 (7) | 0.0158 (7) | 0.0136 (6) |
O5 | 0.0308 (7) | 0.0441 (8) | 0.0252 (7) | 0.0126 (6) | 0.0102 (6) | 0.0158 (6) |
N1 | 0.0242 (8) | 0.0376 (9) | 0.0217 (8) | 0.0022 (7) | 0.0048 (6) | 0.0102 (7) |
C1 | 0.0226 (9) | 0.0270 (9) | 0.0251 (9) | 0.0069 (7) | 0.0061 (7) | 0.0083 (7) |
C2 | 0.0307 (10) | 0.0375 (11) | 0.0241 (10) | 0.0094 (8) | 0.0053 (8) | 0.0095 (8) |
C3 | 0.0377 (11) | 0.0375 (11) | 0.0309 (11) | 0.0155 (9) | 0.0161 (9) | 0.0151 (8) |
C4 | 0.0269 (10) | 0.0328 (10) | 0.0452 (12) | 0.0065 (8) | 0.0137 (9) | 0.0164 (9) |
C5 | 0.0245 (9) | 0.0314 (10) | 0.0328 (10) | 0.0046 (8) | 0.0035 (8) | 0.0095 (8) |
C6 | 0.0252 (9) | 0.0248 (9) | 0.0240 (9) | 0.0086 (7) | 0.0042 (7) | 0.0066 (7) |
C7 | 0.0261 (9) | 0.0288 (9) | 0.0237 (10) | 0.0051 (7) | 0.0073 (7) | 0.0042 (7) |
C8 | 0.0305 (10) | 0.0329 (10) | 0.0297 (10) | 0.0075 (8) | 0.0115 (8) | 0.0135 (8) |
C9 | 0.0230 (9) | 0.0325 (10) | 0.0243 (9) | 0.0000 (7) | 0.0032 (7) | 0.0090 (8) |
C10 | 0.0436 (13) | 0.0656 (15) | 0.0302 (11) | 0.0250 (11) | 0.0173 (10) | 0.0169 (10) |
S1—O2 | 1.4258 (15) | C3—C4 | 1.389 (3) |
S1—O3 | 1.4306 (15) | C3—H3 | 0.9500 |
S1—N1 | 1.6640 (18) | C4—C5 | 1.395 (3) |
S1—C1 | 1.7504 (19) | C4—H4 | 0.9500 |
O1—C7 | 1.202 (2) | C5—C6 | 1.380 (3) |
O4—C9 | 1.196 (2) | C5—H5 | 0.9500 |
O5—C9 | 1.335 (2) | C6—C7 | 1.492 (3) |
O5—C10 | 1.449 (2) | C8—C9 | 1.517 (3) |
N1—C7 | 1.402 (3) | C8—H8A | 0.9900 |
N1—C8 | 1.449 (2) | C8—H8B | 0.9900 |
C1—C2 | 1.387 (3) | C10—H10A | 0.9800 |
C1—C6 | 1.388 (3) | C10—H10B | 0.9800 |
C2—C3 | 1.389 (3) | C10—H10C | 0.9800 |
C2—H2 | 0.9500 | ||
O2—S1—O3 | 116.71 (9) | C6—C5—H5 | 120.7 |
O2—S1—N1 | 110.73 (9) | C4—C5—H5 | 120.7 |
O3—S1—N1 | 109.35 (9) | C5—C6—C1 | 119.81 (18) |
O2—S1—C1 | 112.26 (9) | C5—C6—C7 | 127.38 (17) |
O3—S1—C1 | 112.83 (9) | C1—C6—C7 | 112.78 (17) |
N1—S1—C1 | 92.26 (9) | O1—C7—N1 | 123.33 (18) |
C9—O5—C10 | 115.33 (16) | O1—C7—C6 | 128.71 (18) |
C7—N1—C8 | 122.31 (16) | N1—C7—C6 | 107.93 (16) |
C7—N1—S1 | 116.00 (13) | N1—C8—C9 | 112.82 (16) |
C8—N1—S1 | 121.68 (13) | N1—C8—H8A | 109.0 |
C2—C1—C6 | 122.73 (18) | C9—C8—H8A | 109.0 |
C2—C1—S1 | 126.37 (15) | N1—C8—H8B | 109.0 |
C6—C1—S1 | 110.90 (14) | C9—C8—H8B | 109.0 |
C1—C2—C3 | 116.80 (19) | H8A—C8—H8B | 107.8 |
C1—C2—H2 | 121.6 | O4—C9—O5 | 125.61 (18) |
C3—C2—H2 | 121.6 | O4—C9—C8 | 125.59 (18) |
C2—C3—C4 | 121.34 (19) | O5—C9—C8 | 108.80 (16) |
C2—C3—H3 | 119.3 | O5—C10—H10A | 109.5 |
C4—C3—H3 | 119.3 | O5—C10—H10B | 109.5 |
C3—C4—C5 | 120.73 (19) | H10A—C10—H10B | 109.5 |
C3—C4—H4 | 119.6 | O5—C10—H10C | 109.5 |
