Propan-2-yl 2-(1,1,3-trioxo-2,3-dihydro-1λ6,2-benzothia­zol-2-yl)acetate

Zia-ur-Rehman, M.; Shahid, B.; Siddiqui, H.L.; Ahmad, T.; Parvez, M.

doi:10.1107/S1600536812036148

organic compounds

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ISSN: 2056-9890

Volume 68| Part 9| September 2012| Page o2761

doi:10.1107/S1600536812036148

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Propan-2-yl 2-(1,1,3-trioxo-2,3-dihydro-1λ⁶,2-benzothiazol-2-yl)acetate

Muhammad Zia-ur-Rehman,^a ^* Bilal Shahid,^b Hamid Latif Siddiqui,^b Tanveer Ahmad ^b and Masood Parvez ^c

^aApplied Chemistry Research Centre, PCSIR Laboratories Complex, Lahore 54600, Pakistan, ^bInstitute of Chemistry, University of the Punjab, Lahore 54590, Pakistan, and ^cDepartment of Chemistry, The University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
^*Correspondence e-mail: rehman_pcsir@hotmail.com

(Received 12 August 2012; accepted 16 August 2012; online 23 August 2012)

In the title molecule, C₁₂H₁₃NO₅S, the benzisothiazole ring system is essentially planar (r.m.s. deviation = 0.0169 Å) as is the –C—C(=O)—O—C– sequence of atoms in the vicinity of the acetate group (r.m.s. deviation = 0.0044 Å). The mean plane of these atoms forms a dihedral angle of 88.41 (7)° with the benzisothiazole ring system. In the crystal, weak C—H⋯O hydrogen bonds involving methylene and methyne H atoms form R₄³(20) graph-set motifs.

Related literature

For uses of 1,2-benzothiazol-3(2H)-one 1,1-dioxide, see: Kap-Sun & Nicholas (1998 ). For the synthesis of non-steroidal anti-inflammatory drugs (NSAIDs) and their biological evaluation, see: Ahmad et al. (2011 ); Zia-ur-Rehman et al. (2009 ). For related structures, see: Sattar et al. (2012 ); Maliha et al. (2007 ); Siddiqui et al. (2007 ). For graph-set motifs, see: (Bernstein et al., 1995 ).

Experimental

Crystal data

C₁₂H₁₃NO₅S
M_r = 283.29
Monoclinic, P 2₁ /n
a = 8.0922 (3) Å
b = 9.2314 (4) Å
c = 17.7414 (8) Å
β = 100.075 (2)°
V = 1304.89 (9) Å³
Z = 4
Mo Kα radiation
μ = 0.26 mm⁻¹
T = 173 K
0.14 × 0.12 × 0.06 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SORTAV; Blessing, 1997 ) T_min = 0.964, T_max = 0.984
5518 measured reflections
2953 independent reflections
2339 reflections with I > 2σ(I)
R_int = 0.041

Refinement

R[F² > 2σ(F²)] = 0.055
wR(F²) = 0.119
S = 1.11
2953 reflections
174 parameters
H-atom parameters constrained
Δρ_max = 0.41 e Å⁻³
Δρ_min = −0.43 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C8—H8B⋯O3ⁱ	0.99	2.27	3.236 (3)	166
C10—H10⋯O3ⁱⁱ	1.00	2.42	3.245 (3)	140
Symmetry codes: (i) $[-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (ii) x+1, y, z.

Data collection: COLLECT (Hooft, 1998 ); cell refinement: DENZO (Otwinowski & Minor, 1997 ); data reduction: SCALEPACK (Otwinowski & Minor, 1997); 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 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812036148/lh5516sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812036148/lh5516Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812036148/lh5516Isup3.cml

checkCIF report

Comment top

1,2-Benzothiazol-3(2H)-one 1,1-dioxide is known as an artificial sweetener commonly known as saccharin. It has been widely explored as a reactant of a number of medicinally important heterocyclic compounds (Kap-Sun & Nicholas, 1998), out of which oxicam family is the most important. N-alkylation of saccharin followed by base catalyzed ring expansion gives rise to methyl 4-hydroxy-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide (Zia-ur-Rehman et al., 2009) which is a basic precursor to the synthesis of Piroxicam, Meloxicam and Ampiroxicam. In continuation of our work on the synthesis and biological evaluation of thiazine based compounds (Ahmad et al., 2011), we herein report the crystal structure of the title compound.

