organic compounds
Ethyl 2-{5-[(3-oxo-3,4-dihydro-2H-1,4-benzothiazin-4-yl)methyl]-1H-1,2,3-triazol-1-yl}acetate
aLaboratoire de Chimie Organique Hétérocyclique URAC 21, Pharmacochimie, Av Ibn Battouta, BP 1014, Faculté des Sciences, Université Mohammed V-Agdal, Rabat, Morocco, bLaboratoire de Chimie Organique et Etudes Physico-chimique, ENS Takaddoum, Rabat, Morocco, and cLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Battouta, BP 1014, Rabat, Morocco
*Correspondence e-mail: nk_sebbar@yahoo.fr
In the title compound, C15H16N4O3S, the six-membered heterocycle of the benzothiazine fragment exhibits a screw boat conformation. The dihedral angle between the planes through the triazole ring and the benzene ring fused to the 1,4-thiazine ring is 62.98 (11)°. The mean plane formed by the atoms belonging to the acetate group is nearly perpendicular to the triazole ring [dihedral angle = 74.65 (12)°]. In the crystal, molecules are linked by pairs of C—H⋯O interactions, forming dimeric aggregates.
CCDC reference: 978857
Related literature
For the pharmacological activity of benzothiazine derivatives, see: Fringuelli et al. (1998); Lopatina et al. (1982); Rathore & Kumar (2006). For related structures, see: Keita et al. (2000); Zerzouf et al. (2001); Barryala et al. (2011). For puckering calculation see: Cremer & Pople (1975).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; 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, 2012); software used to prepare material for publication: PLATON (Spek, 2009) and publCIF (Westrip, 2010).
Supporting information
CCDC reference: 978857
10.1107/S1600536813034697/tk5283sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536813034697/tk5283Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536813034697/tk5283Isup3.cml
To a solution of 4-(prop-2-yn-1-yl)-2H-1, 4-benzothiazin-3-one (0.2 g, 0.7 mmol) in ethanol (15 ml) was added azide ethyl acetate (0.20 ml, 1.89 mmol). The mixture was stirred under reflux for 24 h. After completion of reaction (monitored by TLC), the solution was concentrated and the residue was purified by
on silica gel by using a mixture (hexane/ethyl acetate 2/1). Crystals were obtained when the solvent was allowed to evaporate. The solid product was purified by recrystallization from ethanol to afford yellow crystals in 75% yield.The H atoms were located in a difference map and treated as riding with C—H = 0.93 Å (aromatic), C—H = 0.97 Å (methylene) and C—H = 0.96 Å, (methyl), and with Uiso(H) = 1.2 Ueq (methylene and ammonium) and Uiso(H) = 1.5 Ueq for the methyl. Owing to poor aggreement, three reflections, i.e. (0 1 1), (0 1 0) and (0 0 1), were omitted from the final cycles of refinement.
Several derivatives of benzothiazines form an important class of bioactive molecules in the field of drugs and pharmaceuticals. Applications in various therapeutic areas, include their use as anti-depressants (Lopatina et al., 1982); anti-fungals (Fringuelli et al., 1998) and anti-microbials (Rathore & Kumar, 2006). The present work is a continuation of the investigation of the benzothiazine derivatives published recently by our team (Keita et al., 2000; Zerzouf et al., 2001; Barryala et al., 2011). The aim of the present paper was to study the recently synthesized ethyl2-{5-[(3-oxo-2H-1,4-benzothiazin-4-yl)methyl]- 1,2,3-triazol-1-yl}acetate
by X-ray crystallography at room temperature.The molecule of the title compound is build up from two fused six-membered rings linked to a triazole ring which is attached to an ethylacetate group as shown in Fig.1. The 1,4-thiazine ring adopts a screw boat conformation as indicated by the puckering amplitude Q = 0.6536 (17) Å, and spherical polar angle θ = 112.04 (16)°, with φ = 152.14 (18)° (Cremer & Pople, 1975). The benzene ring (C1 to C6) makes a dihedral angle of 62.98 (11)° with the triazole ring (N2N3N4C10C11) which is nearly perpendicular to the mean plane through the acetate atoms (C12C13O2O3) as indicated by the dihedral angle between them of 74.65 (12)°. In the crystal, the molecules are linked by weak intermolecular C4–H4···O2 interactions to form dimers (see Fig.2 and Table 1).
