Methyl 4-eth­oxy-2-methyl-2H-1,2-benzothia­zine-3-carboxyl­ate 1,1-dioxide

Zia-ur-Rehman, M.; Choudary, J.A.; Elsegood, M.R.J.; Akbar, N.; Latif Siddiqui, H.

doi:10.1107/S1600536808021363

organic compounds

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ISSN: 2056-9890

Volume 64| Part 8| August 2008| Page o1508

doi:10.1107/S1600536808021363

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Methyl 4-ethoxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide

Muhammad Zia-ur-Rehman,^a Jamil Anwar Choudary,^b Mark R. J. Elsegood,^c Noshin Akbar ^d ^* and Hamid Latif Siddiqui ^b

^aApplied Chemistry Research Centre, PCSIR Laboratories Complex, Lahore 54600, Pakistan, ^bInstitute of Chemistry, University of The Punjab, Lahore 54590, Pakistan, ^cChemistry Department, Loughborough University, Loughborough, Leicestershire LE11 3TU, England, and ^dDepartment of Chemistry, University of Science and Technology, Bannu, Pakistan
^*Correspondence e-mail: noshinakbar@yahoo.com

(Received 8 July 2008; accepted 9 July 2008; online 16 July 2008)

In the crystal structure of the title compound, C₁₃H₁₅NO₅S, the molecules exhibit weak S=O⋯H—C and C=O⋯H—C intermolecular interactions and arrange themselves into centrosymmetric dimers by means of π–π interactions (ring centroids are separated by 3.619 Å, while the closest C⋯C contacts are 3.514 Å). 1,2-Benzothiazines of this kind have a range of biological activities and are used as medicines in the treatment of inflammation and rheumatoid arthritis.

Related literature

For related literature on benzothiazines, see: Ahmad et al. (2008 ); Bihovsky et al. (2004 ); Fabiola et al. (1998 ); Golič et al. (1987 ); Kojić-Prodić & Rużić-Toroš (1982 ); Lombardino et al. (1971 ); Reck et al. (1988 ); Zia-ur-Rehman et al. (2005 , 2006 , 2007 ).

Experimental

Crystal data

C₁₃H₁₅NO₅S
M_r = 297.32
Triclinic, $[P \overline 1]$
a = 7.9810 (4) Å
b = 8.1215 (4) Å
c = 10.8173 (6) Å
α = 89.4783 (7)°
β = 79.5124 (8)°
γ = 79.3434 (7)°
V = 677.33 (6) Å³
Z = 2
Mo Kα radiation
μ = 0.26 mm⁻¹
T = 150 (2) K
0.57 × 0.17 × 0.10 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2007 ) T_min = 0.867, T_max = 0.975
8153 measured reflections
4069 independent reflections
3678 reflections with I > 2σ(I)
R_int = 0.014

Refinement

R[F² > 2σ(F²)] = 0.033
wR(F²) = 0.096
S = 1.07
4069 reflections
184 parameters
H-atom parameters constrained
Δρ_max = 0.47 e Å⁻³
Δρ_min = −0.34 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5⋯O2ⁱ	0.95	2.51	3.2726 (13)	137
C13—H13A⋯O5ⁱ	0.98	2.58	3.3715 (15)	138
Symmetry code: (i) x, y-1, z.

Data collection: APEX2 (Bruker, 2006 ); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and local programs.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808021363/bt2743sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808021363/bt2743Isup2.hkl

checkCIF report

Comment top

1,2-Benzothiazine 1,1-dioxides are heterocyclic compounds with numerous types of biological activity reported. For example, some are found useful as medicaments in the treatment of inflammation and rheumatoid arthritis (Lombardino et al., 1971). Other 1,2-benzothiazine 1,1-dioxides exhibit hyperlipidemic, anti-bacterial and Calpain I inhibition activities while they have also been found useful as endothelin receptor antagonists (Bihovsky et al., 2004). In continuation to our ongoing work on the synthesis of benzothiazine 1,1-dioxides (Zia-ur-Rehman et al., 2005, 2006, 2007; Ahmad et al., 2008), we herein report the synthesis and crystal structure of the title compound, (I).