In the title compound (Fig. 1), the benzisothiazol ring system S1/N1/C1–C7 is essentially planar with an r.m.s. deviation of the fitted atoms being 0.0169 Å. The O4/O5/C8-C10 sequence of atoms is also planar (r.m.s. deviation = 0.0044 Å) and forms a dihedral angle of 88.41 (7)° with the mean plane of the benzisothiazole ring system. The crystal packing is consolidated by weak intermolecular C—H···O hydrogen bonding interactions involving a H-atom of the methylene C8, C8—H8B···O3ⁱ, and a methyne H-atom bound to C10, C10—H10···O3ⁱⁱ, forming twenty membered rings in graph set motif R₄³(20) (Bernstein et al., 1995) (Fig. 2 & Tab. 1).

The bond distances and angles in the title compound agree very well with the corresponding bond distances and angles reported in closely related compounds (Sattar et al., 2012); Maliha et al., 2007; Siddiqui et al., 2007).

Related literature top

For uses of 1,2-benzothiazol-3(2H)-one 1,1-dioxide, see: Kap-Sun & Nicholas (1998). For the synthesis of non-steroidal anti-inflammatory drugs (NSAIDs) and their and biological evaluation, see: Ahmad et al. (2011); Zia-ur-Rehman et al. (2009). For related structures, see: Sattar et al. (2012); Maliha et al. (2007); Siddiqui et al. (2007). For graph-set motifs, see: (Bernstein et al., 1995).

Experimental top

A mixture of sodium saccharin (7.50 g; 36.55 mmol), N,N-dimethylformamide (50 ml) and isopropyl chloroacetate (4.99 g; 36.55 mmol) was taken in a round bottom flask and immersed in ultrasonic reaction bath at 333 K for a period of 15 min. The contents were then cooled to room temperature and poured over ice cooled water (300 ml) resulting in the formation of the title compound as a white solid, which was filtered and washed with cold water. The product was dried and recrystallized from isopropyl alcohol by slow evaporation to yield the crystal suitable for single crystal X-ray diffraction, yield = 94.4%; m.p. 392–394 K.

Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997); data reduction: SCALEPACK (Otwinowski & Minor, 1997); 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); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are shown as small spheres of arbitrary radius.

Fig. 2. A part of the crystal structure showing the C—H···O hydrogen bonds (dotted lines) forming R₄³(20) graph set motifs. H atoms not involved in hydrogen bonds are omitted for clarity.

Propan-2-yl 2-(1,1,3-trioxo-2,3-dihydro-1λ⁶,2-benzothiazol-2-yl)acetate top

Crystal data top

C₁₂H₁₃NO₅S	F(000) = 592
M_r = 283.29	D_x = 1.442 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2817 reflections
a = 8.0922 (3) Å	θ = 1.0–27.5°
b = 9.2314 (4) Å	µ = 0.26 mm⁻¹
c = 17.7414 (8) Å	T = 173 K
β = 100.075 (2)°	Prism, colorless
V = 1304.89 (9) Å³	0.14 × 0.12 × 0.06 mm
Z = 4

Data collection top

Nonius KappaCCD diffractometer	2953 independent reflections
Radiation source: fine-focus sealed tube	2339 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.041
ω and ϕ scans	θ_max = 27.4°, θ_min = 3.2°
Absorption correction: multi-scan (SORTAV; Blessing, 1997)	h = −10→10
T_min = 0.964, T_max = 0.984	k = −11→11
5518 measured reflections	l = −22→22

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)] = 0.055	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.119	H-atom parameters constrained
S = 1.11	w = 1/[σ²(F_o²) + (0.0186P)² + 1.8823P] where P = (F_o² + 2F_c²)/3
2953 reflections	(Δ/σ)_max = 0.001
174 parameters	Δρ_max = 0.41 e Å⁻³
0 restraints	Δρ_min = −0.43 e Å⁻³

Crystal data top

C₁₂H₁₃NO₅S	V = 1304.89 (9) Å³
M_r = 283.29	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 8.0922 (3) Å	µ = 0.26 mm⁻¹
b = 9.2314 (4) Å	T = 173 K
c = 17.7414 (8) Å	0.14 × 0.12 × 0.06 mm
β = 100.075 (2)°