Several derivatives of benzothiazines form an important class of bioactive molecules in the field of drugs and pharmaceuticals. Applications in various therapeutic areas, include their use as anti-depressants (Lopatina et al., 1982); anti-fungals (Fringuelli et al., 1998) and anti-microbials (Rathore & Kumar, 2006). The present work is a continuation of the investigation of the benzothiazine derivatives published recently by our team (Keita et al., 2000; Zerzouf et al., 2001; Barryala et al., 2011). The aim of the present paper was to study the recently synthesized ethyl2-{5-[(3-oxo-2H-1,4-benzothiazin-4-yl)methyl]- 1,2,3-triazol-1-yl}acetate
by X-ray crystallography at room temperature.The molecule of the title compound is build up from two fused six-membered rings linked to a triazole ring which is attached to an ethylacetate group as shown in Fig.1. The 1,4-thiazine ring adopts a screw boat conformation as indicated by the puckering amplitude Q = 0.6536 (17) Å, and spherical polar angle θ = 112.04 (16)°, with φ = 152.14 (18)° (Cremer & Pople, 1975). The benzene ring (C1 to C6) makes a dihedral angle of 62.98 (11)° with the triazole ring (N2N3N4C10C11) which is nearly perpendicular to the mean plane through the acetate atoms (C12C13O2O3) as indicated by the dihedral angle between them of 74.65 (12)°. In the crystal, the molecules are linked by weak intermolecular C4–H4···O2 interactions to form dimers (see Fig.2 and Table 1).
For the pharmacological activity of benzothiazine derivatives, see: Fringuelli et al. (1998); Lopatina et al. (1982); Rathore & Kumar (2006). For related structures, see: Keita et al. (2000); Zerzouf et al. (2001); Barryala et al. (2011). For puckering calculation see: Cremer & Pople (1975).
To a solution of 4-(prop-2-yn-1-yl)-2H-1, 4-benzothiazin-3-one (0.2 g, 0.7 mmol) in ethanol (15 ml) was added azide ethyl acetate (0.20 ml, 1.89 mmol). The mixture was stirred under reflux for 24 h. After completion of reaction (monitored by TLC), the solution was concentrated and the residue was purified by
on silica gel by using a mixture (hexane/ethyl acetate 2/1). Crystals were obtained when the solvent was allowed to evaporate. The solid product was purified by recrystallization from ethanol to afford yellow crystals in 75% yield. detailsThe H atoms were located in a difference map and treated as riding with C—H = 0.93 Å (aromatic), C—H = 0.97 Å (methylene) and C—H = 0.96 Å, (methyl), and with Uiso(H) = 1.2 Ueq (methylene and ammonium) and Uiso(H) = 1.5 Ueq for the methyl. Owing to poor aggreement, three reflections, i.e. (0 1 1), (0 1 0) and (0 0 1), were omitted from the final cycles of refinement.
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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, 2012); software used to prepare material for publication: PLATON (Spek, 2009) and publCIF (Westrip, 2010).C15H16N4O3S | Z = 2 |
Mr = 332.38 | F(000) = 348 |
