organic compounds
Methyl 4-hydroxy-2-propyl-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide
aDepartment of Chemistry, Government College University, Lahore 54000, Pakistan, and bApplied Chemistry Research Centre, PCSIR Laboratories Complex, Lahore 54600, Pakistan
*Correspondence e-mail: iukhan.gcu@gmail.com
In the title compound, C13H15NO5S, the thiazine ring adopts a distorted half-chair conformation. The enolic H atom is involved in an intramolecular O—H⋯O hydrogen bond, forming a six-membered ring. In the crystal, molecules are linked through weak intermolecular C—H⋯O hydrogen bonds, resulting in zigzag chains lying along the c axis.
Related literature
For the syntheses of related compounds, see: Bihovsky et al. (2004); Braun (1923); Lombardino et al. (1971); Zia-ur-Rehman et al. (2005, 2009). For the biological activity of benzothiazines, see: Turck et al. (1996); Zia-ur-Rehman et al. (2006). For related structures, see: Fabiola et al. (1998); Zia-ur-Rehman et al. (2007).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2007); cell SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON.
Supporting information
10.1107/S1600536809046236/is2482sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809046236/is2482Isup2.hkl
Propyl iodide (5.10 g, 30.0 mmol) was added drop wise to the mixture of methyl 4-hydroxy-2H-1,2-benzothiazine-3-carboxylate-1,1-dioxide (3.83 g, 15.0 mmol), anhydrous potassium carbonate (1.68 g, 30.0 mmol) and dimethylformamide (20.0 ml) in a round bottom flask. Contents were stirred at room temperature for 7 h under nitrogen atmosphere and poured over ice cooled water (300 ml) resulting in an immediate formation of a white solid, which was filtered and washed with cold water. Crystallization from methanol yielded pure compound.
All hydrogen atoms were identified in the difference map and subsequently fixed in ideal positions and treated as riding on their parent atoms. In the case of the methyl and hydroxyl H atoms the torsion angles were freely refined. The following distances were used: C—H = 0.98 Å for methyl, C—H = 0.95 Å for aromatic and O—H = 0.84 Å for hydroxyl. Uiso(H) was set to 1.2Ueq of the parent atoms or 1.5Ueq for methyl groups.
Data collection: APEX2 (Bruker, 2007); cell
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: PLATON (Spek, 2009) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).C13H15NO5S | F(000) = 624 |
Mr = 297.32 | Dx = 1.425 Mg m−3 |
Orthorhombic, Pca21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2c -2ac | Cell parameters from 2980 reflections |
a = 12.4398 (6) Å | θ = 2.3–25.3° |
b = 8.7538 (5) Å | µ = 0.25 mm−1 |
c = 12.7288 (7) Å | T = 296 K |
V = 1386.11 (13) Å3 | Rods, yellow |
Z = 4 | 0.39 × 0.36 × 0.11 mm |
Bruker APEXII CCD area-detector diffractometer | 3252 independent reflections |
Radiation source: fine-focus sealed tube | 2540 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.028 |