In (I), the thiazine ring exhibits a distorted half-chair conformation with S1/C1/C6/C7 relatively planar (within +/- 0.0336 (6) Å) and N1 showing significant deviation from this plane due to its pyramidal geometry with the methyl group pointing approximately perpendicular to the plane. Compared with related molecules having no substitution at O3 [1.352 (9) Å; Golič et al., 1987; 1.339 (15) Å; Kojić-Prodić & Rużić-Toroš, 1982; 1.350 (9) Å; Reck et al., 1988; 1.336 (2) Å; Fabiola et al., 1998], C9—O4 in (I) is found to be shorter due to the absence of hydrogen bonding at O4. Each molecule of (I) is linked to its neighbours through inter-molecular C-H···S and C-H···O interactions giving rise to chains of molecules parallel to b (Fig. 2). Additionally, the molecules in are linked into centro-symmetric dimers by means of π-π interactions. The ring centroids are separated by 3.619 Å, while the closest C···C contacts are between C2 and C4'', separated by 3.514 Å (symmetry operator -x, -y, 1 - z).

Related literature top

For related literature on benzothiazines, see: Ahmad et al. (2008); Bihovsky et al. (2004); Fabiola et al. (1998); Golič et al. (1987); Kojić-Prodić & Rużić-Toroš (1982); Lombardino et al. (1971); Reck et al. (1988); Zia-ur-Rehman et al. (2005, 2006, 2007).

Experimental top

A mixture of methyl 4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide (1.33 g; 5.0 mmoles), ethyl iodide (3.90 g; 25.0 mmoles), anhydrous potassium carbonate (10.0 g) and acetonitrile (100 ml) was stirred and refluxed for a period of 7 h. After removal of acetonitrile and excess methyl iodide under vacuum, chloroform (30 ml) was added and the resultant mixture was filtered. The filtrate was washed with water to remove potassium carbonate, dried with anhydrous sodium sulfate and filtered. Slow evaporation of the solvent afforded the crystalline product. Yield:1.26 g; 77.8%; m.p.147°C.

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and local programs.

Figures top

	Fig. 1. The molecular structure of (I), with displacement ellipsoids at the 50% probability level.
	Fig. 2. Packing plot showing the two unique weak H-bonds (thin dashed lines) and π-π interactions (thick dashed lines).

Methyl 4-ethoxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide top

Crystal data top

C₁₃H₁₅NO₅S	Z = 2
M_r = 297.32	F(000) = 312
Triclinic, P1	D_x = 1.458 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.9810 (4) Å	Cell parameters from 4878 reflections
b = 8.1215 (4) Å	θ = 2.6–30.5°
c = 10.8173 (6) Å	µ = 0.26 mm⁻¹
α = 89.4783 (7)°	T = 150 K
β = 79.5124 (8)°	Block, colourless
γ = 79.3434 (7)°	0.57 × 0.17 × 0.10 mm
V = 677.33 (6) Å³

Data collection top

Bruker APEXII CCD diffractometer	4069 independent reflections
Radiation source: fine-focus sealed tube	3678 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.014
ω rotation with narrow frames scans	θ_max = 30.6°, θ_min = 2.6°
Absorption correction: multi-scan (SADABS; Sheldrick, 2007)	h = −11→11
T_min = 0.867, T_max = 0.975	k = −11→11
8153 measured reflections	l = −15→15

Refinement top

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)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.096	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0555P)² + 0.1549P] where P = (F_o² + 2F_c²)/3
4069 reflections	(Δ/σ)_max < 0.001
184 parameters	Δρ_max = 0.47 e Å⁻³
0 restraints	Δρ_min = −0.34 e Å⁻³

Crystal data top

C₁₃H₁₅NO₅S	γ = 79.3434 (7)°
M_r = 297.32	V = 677.33 (6) Å³
Triclinic, P1	Z = 2
a = 7.9810 (4) Å	Mo Kα radiation
b = 8.1215 (4) Å	µ = 0.26 mm⁻¹
c = 10.8173 (6) Å	T = 150 K
α = 89.4783 (7)°	0.57 × 0.17 × 0.10 mm
β = 79.5124 (8)°

Data collection top

Bruker APEXII CCD diffractometer	4069 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2007)	3678 reflections with I > 2σ(I)
T_min = 0.867, T_max = 0.975	R_int = 0.014
8153 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.033	0 restraints
wR(F²) = 0.096	H-atom parameters constrained
S = 1.07	Δρ_max = 0.47 e Å⁻³
4069 reflections	Δρ_min = −0.34 e Å⁻³
184 parameters