Data collection top

Nonius KappaCCD diffractometer	2953 independent reflections
Absorption correction: multi-scan (SORTAV; Blessing, 1997)	2339 reflections with I > 2σ(I)
T_min = 0.964, T_max = 0.984	R_int = 0.041
5518 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.055	0 restraints
wR(F²) = 0.119	H-atom parameters constrained
S = 1.11	Δρ_max = 0.41 e Å⁻³
2953 reflections	Δρ_min = −0.43 e Å⁻³
174 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
S1	0.71458 (8)	0.28520 (7)	0.59318 (4)	0.02941 (18)
O1	0.6975 (3)	0.4281 (2)	0.62206 (12)	0.0414 (5)
O2	0.8538 (2)	0.2573 (2)	0.55647 (11)	0.0423 (5)
O3	0.5438 (2)	−0.0124 (2)	0.70065 (10)	0.0335 (4)
O4	0.9985 (3)	−0.0077 (2)	0.68519 (12)	0.0488 (6)
O5	1.0959 (2)	0.1079 (2)	0.79588 (10)	0.0311 (4)
N1	0.7092 (3)	0.1656 (2)	0.66356 (12)	0.0277 (5)
C1	0.5243 (3)	0.2216 (3)	0.54085 (13)	0.0250 (5)
C2	0.4415 (3)	0.2730 (3)	0.47085 (14)	0.0321 (6)
H2	0.4873	0.3475	0.4438	0.039*
C3	0.2872 (3)	0.2088 (3)	0.44250 (15)	0.0362 (7)
H3	0.2259	0.2407	0.3948	0.043*
C4	0.2206 (3)	0.1002 (3)	0.48162 (15)	0.0350 (6)
H4	0.1149	0.0594	0.4605	0.042*
C5	0.3061 (3)	0.0497 (3)	0.55150 (15)	0.0293 (6)
H5	0.2605	−0.0248	0.5786	0.035*
C6	0.4602 (3)	0.1119 (3)	0.58023 (13)	0.0234 (5)
C7	0.5697 (3)	0.0762 (3)	0.65414 (14)	0.0257 (5)
C8	0.8296 (3)	0.1713 (3)	0.73484 (14)	0.0314 (6)
H8A	0.7737	0.1390	0.7773	0.038*
H8B	0.8656	0.2730	0.7451	0.038*
C9	0.9831 (3)	0.0785 (3)	0.73385 (14)	0.0301 (6)
C10	1.2566 (3)	0.0297 (3)	0.80553 (16)	0.0350 (6)
H10	1.2916	0.0173	0.7546	0.042*
C11	1.3818 (4)	0.1243 (4)	0.8560 (2)	0.0526 (9)
H11A	1.4929	0.0790	0.8629	0.063*
H11B	1.3475	0.1359	0.9060	0.063*
H11C	1.3864	0.2195	0.8320	0.063*
C12	1.2351 (4)	−0.1147 (4)	0.8396 (2)	0.0501 (8)
H12A	1.3404	−0.1691	0.8444	0.060*
H12B	1.1458	−0.1680	0.8065	0.060*
H12C	1.2048	−0.1022	0.8903	0.060*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0286 (3)	0.0264 (3)	0.0310 (3)	−0.0029 (3)	−0.0007 (2)	0.0048 (3)
O1	0.0497 (12)	0.0242 (10)	0.0452 (12)	−0.0044 (9)	−0.0059 (9)	0.0021 (9)
O2	0.0295 (10)	0.0523 (13)	0.0462 (12)	−0.0056 (10)	0.0100 (9)	0.0067 (10)
O3	0.0376 (10)	0.0338 (10)	0.0291 (9)	0.0005 (9)	0.0057 (8)	0.0080 (8)
O4	0.0480 (13)	0.0531 (14)	0.0386 (11)	0.0179 (11)	−0.0107 (9)	−0.0165 (10)
O5	0.0254 (9)	0.0375 (11)	0.0275 (9)	0.0022 (8)	−0.0034 (7)	−0.0044 (8)
N1	0.0281 (11)	0.0263 (11)	0.0257 (11)	−0.0001 (9)	−0.0035 (9)	0.0036 (9)
C1	0.0239 (12)	0.0249 (12)	0.0253 (12)	0.0039 (10)	0.0019 (9)	−0.0003 (10)
C2	0.0324 (14)	0.0362 (15)	0.0280 (13)	0.0062 (12)	0.0057 (11)	0.0066 (12)
C3	0.0323 (14)	0.0452 (17)	0.0281 (13)	0.0119 (13)	−0.0035 (11)	0.0039 (13)
C4	0.0257 (13)	0.0436 (16)	0.0329 (14)	0.0012 (12)	−0.0027 (11)	−0.0058 (13)
C5	0.0258 (13)	0.0315 (14)	0.0309 (13)	0.0000 (11)	0.0063 (10)	−0.0037 (11)
C6	0.0241 (12)	0.0225 (12)	0.0235 (12)	0.0030 (10)	0.0039 (9)	0.0009 (10)
C7	0.0258 (12)	0.0255 (13)	0.0254 (12)	0.0030 (10)	0.0036 (10)	0.0005 (10)
C8	0.0332 (14)	0.0313 (14)	0.0259 (12)	0.0005 (11)	−0.0057 (11)	−0.0020 (11)
C9	0.0323 (14)	0.0310 (14)	0.0239 (12)	0.0017 (11)	−0.0033 (10)	−0.0005 (11)
C10	0.0240 (13)	0.0438 (16)	0.0369 (14)	0.0018 (12)	0.0047 (11)	−0.0011 (13)
C11	0.0359 (17)	0.055 (2)	0.061 (2)	−0.0069 (15)	−0.0066 (15)	0.0023 (17)
C12	0.0375 (17)	0.0480 (19)	0.062 (2)	0.0002 (15)	0.0017 (15)	0.0066 (17)