ϕ and ω scans | θmax = 28.3°, θmin = 2.9° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −16→10 |
Tmin = 0.908, Tmax = 0.973 | k = −11→11 |
8843 measured reflections | l = −16→15 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.036 | H-atom parameters constrained |
wR(F2) = 0.094 | w = 1/[σ2(Fo2) + (0.0496P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.03 | (Δ/σ)max < 0.001 |
3252 reflections | Δρmax = 0.16 e Å−3 |
184 parameters | Δρmin = −0.22 e Å−3 |
1 restraint | Absolute structure: Flack (1983), 1451 Friedel pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: −0.08 (8) |
C13H15NO5S | V = 1386.11 (13) Å3 |
Mr = 297.32 | Z = 4 |
Orthorhombic, Pca21 | Mo Kα radiation |
a = 12.4398 (6) Å | µ = 0.25 mm−1 |
b = 8.7538 (5) Å | T = 296 K |
c = 12.7288 (7) Å | 0.39 × 0.36 × 0.11 mm |
Bruker APEXII CCD area-detector diffractometer | 3252 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2540 reflections with I > 2σ(I) |
Tmin = 0.908, Tmax = 0.973 | Rint = 0.028 |
8843 measured reflections |
R[F2 > 2σ(F2)] = 0.036 | H-atom parameters constrained |
wR(F2) = 0.094 | Δρmax = 0.16 e Å−3 |
S = 1.03 | Δρmin = −0.22 e Å−3 |
3252 reflections | Absolute structure: Flack (1983), 1451 Friedel pairs |
184 parameters | Absolute structure parameter: −0.08 (8) |
1 restraint |
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 | ||
C1 | 0.58950 (17) | 0.7963 (3) | 0.8319 (2) | 0.0442 (5) | |
C2 | 0.66903 (18) | 0.8114 (3) | 0.7577 (2) | 0.0565 (6) | |
H2 | 0.7391 | 0.7816 | 0.7726 | 0.068* | |
C3 | 0.6434 (2) | 0.8714 (3) | 0.6609 (3) | 0.0703 (8) | |
H3 | 0.6967 | 0.8829 | 0.6103 | 0.084* | |
C4 | 0.5396 (2) | 0.9145 (3) | 0.6385 (2) | 0.0622 (7) | |
H4 | 0.5230 | 0.9536 | 0.5725 | 0.075* | |
C5 | 0.45981 (19) | 0.9001 (3) | 0.71319 (19) | 0.0509 (6) | |
H5 | 0.3900 | 0.9308 | 0.6976 | 0.061* | |
C6 | 0.48305 (15) | 0.8403 (3) | 0.81103 (17) | 0.0407 (5) | |
C7 | 0.39979 (15) | 0.8187 (3) | 0.89165 (18) | 0.0398 (5) | |
C8 | 0.40966 (15) | 0.7206 (2) | 0.97246 (19) | 0.0389 (5) | |
C9 | 0.32273 (17) | 0.7043 (3) | 1.04807 (18) | 0.0443 (5) | |
C10 | 0.2568 (3) | 0.5866 (3) | 1.2006 (3) | 0.0755 (8) | |
H10A | 0.1955 | 0.5455 | 1.1645 | 0.113* | |
H10B | 0.2378 | 0.6825 | 1.2322 | 0.113* | |
H10C | 0.2794 | 0.5165 | 1.2542 | 0.113* | |
C11 | 0.50112 (17) | 0.4660 (3) | 0.9658 (2) | 0.0493 (5) | |
H11A | 0.4465 | 0.4214 | 1.0107 | 0.059* | |
H11B | 0.5695 | 0.4204 | 0.9848 | 0.059* | |
C12 | 0.4761 (2) | 0.4257 (3) | 0.8530 (2) | 0.0589 (7) | |
H12A | 0.5279 | 0.4748 | 0.8072 | 0.071* | |
H12B | 0.4052 | 0.4639 | 0.8350 | 0.071* | |
C13 | 0.4794 (3) | 0.2548 (3) | 0.8355 (3) | 0.0812 (10) | |
H13A | 0.4297 | 0.2057 | 0.8823 | 0.122* | |
H13B | 0.5507 | 0.2178 | 0.8490 | 0.122* | |
H13C | 0.4600 | 0.2325 | 0.7641 | 0.122* | |
N1 | 0.50637 (13) | 0.6325 (2) | 0.98684 (13) | 0.0423 (5) | |
O1 | 0.70303 (11) | 0.6188 (2) | 0.95391 (16) | 0.0633 (5) | |
