Methyl 2-benzyl-4-hy­droxy-1,1-dioxo-1,2,3,4-tetra­hydro-1λ6,2-benzothia­zine-3-carboxyl­ate

Muhammad Nadeem Arshad; Islam Ullah Khan; Muhammad Zia-ur-Rehman; Muhammad Shafiq; Abdullah M Asiri

doi:10.1107/S1600536811020289

. 2011 Jun 4;67(Pt 7):o1588–o1589. doi: 10.1107/S1600536811020289

Methyl 2-benzyl-4-hydroxy-1,1-dioxo-1,2,3,4-tetrahydro-1λ⁶,2-benzothiazine-3-carboxylate

Muhammad Nadeem Arshad ^a,^*,^‡, Islam Ullah Khan ^b, Muhammad Zia-ur-Rehman ^c, Muhammad Shafiq ^b, Abdullah M Asiri ^d

PMCID: PMC3151898 PMID: 21836997

Abstract

In the title compound, C₁₇H₁₅NO₅S, the benzene ring of the fused-ring system is twisted by 11.67 (6)° with respect to the thiazine ring. The atoms of the four-atom methyl ester group and the phenyl ring of the benzyl unit are inclined at 16.50 (7) and 44.52 (3)° with respect to the thiazine ring. An intramolecular O—H⋯O hydrogen bond gives rise to a six-membered S(6) ring motif. In the crystal, molecules are extended through a C—H⋯O interaction along the a axis. C—H⋯π interactions are also observed.

Related literature

For the biological properties of benzothiazines, see: Zia-ur-Rehman et al. (2005 ▶, 2006 ▶). For a related structure, see: Arshad et al. (2009 ▶). For graph-set notation, see: Bernstein et al. (1995 ▶).

Experimental

Crystal data

C₁₇H₁₅NO₅S
M _r = 345.36
Monoclinic,
a = 9.4920 (15) Å
b = 10.9607 (17) Å
c = 15.050 (2) Å
β = 99.758 (2)°
V = 1543.1 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.24 mm⁻¹
T = 173 K
0.43 × 0.25 × 0.19 mm

Data collection

Bruker SMART 1K diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ▶) T _min = 0.905, T _max = 0.956
13430 measured reflections
3719 independent reflections
3297 reflections with I > 2σ(I)
R _int = 0.033

Refinement

R[F ² > 2σ(F ²)] = 0.042
wR(F ²) = 0.119
S = 1.06
3719 reflections
221 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.79 e Å⁻³
Δρ_min = −0.57 e Å⁻³

Data collection: SMART (Bruker, 2001 ▶); cell refinement: SAINT (Bruker, 2001 ▶); 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, 1997 ▶) and PLATON (Spek, 2009 ▶); software used to prepare material for publication: X-SEED (Barbour, 2001) ▶, WinGX (Farrugia, 1999 ▶) and PLATON.

Supplementary Material

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536811020289/ng5172sup1.cif

e-67-o1588-sup1.cif^{(19.8KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811020289/ng5172Isup2.hkl

e-67-o1588-Isup2.hkl^{(178.6KB, hkl)}

Supplementary material file. DOI: 10.1107/S1600536811020289/ng5172Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

Cg1 is the centroid of the C1–C6 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O4ⁱ	0.95	2.49	3.1861 (19)	130
O1—H1O⋯O4	0.93 (2)	1.72 (2)	2.5580 (15)	149 (2)
C10—H10B⋯Cg1ⁱⁱ	0.80	2.94	3.6391 (18)	130

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Symmetry codes: (i) Inline graphic ; (ii) .

Acknowledgments

MNA acknowledges the HEC for providing a Fellowship under the International Research Support Initiative Program (IRSIP)

supplementary crystallographic information

Comment

Crystallographic and biological studies of benzothiazine molecules and their derivatives gained much attraction in recent literature (Zia-ur-Rehman et al. 2005, 2006) and (Arshad et al. 2009).

The title compound is N-alkylated derivative of methyl -4-hydroxy-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide. The methyl ester moiety attached to the thiazine ring is almost planer showing the r. m. s. deviation of 0.0087Å and is oriented at dihedral angle of 16.50 (7)° with respect to the thiazine ring. The typical intramolecular O–H···O interaction of 4-hydroxy benzothiazine molecules observed and generates almost planer six membered ring motif S₁¹(6)(Bernstein, et al., 1995) with the r.m.s deviaton of 0.0085Å and produces dihedral angles of 16.02 (33)° & 15.87 (32)° with respect to the thiazine and aromatic (C1/C2/C3/C4/C5/C6) rings respectively. The thiazine ring adopted the half chair shaped as the S1 and N1 showed maximum deviation from the least square plane measure 0.3113 (7)Å and 0.3082 (8)Å respectively and root mean square deviation for the ring is 0.2031Å. A weak intermolecular hydrogen bonding interaction observed along the a axes (Fig.2. Tab.1). Further hydrogen atom from methyl group of ester moiety involved in symmetry related C—H···.π interaction [C10—H10B···.Cg1, where Cg1 is centroid of (C1—C6)] table 1. The benzyl ring attached to nitogen atom of thiazine ring is oriented at dihedral angle of 51.33 (3)° and 44.52 (3)° with respect to the aromatic (C1—C6) and thiazine rings respectively.

Experimental

A mixture of methyl 4-hydroxy-2H-1,2-benzothiazine-3-carboxylate-1,1-dioxide (350 mg, 1.37 mmol), sodium hydride (77 mg, 3.2 mmol) and dimethylformamide (5 ml) was prperaed in a round bottom flask. Benzyl Chloride (202 mg, 1.6 mmol) was added drop wise to the above mixture. Contents were allowed to stirr at room temperature for 5 h under nitrogen atmosphere and poured over ice cooled water (100 ml). The pH was adjusted 2-3 using 1N HCL which yielded precipetates . The precipitates were filtered, washed with cold water and dried. Single crystals were obtained by re-crystallization from a methanol solution under slow evaporation.