C5—C4—H4 | 119.6 | H10A—C10—H10C | 109.5 |
C6—C5—C4 | 118.57 (18) | H10B—C10—H10C | 109.5 |
O2—S1—N1—C7 | 111.37 (15) | C2—C1—C6—C5 | 1.8 (3) |
O3—S1—N1—C7 | −118.66 (15) | S1—C1—C6—C5 | −178.65 (14) |
C1—S1—N1—C7 | −3.48 (15) | C2—C1—C6—C7 | −179.84 (17) |
O2—S1—N1—C8 | −69.24 (17) | S1—C1—C6—C7 | −0.3 (2) |
O3—S1—N1—C8 | 60.73 (17) | C8—N1—C7—O1 | 6.2 (3) |
C1—S1—N1—C8 | 175.91 (15) | S1—N1—C7—O1 | −174.37 (15) |
O2—S1—C1—C2 | 68.07 (19) | C8—N1—C7—C6 | −175.64 (16) |
O3—S1—C1—C2 | −66.31 (19) | S1—N1—C7—C6 | 3.7 (2) |
N1—S1—C1—C2 | −178.43 (18) | C5—C6—C7—O1 | −5.9 (3) |
O2—S1—C1—C6 | −111.44 (14) | C1—C6—C7—O1 | 175.94 (19) |
O3—S1—C1—C6 | 114.19 (14) | C5—C6—C7—N1 | 176.14 (18) |
N1—S1—C1—C6 | 2.07 (14) | C1—C6—C7—N1 | −2.0 (2) |
C6—C1—C2—C3 | −0.4 (3) | C7—N1—C8—C9 | −84.4 (2) |
S1—C1—C2—C3 | −179.86 (15) | S1—N1—C8—C9 | 96.29 (18) |
C1—C2—C3—C4 | −1.0 (3) | C10—O5—C9—O4 | −3.8 (3) |
C2—C3—C4—C5 | 1.0 (3) | C10—O5—C9—C8 | 175.82 (16) |
C3—C4—C5—C6 | 0.4 (3) | N1—C8—C9—O4 | −9.1 (3) |
C4—C5—C6—C1 | −1.8 (3) | N1—C8—C9—O5 | 171.21 (15) |
C4—C5—C6—C7 | −179.84 (17) |
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H2···O5i | 0.95 | 2.53 | 3.435 (3) | 160 |
C4—H4···O4ii | 0.95 | 2.54 | 3.209 (3) | 128 |
C8—H8A···O2iii | 0.99 | 2.49 | 3.435 (3) | 159 |
C10—H10C···O1iv | 0.98 | 2.47 | 3.431 (3) | 167 |
Symmetry codes: (i) x, y, z+1; (ii) −x, −y, −z+2; (iii) −x+1, −y+1, −z+2; (iv) x+1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C10H9NO5S |
Mr | 255.24 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 173 |
a, b, c (Å) | 7.765 (3), 8.496 (3), 8.776 (4) |
α, β, γ (°) | 104.39 (2), 100.58 (2), 94.30 (2) |
V (Å3) | 546.8 (4) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.31 |
Crystal size (mm) | 0.16 × 0.10 × 0.08 |
Data collection | |
Diffractometer | Nonius KappaCCD diffractometer |
Absorption correction | Multi-scan (SORTAV; Blessing, 1997) |
Tmin, Tmax | 0.953, 0.976 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 4654, 2468, 2040 |
Rint | 0.024 |
(sin θ/λ)max (Å−1) | 0.647 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.040, 0.111, 1.03 |
No. of reflections | 2468 |
No. of parameters | 155 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.46, −0.43 |
Computer programs: COLLECT (Hooft, 1998), DENZO (Otwinowski & Minor, 1997), SCALEPACK (Otwinowski & Minor, 1997), SAPI91 (Fan, 1991), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H2···O5i | 0.95 | 2.53 | 3.435 (3) | 160 |
C4—H4···O4ii | 0.95 | 2.54 | 3.209 (3) | 128 |
C8—H8A···O2iii | 0.99 | 2.49 | 3.435 (3) | 159 |