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
N1	0.37350 (11)	0.28852 (10)	0.19858 (8)	0.01854 (16)
C11	0.32384 (14)	0.38127 (14)	0.08880 (10)	0.0245 (2)
H11A	0.4141	0.3475	0.0145	0.037*
H11B	0.3107	0.5019	0.1052	0.037*
H11C	0.2137	0.3560	0.0738	0.037*
S1	0.24645 (3)	0.32872 (3)	0.33583 (2)	0.02022 (8)
O1	0.34949 (12)	0.28319 (11)	0.43054 (8)	0.02893 (18)
O2	0.15077 (12)	0.49632 (10)	0.33569 (9)	0.0320 (2)
C1	0.10979 (13)	0.18357 (12)	0.33574 (9)	0.01836 (18)
C2	−0.06595 (13)	0.22200 (14)	0.38733 (10)	0.0230 (2)
H2	−0.1177	0.3311	0.4207	0.028*
C3	−0.16426 (14)	0.09717 (16)	0.38904 (10)	0.0268 (2)
H3	−0.2851	0.1213	0.4223	0.032*
C4	−0.08623 (15)	−0.06293 (15)	0.34218 (10)	0.0259 (2)
H4	−0.1538	−0.1483	0.3463	0.031*
C5	0.08906 (14)	−0.09988 (13)	0.28949 (10)	0.02141 (19)
H5	0.1406	−0.2099	0.2580	0.026*
C6	0.18987 (12)	0.02506 (12)	0.28280 (9)	0.01735 (17)
C7	0.37251 (12)	−0.00786 (12)	0.21908 (9)	0.01697 (17)
O3	0.45163 (10)	−0.17111 (9)	0.19875 (7)	0.02058 (15)
C12	0.49827 (15)	−0.25298 (13)	0.31109 (10)	0.0239 (2)
H12A	0.3954	−0.2867	0.3633	0.029*
H12B	0.5423	−0.1753	0.3617	0.029*
C13	0.63614 (18)	−0.40461 (15)	0.27026 (14)	0.0356 (3)
H13A	0.5911	−0.4810	0.2207	0.053*
H13B	0.6698	−0.4619	0.3446	0.053*
H13C	0.7375	−0.3699	0.2189	0.053*
C8	0.45807 (12)	0.11773 (12)	0.17707 (9)	0.01727 (17)
C9	0.64295 (13)	0.08859 (13)	0.11182 (9)	0.01947 (18)
O4	0.72988 (11)	−0.04393 (11)	0.07302 (9)	0.0333 (2)
O5	0.70186 (10)	0.23360 (10)	0.10291 (8)	0.02397 (16)
C10	0.88320 (14)	0.21929 (15)	0.04958 (11)	0.0264 (2)
H10A	0.9526	0.1425	0.0994	0.040*
H10B	0.9156	0.3299	0.0503	0.040*
H10C	0.9047	0.1758	−0.0372	0.040*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0194 (4)	0.0142 (3)	0.0198 (4)	−0.0011 (3)	0.0003 (3)	0.0009 (3)
C11	0.0246 (5)	0.0219 (5)	0.0254 (5)	−0.0017 (4)	−0.0033 (4)	0.0062 (4)
S1	0.02258 (13)	0.01530 (12)	0.02126 (13)	−0.00367 (9)	0.00029 (9)	−0.00292 (8)
O1	0.0339 (4)	0.0336 (4)	0.0221 (4)	−0.0119 (3)	−0.0065 (3)	−0.0039 (3)
O2	0.0330 (4)	0.0152 (4)	0.0405 (5)	−0.0009 (3)	0.0084 (4)	−0.0039 (3)
C1	0.0194 (4)	0.0180 (4)	0.0173 (4)	−0.0033 (3)	−0.0025 (3)	0.0017 (3)
C2	0.0203 (4)	0.0257 (5)	0.0204 (4)	−0.0009 (4)	−0.0006 (4)	0.0008 (4)
C3	0.0194 (4)	0.0379 (6)	0.0230 (5)	−0.0080 (4)	−0.0015 (4)	0.0020 (4)
C4	0.0243 (5)	0.0325 (5)	0.0246 (5)	−0.0137 (4)	−0.0058 (4)	0.0048 (4)
C5	0.0241 (5)	0.0204 (4)	0.0219 (4)	−0.0074 (4)	−0.0067 (4)	0.0027 (4)
C6	0.0184 (4)	0.0171 (4)	0.0169 (4)	−0.0035 (3)	−0.0039 (3)	0.0019 (3)
C7	0.0189 (4)	0.0143 (4)	0.0175 (4)	−0.0017 (3)	−0.0041 (3)	−0.0008 (3)
O3	0.0266 (4)	0.0134 (3)	0.0204 (3)	−0.0003 (3)	−0.0040 (3)	−0.0010 (2)
C12	0.0284 (5)	0.0179 (4)	0.0251 (5)	0.0011 (4)	−0.0094 (4)	0.0004 (4)
C13	0.0396 (7)	0.0210 (5)	0.0446 (7)	0.0095 (5)	−0.0183 (6)	−0.0072 (5)
C8	0.0171 (4)	0.0153 (4)	0.0185 (4)	−0.0014 (3)	−0.0023 (3)	−0.0010 (3)
C9	0.0186 (4)	0.0202 (4)	0.0190 (4)	−0.0033 (3)	−0.0022 (3)	−0.0012 (3)
O4	0.0237 (4)	0.0231 (4)	0.0472 (5)	−0.0014 (3)	0.0062 (4)	−0.0086 (4)
O5	0.0175 (3)	0.0207 (3)	0.0323 (4)	−0.0045 (3)	0.0003 (3)	−0.0009 (3)
C10	0.0176 (4)	0.0304 (5)	0.0299 (5)	−0.0059 (4)	0.0002 (4)	0.0026 (4)