O2 | 0.62415 (13) | 0.8534 (2) | 1.02728 (17) | 0.0676 (6) | |
O3 | 0.31275 (12) | 0.90699 (18) | 0.87688 (13) | 0.0532 (4) | |
H3A | 0.2671 | 0.8861 | 0.9211 | 0.080* | |
O4 | 0.23788 (13) | 0.7728 (2) | 1.03972 (15) | 0.0586 (5) | |
O5 | 0.34308 (13) | 0.60963 (19) | 1.12699 (13) | 0.0547 (4) | |
S1 | 0.61649 (4) | 0.72551 (7) | 0.95848 (6) | 0.04848 (16) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0361 (10) | 0.0384 (12) | 0.0580 (13) | −0.0019 (9) | 0.0015 (10) | −0.0081 (10) |
C2 | 0.0407 (13) | 0.0523 (15) | 0.0765 (17) | −0.0002 (11) | 0.0107 (12) | −0.0006 (13) |
C3 | 0.0666 (18) | 0.0632 (18) | 0.081 (2) | 0.0040 (15) | 0.0342 (15) | 0.0044 (15) |
C4 | 0.0709 (17) | 0.0561 (17) | 0.0595 (16) | 0.0069 (13) | 0.0155 (14) | 0.0104 (13) |
C5 | 0.0502 (13) | 0.0437 (14) | 0.0587 (15) | 0.0032 (10) | 0.0017 (11) | 0.0047 (11) |
C6 | 0.0369 (10) | 0.0354 (12) | 0.0499 (13) | −0.0005 (9) | 0.0016 (9) | −0.0056 (10) |
C7 | 0.0322 (10) | 0.0402 (12) | 0.0471 (12) | 0.0021 (8) | −0.0027 (9) | −0.0072 (9) |
C8 | 0.0315 (8) | 0.0412 (11) | 0.0439 (14) | 0.0042 (8) | −0.0029 (9) | −0.0057 (10) |
C9 | 0.0403 (12) | 0.0447 (12) | 0.0480 (12) | 0.0016 (10) | 0.0004 (10) | −0.0040 (11) |
C10 | 0.0678 (16) | 0.095 (2) | 0.0642 (17) | 0.0176 (16) | 0.0203 (13) | 0.0219 (18) |
C11 | 0.0443 (10) | 0.0444 (12) | 0.0592 (13) | 0.0112 (9) | −0.0031 (11) | 0.0016 (13) |
C12 | 0.0590 (14) | 0.0499 (16) | 0.0677 (17) | −0.0024 (11) | −0.0011 (13) | −0.0091 (12) |
C13 | 0.077 (2) | 0.059 (2) | 0.107 (3) | −0.0003 (14) | 0.0020 (18) | −0.0210 (19) |
N1 | 0.0350 (9) | 0.0465 (11) | 0.0455 (12) | 0.0077 (7) | −0.0061 (7) | −0.0044 (8) |
O1 | 0.0354 (7) | 0.0806 (12) | 0.0740 (11) | 0.0161 (7) | −0.0059 (9) | −0.0045 (11) |
O2 | 0.0468 (10) | 0.0802 (14) | 0.0760 (12) | −0.0004 (8) | −0.0149 (8) | −0.0329 (11) |
O3 | 0.0378 (8) | 0.0548 (10) | 0.0669 (11) | 0.0137 (7) | 0.0065 (7) | 0.0114 (8) |
O4 | 0.0413 (9) | 0.0678 (11) | 0.0669 (11) | 0.0144 (8) | 0.0100 (8) | 0.0109 (9) |
O5 | 0.0484 (9) | 0.0677 (11) | 0.0480 (9) | 0.0105 (8) | 0.0071 (7) | 0.0092 (8) |
S1 | 0.0309 (2) | 0.0583 (3) | 0.0562 (3) | 0.0046 (2) | −0.0086 (3) | −0.0146 (3) |
C1—C2 | 1.374 (3) | C10—O5 | 1.439 (3) |
C1—C6 | 1.404 (3) | C10—H10A | 0.9600 |
C1—S1 | 1.759 (3) | C10—H10B | 0.9600 |
C2—C3 | 1.376 (4) | C10—H10C | 0.9600 |
C2—H2 | 0.9300 | C11—N1 | 1.483 (3) |
C3—C4 | 1.375 (4) | C11—C12 | 1.511 (4) |
C3—H3 | 0.9300 | C11—H11A | 0.9700 |
C4—C5 | 1.380 (3) | C11—H11B | 0.9700 |
C4—H4 | 0.9300 | C12—C13 | 1.513 (4) |
C5—C6 | 1.382 (3) | C12—H12A | 0.9700 |
C5—H5 | 0.9300 | C12—H12B | 0.9700 |
C6—C7 | 1.470 (3) | C13—H13A | 0.9600 |
C7—O3 | 1.344 (2) | C13—H13B | 0.9600 |
C7—C8 | 1.346 (3) | C13—H13C | 0.9600 |
C8—N1 | 1.441 (3) | N1—S1 | 1.6339 (19) |
C8—C9 | 1.455 (3) | O1—S1 | 1.4268 (15) |
C9—O4 | 1.219 (3) | O2—S1 | 1.425 (2) |
C9—O5 | 1.327 (3) | O3—H3A | 0.8200 |
C2—C1—C6 | 121.5 (2) | H10A—C10—H10C | 109.5 |