C10—H10C···O1iv | 0.98 | 2.47 | 3.431 (3) | 167 |
Symmetry codes: (i) x, y, z+1; (ii) −x, −y, −z+2; (iii) −x+1, −y+1, −z+2; (iv) x+1, y, z. |
References
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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
Saccharin derivatives are considered to be the most potent orally active human leucocyte elastase (HLE) inhibitors for the treatment of chronic obstructive pulmonary disease (COPD), acute respiratory distress syndrome (ARDS), cystic fibrosis, asthma and other inflammatory diseases (Kapui et al., 2003). Various biologically important saccharin skeletons and their N-alkyl derivatives were efficiently prepared (Xu et al., 2006) by chromium oxide-catalyzed oxidation of N-alkyl(o-methyl)arenesulfonamides in acetonitrile besides the already developed methodology utilizing irradiation techniques for similar type of conversions (Masashi et al., 1999). In continuation to our research on benzene, 1,2-benzothiazine 1,1-dioxide and saccharin derivatives (Siddiqui et al., 2008; Siddiqui, Ahmad, Khan, Siddiqui & Weaver, 2007), we report herein the crystal structure of the title compound, (I).
The structure of (I) is composed of an essentially planar moiety, S1/N1/O1/C1—C7 with maximum deviations from the least-square planes being: O1 = -0.0540 (12) and N1 = 0.0540 (13) Å, and an approximately planar moiety C8—C10/O4/O5 with maximum deviation of 0.0766 (13) Å for C8. The two moieties are oriented with a dihedral angle of 89.16 (6)° between their least-squares planes. The structure is stabilized by four rather weak intermolecular interactions of the type C—H···O (Fig. 2 and Table 1). Of these interactions, C4—H4···O5 and C8—H8A···O2 H-bonds result in dimeric pairs of (I) while C10—H10···O1 and C2—H2···O5 result in chains of molecules extended along the a- and c-axes, respectively. The benzothiazole rings in (I) lie parallel to each other about the origin with the shortest distance between the centroids of the benzene rings of the adjacent molecules is 3.679 (2) Å which indicates the existence of π-π stacking interactions. The thiazoline rings located about inversion centers in the middle of the b axis (at 0, 1/2, 0) also show π-π interaction with centroids of these rings separated by 3.999 (2) Å (Fig. 3). The molecular dimensions in (I) are in agreement with the corresponding dimensions reported in similar structures (Xu et al., 2005; Siddiqui, Ahmad, Khan, Siddiqui & Parvez, 2007; Siddiqui, Ahmad, Siddiqui et al., 2007; Siddiqui et al., 2008).