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

Ahmad, M.; Siddiqui, H.L.; Ahmad, S.; Irfan Ashiq, M.; Tizzard, G.J.

doi:10.1107/S1600536808004029

organic compounds

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ISSN: 2056-9890

Volume 64| Part 3| March 2008| Page o594

doi:10.1107/S1600536808004029

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

Matloob Ahmad,^a Hamid Latif Siddiqui,^a ^* Saeed Ahmad,^b Muhammad Irfan Ashiq ^a and Graham John Tizzard ^c

^aInstitute of Chemistry, University of the Punjab, Lahore 54600, Pakistan, ^bDepartment of Chemistry, University of Science and Technology, Bannu, Pakistan, and ^cSchool of Chemistry, University of Southampton, England
^*Correspondence e-mail: drhamidlatif@yahoo.com

(Received 12 December 2007; accepted 7 February 2008; online 15 February 2008)

In the title compound, C₁₃H₁₃NO₆S, the thiazine ring adopts a distorted half-chair conformation. Each molecule is linked to its neighbour through intermolecular C—H⋯O hydrogen bonds.

Related literature

For related literature, see: Fabiola et al. (1998 ); Golič & Leban (1987 ); Kojić-Prodić & Rużić-Toroš (1982 ); Rajagopal & Seshadri (1990 ); Reck et al. (1988 ); Rehman et al. (2005 , 2006 ); Turck et al. (1996 ).

Experimental

Crystal data

C₁₃H₁₃NO₆S
M_r = 311.30
Monoclinic, P 2₁ /c
a = 6.8917 (5) Å
b = 24.1814 (17) Å
c = 8.2861 (5) Å
β = 97.876 (4)°
V = 1367.86 (16) Å³
Z = 4
Mo Kα radiation
μ = 0.26 mm⁻¹
T = 120 (2) K
0.40 × 0.20 × 0.20 mm

Data collection

Bruker Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2007 ) T_min = 0.902, T_max = 0.949
12265 measured reflections
3032 independent reflections
2183 reflections with I > 2σ(I)
R_int = 0.057

Refinement

R[F² > 2σ(F²)] = 0.050
wR(F²) = 0.145
S = 1.03
3032 reflections
193 parameters
H-atom parameters constrained
Δρ_max = 0.36 e Å⁻³
Δρ_min = −0.55 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C13—H13A⋯O4ⁱ	0.98	2.48	3.387 (3)	153
C5—H5⋯O1ⁱ	0.95	2.48	3.349 (3)	151
Symmetry code: (i) x, y, z-1.

Data collection: COLLECT (Nonius, 1998 ); cell refinement: DENZO (Otwinowski & Minor, 1997 ) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CAMERON (Pearce & Watkin, 1993 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808004029/kp2156sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808004029/kp2156Isup2.hkl

checkCIF report

Comment top

Among the vast class of benzothiazines, 1,2-benzothiazine1,1-dioxides are the most versatile compounds due to their applications in various fields such as pharmaceuticals (Turck et al., 1996), dyes (Rajagopal & Seshadri, 1990) and fungicides. In continuation of our investigation of the chemistry of 1,2-benzothiazine 1,1-dioxide derivatives (Rehman et al., 2005; Rehman et al., 2006) we have synthesized the title compound (I) and its crystal structure is reported here.

In (I) (Fig. 1), the benzene ring of the benzothiazine nucleus is planar (the maximum least square deviation from the plane of the atoms involved is 0.01 Å) while the thiazine ring adopts a distorted half chair conformation. N1 has a pyramidal geometry projecting the methyl group approximately perpendicular to the thiazine ring. Atoms O1, O3 and O5 lie approximately in the plane of the ring while O2 lies almost perpendicular to it.

The C7—O3 bond length in (I) is longer [1.389 (3)] than in the related molecules having no substitution at O3 [1.352 (9) Å; Golič & Leban, 1987; 1.350 (9) Å; Reck et al., 1988].