Geometric parameters (Å, º) top

N1—C8	1.4270 (12)	C5—H5	0.9500
N1—C11	1.4762 (13)	C6—C7	1.4713 (13)
N1—S1	1.6363 (9)	C7—C8	1.3599 (13)
C11—H11A	0.9800	C7—O3	1.3602 (11)
C11—H11B	0.9800	O3—C12	1.4546 (12)
C11—H11C	0.9800	C12—C13	1.5014 (15)
S1—O1	1.4318 (9)	C12—H12A	0.9900
S1—O2	1.4324 (8)	C12—H12B	0.9900
S1—C1	1.7479 (10)	C13—H13A	0.9800
C1—C2	1.3901 (14)	C13—H13B	0.9800
C1—C6	1.4035 (13)	C13—H13C	0.9800
C2—C3	1.3900 (16)	C8—C9	1.4920 (13)
C2—H2	0.9500	C9—O4	1.2008 (13)
C3—C4	1.3904 (17)	C9—O5	1.3429 (12)
C3—H3	0.9500	O5—C10	1.4409 (12)
C4—C5	1.3891 (15)	C10—H10A	0.9800
C4—H4	0.9500	C10—H10B	0.9800
C5—C6	1.4006 (14)	C10—H10C	0.9800

C8—N1—C11	116.99 (8)	C5—C6—C7	120.92 (9)
C8—N1—S1	114.71 (6)	C1—C6—C7	121.18 (9)
C11—N1—S1	118.75 (7)	C8—C7—O3	120.74 (9)
N1—C11—H11A	109.5	C8—C7—C6	122.18 (9)
N1—C11—H11B	109.5	O3—C7—C6	117.02 (8)
H11A—C11—H11B	109.5	C7—O3—C12	113.59 (7)
N1—C11—H11C	109.5	O3—C12—C13	107.98 (9)
H11A—C11—H11C	109.5	O3—C12—H12A	110.1
H11B—C11—H11C	109.5	C13—C12—H12A	110.1
O1—S1—O2	119.30 (6)	O3—C12—H12B	110.1
O1—S1—N1	107.81 (5)	C13—C12—H12B	110.1
O2—S1—N1	108.08 (5)	H12A—C12—H12B	108.4
O1—S1—C1	108.19 (5)	C12—C13—H13A	109.5
O2—S1—C1	110.56 (5)	C12—C13—H13B	109.5
N1—S1—C1	101.38 (5)	H13A—C13—H13B	109.5
C2—C1—C6	122.35 (9)	C12—C13—H13C	109.5
C2—C1—S1	122.00 (8)	H13A—C13—H13C	109.5
C6—C1—S1	115.63 (7)	H13B—C13—H13C	109.5
C3—C2—C1	118.52 (10)	C7—C8—N1	120.24 (9)
C3—C2—H2	120.7	C7—C8—C9	123.51 (9)
C1—C2—H2	120.7	N1—C8—C9	116.22 (8)
C2—C3—C4	120.16 (10)	O4—C9—O5	123.71 (9)
C2—C3—H3	119.9	O4—C9—C8	126.14 (9)
C4—C3—H3	119.9	O5—C9—C8	110.15 (8)
C5—C4—C3	120.97 (10)	C9—O5—C10	115.19 (8)
C5—C4—H4	119.5	O5—C10—H10A	109.5
C3—C4—H4	119.5	O5—C10—H10B	109.5
C4—C5—C6	120.01 (10)	H10A—C10—H10B	109.5
C4—C5—H5	120.0	O5—C10—H10C	109.5
C6—C5—H5	120.0	H10A—C10—H10C	109.5
C5—C6—C1	117.87 (9)	H10B—C10—H10C	109.5