Triclinic, P1 | Dx = 1.367 Mg m−3 |
a = 5.6414 (2) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 11.1604 (4) Å | Cell parameters from 3560 reflections |
c = 13.3724 (5) Å | θ = 2.8–27.1° |
α = 73.823 (2)° | µ = 0.22 mm−1 |
β = 87.226 (2)° | T = 296 K |
γ = 88.566 (2)° | Block, yellow |
V = 807.59 (5) Å3 | 0.37 × 0.34 × 0.28 mm |
Bruker X8 APEX diffractometer | 3560 independent reflections |
Radiation source: fine-focus sealed tube | 2963 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.028 |
φ and ω scans | θmax = 27.1°, θmin = 2.8° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −7→7 |
Tmin = 0.692, Tmax = 0.747 | k = −14→14 |
16305 measured reflections | l = −17→16 |
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)] = 0.045 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.124 | H-atom parameters constrained |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0523P)2 + 0.3602P] where P = (Fo2 + 2Fc2)/3 |
3560 reflections | (Δ/σ)max < 0.001 |
208 parameters | Δρmax = 0.39 e Å−3 |
0 restraints | Δρmin = −0.32 e Å−3 |
C15H16N4O3S | γ = 88.566 (2)° |
Mr = 332.38 | V = 807.59 (5) Å3 |
Triclinic, P1 | Z = 2 |
a = 5.6414 (2) Å | Mo Kα radiation |
b = 11.1604 (4) Å | µ = 0.22 mm−1 |
c = 13.3724 (5) Å | T = 296 K |
α = 73.823 (2)° | 0.37 × 0.34 × 0.28 mm |
β = 87.226 (2)° |
Bruker X8 APEX diffractometer | 3560 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 2963 reflections with I > 2σ(I) |
Tmin = 0.692, Tmax = 0.747 | Rint = 0.028 |
16305 measured reflections |
R[F2 > 2σ(F2)] = 0.045 | 0 restraints |
wR(F2) = 0.124 | H-atom parameters constrained |
S = 1.05 | Δρmax = 0.39 e Å−3 |
3560 reflections | Δρmin = −0.32 e Å−3 |
208 parameters |
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 > 2σ(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 | 0.0414 (3) | 0.32734 (16) | 0.35494 (13) | 0.0404 (4) | |
C2 | −0.1005 (4) | 0.43140 (19) | 0.35277 (16) | 0.0584 (5) | |
H2 | −0.1086 | 0.4960 | 0.2916 | 0.070* | |
C3 | −0.2296 (5) | 0.4392 (3) | 0.4410 (2) | 0.0816 (8) | |
H3 | −0.3226 | 0.5097 | 0.4391 | 0.098* | |
C4 | −0.2224 (5) | 0.3437 (3) | 0.5320 (2) | 0.0848 (8) | |
H4 | −0.3130 | 0.3488 | 0.5907 | 0.102* | |
C5 | −0.0814 (4) | 0.2415 (3) | 0.53555 (16) | 0.0681 (6) | |
H5 | −0.0755 | 0.1775 | 0.5972 | 0.082* | |
C6 | 0.0537 (3) | 0.23176 (18) | 0.44807 (14) | 0.0469 (4) | |
C7 | 0.4681 (3) | 0.1852 (2) | 0.36729 (17) | 0.0589 (5) | |
H7A | 0.5360 | 0.2444 | 0.3986 | 0.071* | |
H7B | 0.5927 | 0.1272 | 0.3581 | 0.071* | |
C8 | 0.3767 (3) | 0.25404 (16) | 0.26244 (15) | 0.0435 (4) | |
C9 | 0.0720 (3) | 0.38039 (16) | 0.16053 (13) | 0.0386 (4) | |
H9A | −0.0999 | 0.3767 | 0.1659 | 0.046* | |
H9B | 0.1268 | 0.3362 | 0.1106 | 0.046* | |
C10 | 0.1439 (3) | 0.51384 (15) | 0.12016 (12) | 0.0351 (3) | |
C11 | 0.3619 (3) | 0.56739 (15) | 0.10351 (14) | 0.0399 (4) | |
H11 | 0.5090 | 0.5274 | 0.1139 | 0.048* | |
C12 | 0.4837 (3) | 0.79233 (16) | 0.04712 (13) | 0.0422 (4) | |