C9—O4 bond length [1.201 (13) Å] is observed to be shorter than in its previously reported non acylated analogue [1.262 (10) Å; Golič & Leban, 1987] due to no involvement of O4 electrons in the hydrogen bonding. O4 lies almost perpendicular to the thiazine ring and the bond angle C7—C8—C9 [127.3 (2) Å] is greater than observed in the related hydrogen bonded oxicams [121.0 (3) Å; Kojić-Prodić & Rużić-Toroš, 1982; 120.9 (2) Å, Fabiola et al., 1998]. Molecules are linked by C—H···O hydrogen bonds (Table1) forming a chain along a axis.

Related literature top

For related literature, see: Fabiola et al. (1998); Golič & Leban (1987); Kojić-Prodić & Rużić-Toroš (1982); Rajagopal & Seshadri (1990); Reck et al. (1988); Rehman et al. (2005, 2006); Turck et al. (1996).

Experimental top

Acetyl chloride (1.57 g; 10 mmol) was slowly added to a mixture of methyl 4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate1,1-dioxide (1.345 g; 5 mmol), triethylamine (0.71 g; 7 mmol) and carbon tetrachloride (25 ml) under nitrogen atmosphere at 273 K. The mixture was stirred for a period of three hours at room temperature and the solvent was evaporated under vacuum. A residue was poured over ice-water mixture to get the white coloured product which was washed with cold water and recrystallized from chloroform-methanol mixture (1:1). Yield 1.31 g; 84°; m.p. 422 K.

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1998); data reduction: DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CAMERON (Pearce & Watkin, 1993); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

Fig. 1. The molecular structure of (I), showing displacement ellipsoids at the 50% probability level for non-H atoms. Dashed lines denote hydrogen bonds.

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

Crystal data top

C₁₃H₁₃NO₆S	F(000) = 648
M_r = 311.30	D_x = 1.512 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 15145 reflections
a = 6.8917 (5) Å	θ = 2.9–27.5°
b = 24.1814 (17) Å	µ = 0.26 mm⁻¹
c = 8.2861 (5) Å	T = 120 K
β = 97.876 (4)°	Block, colourless
V = 1367.86 (16) Å³	0.40 × 0.20 × 0.20 mm
Z = 4

Data collection top

Bruker Nonius CCD camera on κ-goniostat diffractometer	3032 independent reflections
Radiation source: Bruker Nonius FR591 Rotating Anode	2183 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.057
Detector resolution: 9.091 pixels mm^-1	θ_max = 27.5°, θ_min = 3.0°
ϕ and ω scans to fill the asymmetric unit	h = −8→8
Absorption correction: multi-scan (SADABS; Sheldrick, 2007)	k = −31→30
T_min = 0.902, T_max = 0.949	l = −10→9
12265 measured reflections

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)] = 0.050	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.145	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0764P)² + 0.6225P] where P = (F_o² + 2F_c²)/3
3032 reflections	(Δ/σ)_max = 0.001
193 parameters	Δρ_max = 0.36 e Å⁻³
0 restraints	Δρ_min = −0.55 e Å⁻³

Crystal data top

C₁₃H₁₃NO₆S	V = 1367.86 (16) Å³
M_r = 311.30	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 6.8917 (5) Å	µ = 0.26 mm⁻¹
b = 24.1814 (17) Å	T = 120 K
c = 8.2861 (5) Å	0.40 × 0.20 × 0.20 mm
β = 97.876 (4)°

Data collection top

Bruker Nonius CCD camera on κ-goniostat diffractometer	3032 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2007)	2183 reflections with I > 2σ(I)
T_min = 0.902, T_max = 0.949	R_int = 0.057
12265 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.050	0 restraints
wR(F²) = 0.145	H-atom parameters constrained
S = 1.03	Δρ_max = 0.36 e Å⁻³
3032 reflections	Δρ_min = −0.55 e Å⁻³
193 parameters

Special details top

Experimental. SADABS was used to perform the Absorption correction Estimated minimum and maximum transmission: 0.6195 0.7456 The given Tmin and Tmax were generated using the SHELX SIZE command