C2—C1—S1 | 121.76 (19) | H10B—C10—H10C | 109.5 |
C6—C1—S1 | 116.72 (17) | N1—C11—C12 | 114.2 (2) |
C1—C2—C3 | 119.0 (2) | N1—C11—H11A | 108.7 |
C1—C2—H2 | 120.5 | C12—C11—H11A | 108.7 |
C3—C2—H2 | 120.5 | N1—C11—H11B | 108.7 |
C4—C3—C2 | 120.5 (2) | C12—C11—H11B | 108.7 |
C4—C3—H3 | 119.7 | H11A—C11—H11B | 107.6 |
C2—C3—H3 | 119.7 | C11—C12—C13 | 111.4 (2) |
C3—C4—C5 | 120.5 (3) | C11—C12—H12A | 109.3 |
C3—C4—H4 | 119.8 | C13—C12—H12A | 109.3 |
C5—C4—H4 | 119.8 | C11—C12—H12B | 109.3 |
C4—C5—C6 | 120.4 (2) | C13—C12—H12B | 109.3 |
C4—C5—H5 | 119.8 | H12A—C12—H12B | 108.0 |
C6—C5—H5 | 119.8 | C12—C13—H13A | 109.5 |
C5—C6—C1 | 118.1 (2) | C12—C13—H13B | 109.5 |
C5—C6—C7 | 122.04 (19) | H13A—C13—H13B | 109.5 |
C1—C6—C7 | 119.8 (2) | C12—C13—H13C | 109.5 |
O3—C7—C8 | 123.2 (2) | H13A—C13—H13C | 109.5 |
O3—C7—C6 | 113.3 (2) | H13B—C13—H13C | 109.5 |
C8—C7—C6 | 123.46 (18) | C8—N1—C11 | 117.79 (16) |
C7—C8—N1 | 120.99 (19) | C8—N1—S1 | 113.92 (15) |
C7—C8—C9 | 120.03 (18) | C11—N1—S1 | 119.13 (14) |
N1—C8—C9 | 118.98 (19) | C7—O3—H3A | 109.5 |
O4—C9—O5 | 122.6 (2) | C9—O5—C10 | 115.99 (19) |
O4—C9—C8 | 122.6 (2) | O2—S1—O1 | 119.30 (11) |
O5—C9—C8 | 114.85 (18) | O2—S1—N1 | 108.17 (11) |
O5—C10—H10A | 109.5 | O1—S1—N1 | 108.37 (10) |
O5—C10—H10B | 109.5 | O2—S1—C1 | 107.40 (13) |
H10A—C10—H10B | 109.5 | O1—S1—C1 | 109.72 (11) |
O5—C10—H10C | 109.5 | N1—S1—C1 | 102.59 (9) |
C6—C1—C2—C3 | 0.1 (4) | N1—C8—C9—O5 | 1.8 (3) |
S1—C1—C2—C3 | −178.3 (2) | N1—C11—C12—C13 | 176.1 (2) |
C1—C2—C3—C4 | −0.5 (4) | C7—C8—N1—C11 | −108.9 (2) |
C2—C3—C4—C5 | 0.9 (4) | C9—C8—N1—C11 | 72.3 (3) |
C3—C4—C5—C6 | −0.9 (4) | C7—C8—N1—S1 | 37.8 (3) |
C4—C5—C6—C1 | 0.5 (3) | C9—C8—N1—S1 | −141.04 (17) |
C4—C5—C6—C7 | −178.1 (2) | C12—C11—N1—C8 | 63.6 (3) |
C2—C1—C6—C5 | −0.1 (3) | C12—C11—N1—S1 | −81.3 (2) |
S1—C1—C6—C5 | 178.34 (18) | O4—C9—O5—C10 | 2.7 (3) |
C2—C1—C6—C7 | 178.5 (2) | C8—C9—O5—C10 | −177.5 (2) |
S1—C1—C6—C7 | −3.0 (3) | C8—N1—S1—O2 | 61.60 (18) |
C5—C6—C7—O3 | −21.8 (3) | C11—N1—S1—O2 | −152.19 (18) |
C1—C6—C7—O3 | 159.7 (2) | C8—N1—S1—O1 | −167.73 (15) |
C5—C6—C7—C8 | 158.4 (2) | C11—N1—S1—O1 | −21.5 (2) |
C1—C6—C7—C8 | −20.2 (3) | C8—N1—S1—C1 | −51.72 (16) |
O3—C7—C8—N1 | −177.71 (19) | C11—N1—S1—C1 | 94.49 (18) |
C6—C7—C8—N1 | 2.1 (3) | C2—C1—S1—O2 | 100.0 (2) |
O3—C7—C8—C9 | 1.1 (3) | C6—C1—S1—O2 | −78.46 (19) |
C6—C7—C8—C9 | −179.1 (2) | C2—C1—S1—O1 | −31.1 (2) |
C7—C8—C9—O4 | 2.6 (3) | C6—C1—S1—O1 | 150.46 (17) |
N1—C8—C9—O4 | −178.5 (2) | C2—C1—S1—N1 | −146.1 (2) |
C7—C8—C9—O5 | −177.1 (2) | C6—C1—S1—N1 | 35.43 (19) |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3A···O4 | 0.82 | 1.84 | 2.558 (2) | 145 |
C3—H3···O2i | 0.93 | 2.48 | 3.358 (3) | 158 |
Symmetry code: (i) −x+3/2, y, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C13H15NO5S |
Mr | 297.32 |
Crystal system, space group | Orthorhombic, Pca21 |
Temperature (K) | 296 |
a, b, c (Å) | 12.4398 (6), 8.7538 (5), 12.7288 (7) |