C8—N1—S1—O1	58.91 (8)	S1—C1—C6—C7	−6.73 (12)
C11—N1—S1—O1	−155.79 (8)	C5—C6—C7—C8	159.51 (10)
C8—N1—S1—O2	−170.89 (7)	C1—C6—C7—C8	−18.73 (14)
C11—N1—S1—O2	−25.58 (9)	C5—C6—C7—O3	−17.78 (13)
C8—N1—S1—C1	−54.62 (8)	C1—C6—C7—O3	163.98 (9)
C11—N1—S1—C1	90.69 (8)	C8—C7—O3—C12	106.82 (11)
O1—S1—C1—C2	104.51 (9)	C6—C7—O3—C12	−75.85 (11)
O2—S1—C1—C2	−27.82 (10)	C7—O3—C12—C13	−159.92 (9)
N1—S1—C1—C2	−142.26 (9)	O3—C7—C8—N1	179.78 (8)
O1—S1—C1—C6	−74.15 (9)	C6—C7—C8—N1	2.59 (14)
O2—S1—C1—C6	153.53 (8)	O3—C7—C8—C9	−2.63 (15)
N1—S1—C1—C6	39.09 (8)	C6—C7—C8—C9	−179.82 (9)
C6—C1—C2—C3	1.63 (15)	C11—N1—C8—C7	−107.70 (11)
S1—C1—C2—C3	−176.93 (8)	S1—N1—C8—C7	38.24 (12)
C1—C2—C3—C4	1.25 (16)	C11—N1—C8—C9	74.55 (11)
C2—C3—C4—C5	−2.02 (17)	S1—N1—C8—C9	−139.52 (8)
C3—C4—C5—C6	−0.10 (16)	C7—C8—C9—O4	11.14 (17)
C4—C5—C6—C1	2.85 (15)	N1—C8—C9—O4	−171.18 (10)
C4—C5—C6—C7	−175.45 (9)	C7—C8—C9—O5	−168.23 (9)
C2—C1—C6—C5	−3.67 (15)	N1—C8—C9—O5	9.45 (12)
S1—C1—C6—C5	174.98 (7)	O4—C9—O5—C10	−3.71 (15)
C2—C1—C6—C7	174.62 (9)	C8—C9—O5—C10	175.68 (8)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···O2ⁱ	0.95	2.51	3.2726 (13)	137
C13—H13A···O5ⁱ	0.98	2.58	3.3715 (15)	138

Symmetry code: (i) x, y−1, z.

Experimental details

Crystal data
Chemical formula	C₁₃H₁₅NO₅S
M_r	297.32
Crystal system, space group	Triclinic, P1
Temperature (K)	150
a, b, c (Å)	7.9810 (4), 8.1215 (4), 10.8173 (6)
α, β, γ (°)	89.4783 (7), 79.5124 (8), 79.3434 (7)
V (Å³)	677.33 (6)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.26
Crystal size (mm)	0.57 × 0.17 × 0.10

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2007)
T_min, T_max	0.867, 0.975
No. of measured, independent and observed [I > 2σ(I)] reflections	8153, 4069, 3678
R_int	0.014
(sin θ/λ)_max (Å⁻¹)	0.715

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.096, 1.07
No. of reflections	4069
No. of parameters	184
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.47, −0.34

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXTL (Sheldrick, 2008) and local programs.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···O2ⁱ	0.95	2.51	3.2726 (13)	137
C13—H13A···O5ⁱ	0.98	2.58	3.3715 (15)	138

Symmetry code: (i) x, y−1, z.

Acknowledgements

We are grateful to PCSIR Laboratories Complex, Lahore, for the provision of necessary chemicals.

References

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