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
C1	0.5172 (4)	0.43090 (10)	0.7387 (3)	0.0183 (5)
C2	0.7043 (4)	0.45347 (10)	0.7686 (3)	0.0213 (6)
H2	0.7629	0.4616	0.8766	0.026*
C3	0.8032 (4)	0.46376 (10)	0.6369 (3)	0.0213 (5)
H3	0.9315	0.4790	0.6544	0.026*
C4	0.7153 (4)	0.45192 (10)	0.4788 (3)	0.0219 (6)
H4	0.7836	0.4597	0.3893	0.026*
C5	0.5299 (4)	0.42895 (9)	0.4508 (3)	0.0183 (5)
H5	0.4719	0.4211	0.3425	0.022*
C6	0.4276 (4)	0.41729 (9)	0.5809 (3)	0.0167 (5)
C7	0.2364 (3)	0.39001 (9)	0.5570 (3)	0.0162 (5)
C8	0.1613 (4)	0.36162 (10)	0.6749 (3)	0.0181 (5)
C9	−0.0253 (4)	0.32911 (10)	0.6577 (3)	0.0202 (6)
C10	−0.2808 (4)	0.28845 (11)	0.4788 (3)	0.0301 (6)
H10A	−0.2544	0.2510	0.5215	0.045*
H10B	−0.3298	0.2865	0.3622	0.045*
H10C	−0.3793	0.3061	0.5364	0.045*
C11	0.3594 (4)	0.30948 (11)	0.8954 (3)	0.0294 (7)
H11A	0.2711	0.2784	0.8643	0.044*
H11B	0.3914	0.3107	1.0143	0.044*
H11C	0.4800	0.3048	0.8464	0.044*
C12	0.1291 (4)	0.35858 (10)	0.2862 (3)	0.0207 (6)
C13	−0.0222 (4)	0.37189 (12)	0.1456 (3)	0.0307 (7)
H13A	−0.0128	0.3455	0.0572	0.046*
H13B	−0.0008	0.4094	0.1073	0.046*
H13C	−0.1526	0.3695	0.1796	0.046*
N1	0.2622 (3)	0.36187 (8)	0.8366 (2)	0.0185 (5)
O1	0.4912 (3)	0.41115 (8)	1.04687 (19)	0.0263 (4)
O2	0.2249 (3)	0.46261 (7)	0.8823 (2)	0.0234 (4)
O3	0.1272 (2)	0.39845 (6)	0.40526 (18)	0.0184 (4)
O4	−0.0967 (3)	0.31203 (8)	0.7727 (2)	0.0353 (5)
O5	−0.1014 (3)	0.32064 (7)	0.5028 (2)	0.0266 (4)
O6	0.2420 (3)	0.32061 (7)	0.3014 (2)	0.0282 (5)
S1	0.37225 (9)	0.42031 (2)	0.89441 (7)	0.0197 (2)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0191 (13)	0.0190 (12)	0.0169 (12)	0.0010 (10)	0.0030 (10)	0.0017 (9)
C2	0.0201 (14)	0.0197 (12)	0.0222 (13)	−0.0006 (10)	−0.0035 (10)	−0.0003 (10)
C3	0.0138 (13)	0.0196 (12)	0.0302 (14)	−0.0010 (10)	0.0021 (10)	0.0026 (11)
C4	0.0205 (14)	0.0207 (12)	0.0260 (13)	0.0023 (10)	0.0082 (10)	0.0032 (10)
C5	0.0193 (14)	0.0183 (12)	0.0175 (12)	0.0029 (10)	0.0034 (10)	0.0009 (9)
C6	0.0162 (13)	0.0149 (11)	0.0182 (12)	0.0021 (9)	−0.0003 (10)	0.0017 (9)
C7	0.0146 (12)	0.0198 (12)	0.0135 (11)	0.0019 (10)	−0.0006 (9)	−0.0019 (9)
C8	0.0204 (14)	0.0183 (12)	0.0151 (11)	0.0004 (10)	0.0009 (9)	−0.0017 (9)
C9	0.0214 (14)	0.0197 (12)	0.0201 (13)	0.0000 (10)	0.0047 (10)	−0.0040 (10)
C10	0.0250 (16)	0.0325 (15)	0.0320 (15)	−0.0132 (12)	0.0013 (12)	−0.0068 (12)
C11	0.0372 (17)	0.0243 (14)	0.0257 (14)	0.0046 (12)	0.0006 (12)	0.0038 (11)
C12	0.0186 (14)	0.0267 (13)	0.0175 (12)	−0.0040 (11)	0.0046 (10)	−0.0015 (10)
C13	0.0280 (16)	0.0437 (17)	0.0190 (13)	−0.0027 (13)	−0.0015 (11)	−0.0039 (12)
N1	0.0192 (12)	0.0202 (10)	0.0157 (10)	−0.0012 (8)	0.0013 (8)	0.0007 (8)
O1	0.0243 (11)	0.0390 (11)	0.0141 (9)	−0.0034 (8)	−0.0023 (7)	0.0010 (8)
O2	0.0248 (10)	0.0230 (9)	0.0223 (9)	0.0011 (7)	0.0031 (7)	−0.0041 (7)
O3	0.0176 (9)	0.0218 (9)	0.0152 (8)	0.0003 (7)	−0.0003 (7)	−0.0008 (7)
O4	0.0386 (13)	0.0458 (12)	0.0225 (10)	−0.0196 (10)	0.0080 (9)	0.0008 (9)
O5	0.0222 (10)	0.0351 (10)	0.0223 (9)	−0.0119 (8)	0.0020 (7)	−0.0044 (8)
O6	0.0308 (11)	0.0284 (10)	0.0259 (10)	0.0028 (8)	0.0054 (8)	−0.0049 (8)
S1	0.0207 (4)	0.0234 (3)	0.0147 (3)	−0.0017 (2)	0.0014 (2)	−0.0012 (2)