H12A | 0.4078 | 0.8677 | 0.0059 | 0.051* | |
H12B | 0.6199 | 0.7737 | 0.0066 | 0.051* | |
C13 | 0.5656 (4) | 0.81404 (19) | 0.14565 (15) | 0.0498 (4) | |
C14 | 0.8094 (7) | 0.9430 (4) | 0.2083 (2) | 0.1208 (14) | |
H14A | 0.6953 | 0.9796 | 0.2482 | 0.145* | |
H14B | 0.8669 | 0.8653 | 0.2541 | 0.145* | |
C15 | 0.9975 (6) | 1.0233 (3) | 0.1746 (3) | 0.1089 (12) | |
H15A | 1.0693 | 1.0380 | 0.2337 | 0.163* | |
H15B | 0.9412 | 1.1010 | 0.1303 | 0.163* | |
H15C | 1.1128 | 0.9867 | 0.1364 | 0.163* | |
N1 | 0.1656 (2) | 0.31606 (12) | 0.26288 (10) | 0.0359 (3) | |
N2 | −0.0215 (3) | 0.60571 (14) | 0.09455 (13) | 0.0471 (4) | |
N3 | 0.0854 (3) | 0.71393 (14) | 0.06368 (13) | 0.0486 (4) | |
N4 | 0.3184 (2) | 0.69022 (13) | 0.06899 (11) | 0.0380 (3) | |
O1 | 0.4877 (3) | 0.25525 (15) | 0.18177 (12) | 0.0619 (4) | |
O2 | 0.5302 (4) | 0.7457 (2) | 0.23075 (13) | 0.1013 (8) | |
O3 | 0.6924 (3) | 0.91691 (13) | 0.12300 (11) | 0.0560 (4) | |
S1 | 0.23551 (10) | 0.10089 (5) | 0.45316 (4) | 0.06117 (19) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0407 (9) | 0.0437 (9) | 0.0341 (8) | −0.0073 (7) | 0.0014 (7) | −0.0060 (7) |
C2 | 0.0686 (13) | 0.0517 (11) | 0.0476 (11) | 0.0061 (10) | 0.0149 (10) | −0.0052 (9) |
C3 | 0.097 (2) | 0.0739 (16) | 0.0688 (16) | 0.0123 (14) | 0.0299 (14) | −0.0176 (13) |
C4 | 0.098 (2) | 0.104 (2) | 0.0478 (13) | 0.0025 (17) | 0.0262 (13) | −0.0187 (13) |
C5 | 0.0732 (15) | 0.0872 (17) | 0.0330 (10) | −0.0082 (13) | 0.0021 (10) | 0.0015 (10) |
C6 | 0.0438 (9) | 0.0539 (10) | 0.0369 (9) | −0.0068 (8) | −0.0049 (7) | −0.0015 (8) |
C7 | 0.0386 (10) | 0.0640 (13) | 0.0608 (13) | 0.0032 (9) | −0.0069 (9) | 0.0052 (10) |
C8 | 0.0369 (9) | 0.0409 (9) | 0.0481 (10) | −0.0043 (7) | −0.0002 (7) | −0.0046 (7) |
C9 | 0.0370 (8) | 0.0419 (9) | 0.0338 (8) | −0.0049 (7) | −0.0042 (6) | −0.0049 (7) |
C10 | 0.0326 (8) | 0.0403 (8) | 0.0291 (8) | 0.0007 (6) | −0.0027 (6) | −0.0039 (6) |
C11 | 0.0327 (8) | 0.0367 (8) | 0.0453 (9) | 0.0027 (6) | −0.0022 (7) | −0.0031 (7) |
C12 | 0.0479 (10) | 0.0376 (8) | 0.0360 (9) | −0.0069 (7) | −0.0020 (7) | −0.0014 (7) |
C13 | 0.0559 (11) | 0.0526 (11) | 0.0380 (10) | −0.0085 (9) | −0.0009 (8) | −0.0073 (8) |
C14 | 0.153 (3) | 0.155 (3) | 0.0655 (18) | −0.077 (3) | −0.0210 (19) | −0.039 (2) |
C15 | 0.117 (3) | 0.116 (3) | 0.096 (2) | −0.047 (2) | −0.038 (2) | −0.0240 (19) |
N1 | 0.0348 (7) | 0.0363 (7) | 0.0326 (7) | −0.0022 (5) | −0.0014 (5) | −0.0028 (5) |
N2 | 0.0332 (7) | 0.0468 (8) | 0.0536 (9) | 0.0020 (6) | −0.0060 (6) | −0.0009 (7) |
N3 | 0.0394 (8) | 0.0432 (8) | 0.0555 (10) | 0.0059 (6) | −0.0070 (7) | −0.0008 (7) |
N4 | 0.0358 (7) | 0.0362 (7) | 0.0368 (7) | −0.0004 (5) | −0.0022 (5) | −0.0018 (6) |
O1 | 0.0508 (8) | 0.0707 (10) | 0.0586 (9) | 0.0096 (7) | 0.0109 (7) | −0.0119 (7) |
O2 | 0.1505 (19) | 0.1102 (15) | 0.0355 (9) | −0.0617 (14) | −0.0002 (10) | −0.0028 (9) |
O3 | 0.0673 (9) | 0.0560 (8) | 0.0456 (8) | −0.0148 (7) | −0.0102 (6) | −0.0131 (6) |