Geometric parameters (Å, º) top

S1—O2	1.420 (2)	C4—H4	0.9500
S1—O1	1.431 (2)	C5—C6	1.387 (3)
S1—N1	1.673 (2)	C5—H5	0.9500
S1—C1	1.754 (2)	C6—C7	1.485 (3)
O3—C7	1.206 (3)	C8—C9	1.511 (4)
O4—C9	1.197 (3)	C8—H8A	0.9900
O5—C9	1.329 (3)	C8—H8B	0.9900
O5—C10	1.471 (3)	C10—C12	1.486 (4)
N1—C7	1.385 (3)	C10—C11	1.508 (4)
N1—C8	1.456 (3)	C10—H10	1.0000
C1—C6	1.381 (3)	C11—H11A	0.9800
C1—C2	1.388 (3)	C11—H11B	0.9800
C2—C3	1.395 (4)	C11—H11C	0.9800
C2—H2	0.9500	C12—H12A	0.9800
C3—C4	1.381 (4)	C12—H12B	0.9800
C3—H3	0.9500	C12—H12C	0.9800
C4—C5	1.390 (4)

O2—S1—O1	117.72 (13)	O3—C7—C6	127.4 (2)
O2—S1—N1	110.45 (12)	N1—C7—C6	108.8 (2)
O1—S1—N1	108.93 (12)	N1—C8—C9	113.3 (2)
O2—S1—C1	112.96 (12)	N1—C8—H8A	108.9
O1—S1—C1	111.56 (12)	C9—C8—H8A	108.9
N1—S1—C1	92.23 (11)	N1—C8—H8B	108.9
C9—O5—C10	117.5 (2)	C9—C8—H8B	108.9
C7—N1—C8	122.3 (2)	H8A—C8—H8B	107.7
C7—N1—S1	115.50 (16)	O4—C9—O5	126.2 (2)
C8—N1—S1	121.56 (18)	O4—C9—C8	125.1 (2)
C6—C1—C2	122.6 (2)	O5—C9—C8	108.7 (2)
C6—C1—S1	110.48 (17)	O5—C10—C12	108.9 (2)
C2—C1—S1	126.9 (2)	O5—C10—C11	105.9 (2)
C1—C2—C3	116.0 (3)	C12—C10—C11	113.1 (3)
C1—C2—H2	122.0	O5—C10—H10	109.6
C3—C2—H2	122.0	C12—C10—H10	109.6
C4—C3—C2	122.1 (2)	C11—C10—H10	109.6
C4—C3—H3	119.0	C10—C11—H11A	109.5
C2—C3—H3	119.0	C10—C11—H11B	109.5
C3—C4—C5	121.0 (2)	H11A—C11—H11B	109.5
C3—C4—H4	119.5	C10—C11—H11C	109.5
C5—C4—H4	119.5	H11A—C11—H11C	109.5
C6—C5—C4	117.7 (3)	H11B—C11—H11C	109.5
C6—C5—H5	121.2	C10—C12—H12A	109.5
C4—C5—H5	121.2	C10—C12—H12B	109.5
C1—C6—C5	120.7 (2)	H12A—C12—H12B	109.5
C1—C6—C7	113.0 (2)	C10—C12—H12C	109.5
C5—C6—C7	126.3 (2)	H12A—C12—H12C	109.5
O3—C7—N1	123.9 (2)	H12B—C12—H12C	109.5