Geometric parameters (Å, º) top

C1—C2	1.391 (3)	C10—O5	1.451 (3)
C1—C6	1.407 (3)	C10—H10A	0.9800
C1—S1	1.755 (3)	C10—H10B	0.9800
C2—C3	1.386 (4)	C10—H10C	0.9800
C2—H2	0.9500	C11—N1	1.484 (3)
C3—C4	1.396 (3)	C11—H11A	0.9800
C3—H3	0.9500	C11—H11B	0.9800
C4—C5	1.384 (3)	C11—H11C	0.9800
C4—H4	0.9500	C12—O6	1.199 (3)
C5—C6	1.396 (3)	C12—O3	1.380 (3)
C5—H5	0.9500	C12—C13	1.488 (3)
C6—C7	1.463 (3)	C13—H13A	0.9800
C7—C8	1.353 (3)	C13—H13B	0.9800
C7—O3	1.389 (3)	C13—H13C	0.9800
C8—N1	1.422 (3)	N1—S1	1.644 (2)
C8—C9	1.498 (3)	O1—S1	1.4258 (17)
C9—O4	1.203 (3)	O2—S1	1.4354 (18)
C9—O5	1.334 (3)

C2—C1—C6	122.4 (2)	O5—C10—H10C	109.5
C2—C1—S1	122.25 (18)	H10A—C10—H10C	109.5
C6—C1—S1	115.33 (18)	H10B—C10—H10C	109.5
C3—C2—C1	118.3 (2)	N1—C11—H11A	109.5
C3—C2—H2	120.8	N1—C11—H11B	109.5
C1—C2—H2	120.8	H11A—C11—H11B	109.5
C2—C3—C4	120.4 (2)	N1—C11—H11C	109.5
C2—C3—H3	119.8	H11A—C11—H11C	109.5
C4—C3—H3	119.8	H11B—C11—H11C	109.5
C5—C4—C3	120.8 (2)	O6—C12—O3	121.9 (2)
C5—C4—H4	119.6	O6—C12—C13	128.5 (2)
C3—C4—H4	119.6	O3—C12—C13	109.5 (2)
C4—C5—C6	120.3 (2)	C12—C13—H13A	109.5
C4—C5—H5	119.9	C12—C13—H13B	109.5
C6—C5—H5	119.9	H13A—C13—H13B	109.5
C5—C6—C1	117.9 (2)	C12—C13—H13C	109.5
C5—C6—C7	121.9 (2)	H13A—C13—H13C	109.5
C1—C6—C7	120.2 (2)	H13B—C13—H13C	109.5
C8—C7—O3	121.0 (2)	C8—N1—C11	116.50 (18)
C8—C7—C6	123.9 (2)	C8—N1—S1	115.14 (15)
O3—C7—C6	114.97 (19)	C11—N1—S1	117.95 (17)
C7—C8—N1	119.5 (2)	C12—O3—C7	119.17 (18)
C7—C8—C9	127.3 (2)	C9—O5—C10	115.4 (2)
N1—C8—C9	113.2 (2)	O1—S1—O2	119.20 (10)
O4—C9—O5	124.0 (2)	O1—S1—N1	108.13 (11)
O4—C9—C8	123.0 (2)	O2—S1—N1	107.37 (10)
O5—C9—C8	113.0 (2)	O1—S1—C1	110.97 (12)
O5—C10—H10A	109.5	O2—S1—C1	108.25 (11)
O5—C10—H10B	109.5	N1—S1—C1	101.39 (11)
H10A—C10—H10B	109.5