V (Å3) | 1386.11 (13) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.25 |
Crystal size (mm) | 0.39 × 0.36 × 0.11 |
Data collection | |
Diffractometer | Bruker APEXII CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.908, 0.973 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8843, 3252, 2540 |
Rint | 0.028 |
(sin θ/λ)max (Å−1) | 0.667 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.036, 0.094, 1.03 |
No. of reflections | 3252 |
No. of parameters | 184 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.16, −0.22 |
Absolute structure | Flack (1983), 1451 Friedel pairs |
Absolute structure parameter | −0.08 (8) |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and Mercury (Macrae et al., 2006), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3A···O4 | 0.82 | 1.84 | 2.558 (2) | 145 |
C3—H3···O2i | 0.93 | 2.48 | 3.358 (3) | 158 |
Symmetry code: (i) −x+3/2, y, z−1/2. |
Acknowledgements
The authors are grateful to the Higher Education Commission of Pakistan and PCSIR Laboratories Complex for the provision of the diffractometer and chemicals, respectively.
References
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Benzothiazine1,1-dioxides are known to possess a versatile range of biological activities and have been synthesized continuously since the very first synthesis in 1923 (Braun, 1923). Among these, Piroxicam (Lombardino et al., 1971; Zia-ur-Rehman et al., 2005), and Meloxicam (Turck et al., 1996) are familiar for their analgesic and anti-inflammatory activities and are being used world wide as non-steroidal anti-inflammatory drugs (NSAIDs). Few of its derivatives are also known as potent calpain I inhibitors (Bihovsky et al., 2004), while benzothiaine-3-yl-quinazolin-4-ones showed marked activity against Bacillus subtilis (Zia-ur-Rehman et al., 2006). As part of a research program synthesizing various bioactive benzothiazines (Zia-ur-Rehman et al., 2005, 2006, 2009), we herein report the crystal structure of the title compound, (I).
In the molecule of the title compound (Fig. 1), the thiazine ring exhibits a distorted half-chair conformation with S1/C1/C6/C7 atoms lying in a plane and N1 showing significant departure from the plane due to its pyramidal geometry projecting the propyl group approximately perpendicular to the ring. Like other 1,2-benzothiazine 1,1-dioxide derivatives (Fabiola et al., 1998; Zia-ur-Rehman et al., 2007), the enolic hydrogen on O3 is involved in intramolecular hydrogen bonding (Table1). Also, C7—C8 bond length [1.346 (3) Å] (very close to normal C—C bond 1.36 Å) indicates a partial double-bond character indicating the dominance of enolic form in the molecule. The C1—S1 bond distance [1.759 (3) Å] is as expected for typical C(sp2)—S bond (1.751 Å). Each molecule is linked to neighbouring molecules via weaker C—H···O=S interactions giving rise to zigzag chains along the c axis (Fig. 2).