O2—S1—N1—C7	−116.8 (2)	S1—C1—C6—C7	−1.2 (3)
O1—S1—N1—C7	112.4 (2)	C4—C5—C6—C1	0.9 (4)
C1—S1—N1—C7	−1.3 (2)	C4—C5—C6—C7	178.7 (2)
O2—S1—N1—C8	72.3 (2)	C8—N1—C7—O3	−6.7 (4)
O1—S1—N1—C8	−58.4 (2)	S1—N1—C7—O3	−177.5 (2)
C1—S1—N1—C8	−172.1 (2)	C8—N1—C7—C6	171.6 (2)
O2—S1—C1—C6	114.72 (19)	S1—N1—C7—C6	0.8 (3)
O1—S1—C1—C6	−110.00 (19)	C1—C6—C7—O3	178.5 (3)
N1—S1—C1—C6	1.38 (19)	C5—C6—C7—O3	0.6 (4)
O2—S1—C1—C2	−67.2 (3)	C1—C6—C7—N1	0.3 (3)
O1—S1—C1—C2	68.1 (3)	C5—C6—C7—N1	−177.6 (2)
N1—S1—C1—C2	179.5 (2)	C7—N1—C8—C9	97.6 (3)
C6—C1—C2—C3	0.9 (4)	S1—N1—C8—C9	−92.1 (3)
S1—C1—C2—C3	−177.0 (2)	C10—O5—C9—O4	1.2 (4)
C1—C2—C3—C4	−0.1 (4)	C10—O5—C9—C8	−179.3 (2)
C2—C3—C4—C5	−0.2 (4)	N1—C8—C9—O4	−10.1 (4)
C3—C4—C5—C6	−0.2 (4)	N1—C8—C9—O5	170.5 (2)
C2—C1—C6—C5	−1.3 (4)	C9—O5—C10—C12	−82.6 (3)
S1—C1—C6—C5	176.86 (19)	C9—O5—C10—C11	155.5 (2)
C2—C1—C6—C7	−179.3 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8B···O3ⁱ	0.99	2.27	3.236 (3)	166
C10—H10···O3ⁱⁱ	1.00	2.42	3.245 (3)	140

Symmetry codes: (i) −x+3/2, y+1/2, −z+3/2; (ii) x+1, y, z.

Experimental details

Crystal data
Chemical formula	C₁₂H₁₃NO₅S
M_r	283.29
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	173
a, b, c (Å)	8.0922 (3), 9.2314 (4), 17.7414 (8)
β (°)	100.075 (2)
V (Å³)	1304.89 (9)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.26
Crystal size (mm)	0.14 × 0.12 × 0.06

Data collection
Diffractometer	Nonius KappaCCD diffractometer
Absorption correction	Multi-scan (SORTAV; Blessing, 1997)
T_min, T_max	0.964, 0.984
No. of measured, independent and observed [I > 2σ(I)] reflections	5518, 2953, 2339
R_int	0.041
(sin θ/λ)_max (Å⁻¹)	0.648

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.055, 0.119, 1.11
No. of reflections	2953
No. of parameters	174
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.41, −0.43

Computer programs: COLLECT (Hooft, 1998), DENZO (Otwinowski & Minor, 1997), SCALEPACK (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8B···O3ⁱ	0.99	2.27	3.236 (3)	165.7
C10—H10···O3ⁱⁱ	1.00	2.42	3.245 (3)	139.8

Symmetry codes: (i) −x+3/2, y+1/2, −z+3/2; (ii) x+1, y, z.

Acknowledgements

The authors are grateful to the Higher Education Commission of Pakistan and PCSIR for the support to carry out this work.

References

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