S1 | 0.0544 (3) | 0.0533 (3) | 0.0578 (3) | −0.0006 (2) | −0.0062 (2) | 0.0150 (2) |
C1—C2 | 1.388 (3) | C9—H9B | 0.9700 |
C1—C6 | 1.399 (2) | C10—N2 | 1.351 (2) |
C1—N1 | 1.421 (2) | C10—C11 | 1.362 (2) |
C2—C3 | 1.379 (3) | C11—N4 | 1.339 (2) |
C2—H2 | 0.9300 | C11—H11 | 0.9300 |
C3—C4 | 1.378 (4) | C12—N4 | 1.448 (2) |
C3—H3 | 0.9300 | C12—C13 | 1.500 (3) |
C4—C5 | 1.365 (4) | C12—H12A | 0.9700 |
C4—H4 | 0.9300 | C12—H12B | 0.9700 |
C5—C6 | 1.394 (3) | C13—O2 | 1.191 (2) |
C5—H5 | 0.9300 | C13—O3 | 1.322 (2) |
C6—S1 | 1.751 (2) | C14—C15 | 1.381 (4) |
C7—C8 | 1.507 (3) | C14—O3 | 1.446 (3) |
C7—S1 | 1.800 (2) | C14—H14A | 0.9700 |
C7—H7A | 0.9700 | C14—H14B | 0.9700 |
C7—H7B | 0.9700 | C15—H15A | 0.9600 |
C8—O1 | 1.217 (2) | C15—H15B | 0.9600 |
C8—N1 | 1.363 (2) | C15—H15C | 0.9600 |
C9—N1 | 1.473 (2) | N2—N3 | 1.314 (2) |
C9—C10 | 1.495 (2) | N3—N4 | 1.335 (2) |
C9—H9A | 0.9700 | ||
C2—C1—C6 | 119.07 (17) | C11—C10—C9 | 131.21 (15) |
C2—C1—N1 | 120.41 (15) | N4—C11—C10 | 104.97 (14) |
C6—C1—N1 | 120.48 (17) | N4—C11—H11 | 127.5 |
C3—C2—C1 | 120.2 (2) | C10—C11—H11 | 127.5 |
C3—C2—H2 | 119.9 | N4—C12—C13 | 111.39 (14) |
C1—C2—H2 | 119.9 | N4—C12—H12A | 109.4 |
C4—C3—C2 | 120.8 (2) | C13—C12—H12A | 109.4 |
C4—C3—H3 | 119.6 | N4—C12—H12B | 109.4 |
C2—C3—H3 | 119.6 | C13—C12—H12B | 109.4 |
C5—C4—C3 | 119.6 (2) | H12A—C12—H12B | 108.0 |
C5—C4—H4 | 120.2 | O2—C13—O3 | 125.37 (19) |
C3—C4—H4 | 120.2 | O2—C13—C12 | 124.90 (19) |
C4—C5—C6 | 120.9 (2) | O3—C13—C12 | 109.65 (15) |
C4—C5—H5 | 119.5 | C15—C14—O3 | 112.4 (3) |
C6—C5—H5 | 119.5 | C15—C14—H14A | 109.1 |
C5—C6—C1 | 119.4 (2) | O3—C14—H14A | 109.1 |
C5—C6—S1 | 120.78 (16) | C15—C14—H14B | 109.1 |
C1—C6—S1 | 119.84 (15) | O3—C14—H14B | 109.1 |
C8—C7—S1 | 111.53 (13) | H14A—C14—H14B | 107.8 |
C8—C7—H7A | 109.3 | C14—C15—H15A | 109.5 |
S1—C7—H7A | 109.3 | C14—C15—H15B | 109.5 |
C8—C7—H7B | 109.3 | H15A—C15—H15B | 109.5 |
S1—C7—H7B | 109.3 | C14—C15—H15C | 109.5 |
H7A—C7—H7B | 108.0 | H15A—C15—H15C | 109.5 |
O1—C8—N1 | 121.92 (17) | H15B—C15—H15C | 109.5 |
O1—C8—C7 | 121.56 (17) | C8—N1—C1 | 123.85 (14) |
N1—C8—C7 | 116.51 (16) | C8—N1—C9 | 116.72 (14) |
N1—C9—C10 | 113.91 (13) | C1—N1—C9 | 119.33 (14) |
N1—C9—H9A | 108.8 | N3—N2—C10 | 109.05 (14) |
C10—C9—H9A | 108.8 | N2—N3—N4 | 106.88 (14) |
N1—C9—H9B | 108.8 | N3—N4—C11 | 111.00 (14) |
C10—C9—H9B | 108.8 | N3—N4—C12 | 119.89 (14) |
H9A—C9—H9B | 107.7 | C11—N4—C12 | 128.89 (14) |
N2—C10—C11 | 108.10 (14) | C13—O3—C14 | 116.59 (19) |
N2—C10—C9 | 120.68 (14) | C6—S1—C7 | 95.49 (10) |
D—H···A | D—H | H···A | D···A | D—H···A |
C4—H4···O2i | 0.93 | 2.59 | 3.445 (3) | 154 |
Symmetry code: (i) −x, −y+1, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
C4—H4···O2i | 0.93 | 2.59 | 3.445 (3) | 154 |
Symmetry code: (i) −x, −y+1, −z+1. |
Acknowledgements
The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.
References
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