C6—C1—C2—C3	1.3 (4)	C7—C8—N1—C11	−108.8 (3)
S1—C1—C2—C3	−175.79 (18)	C9—C8—N1—C11	72.3 (3)
C1—C2—C3—C4	0.4 (4)	C7—C8—N1—S1	35.6 (3)
C2—C3—C4—C5	−1.1 (4)	C9—C8—N1—S1	−143.34 (17)
C3—C4—C5—C6	0.1 (4)	O6—C12—O3—C7	−10.5 (3)
C4—C5—C6—C1	1.6 (3)	C13—C12—O3—C7	170.6 (2)
C4—C5—C6—C7	−176.3 (2)	C8—C7—O3—C12	−86.4 (3)
C2—C1—C6—C5	−2.3 (3)	C6—C7—O3—C12	98.0 (2)
S1—C1—C6—C5	175.01 (17)	O4—C9—O5—C10	−0.2 (4)
C2—C1—C6—C7	175.6 (2)	C8—C9—O5—C10	178.9 (2)
S1—C1—C6—C7	−7.1 (3)	C8—N1—S1—O1	−170.76 (17)
C5—C6—C7—C8	157.1 (2)	C11—N1—S1—O1	−27.0 (2)
C1—C6—C7—C8	−20.7 (4)	C8—N1—S1—O2	59.42 (19)
C5—C6—C7—O3	−27.4 (3)	C11—N1—S1—O2	−156.78 (18)
C1—C6—C7—O3	154.8 (2)	C8—N1—S1—C1	−54.01 (19)
O3—C7—C8—N1	−169.13 (19)	C11—N1—S1—C1	89.79 (19)
C6—C7—C8—N1	6.2 (4)	C2—C1—S1—O1	−28.5 (2)
O3—C7—C8—C9	9.6 (4)	C6—C1—S1—O1	154.23 (17)
C6—C7—C8—C9	−175.1 (2)	C2—C1—S1—O2	104.1 (2)
C7—C8—C9—O4	−168.4 (3)	C6—C1—S1—O2	−73.2 (2)
N1—C8—C9—O4	10.4 (3)	C2—C1—S1—N1	−143.1 (2)
C7—C8—C9—O5	12.4 (4)	C6—C1—S1—N1	39.6 (2)
N1—C8—C9—O5	−168.8 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C13—H13A···O4ⁱ	0.98	2.49	3.387 (3)	153
C5—H5···O1ⁱ	0.95	2.48	3.349 (3)	151

Symmetry code: (i) x, y, z−1.

Experimental details

Crystal data
Chemical formula	C₁₃H₁₃NO₆S
M_r	311.30
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	120
a, b, c (Å)	6.8917 (5), 24.1814 (17), 8.2861 (5)
β (°)	97.876 (4)
V (Å³)	1367.86 (16)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.26
Crystal size (mm)	0.40 × 0.20 × 0.20

Data collection
Diffractometer	Bruker Nonius CCD camera on κ-goniostat diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2007)
T_min, T_max	0.902, 0.949
No. of measured, independent and observed [I > 2σ(I)] reflections	12265, 3032, 2183
R_int	0.057
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.050, 0.145, 1.03
No. of reflections	3032
No. of parameters	193
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.36, −0.55

Computer programs: , DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), CAMERON (Pearce & Watkin, 1993), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C13—H13A···O4ⁱ	0.98	2.485	3.387 (3)	153
C5—H5···O1ⁱ	0.95	2.483	3.349 (3)	151

Symmetry code: (i) x, y, z−1.

Acknowledgements

The authors acknowledge financial support from the Higher Education Commission of Pakistan and the University of the Punjab, Lahore.

References

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