2-{[2-(1-Methyl-2,2-dioxo-3,4-dihydro-1H-2λ6,1-benzothia­zin-4-yl­idene)hydrazin-1-yl­idene]meth­yl}phenol

Shafiq, M.; Harrison, W.T.A.; Khan, I.U.; Bukhari, I.H.; Bokhari, T.H.

doi:10.1107/S1600536812034101

organic compounds

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ISSN: 2056-9890

Volume 68| Part 9| September 2012| Page o2643

doi:10.1107/S1600536812034101

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2-{[2-(1-Methyl-2,2-dioxo-3,4-dihydro-1H-2λ⁶,1-benzothiazin-4-ylidene)hydrazin-1-ylidene]methyl}phenol

Muhammad Shafiq,^a ^* William T. A. Harrison,^b Islam Ullah Khan,^c Iftikhar Hussain Bukhari ^a and Tanveer Hussain Bokhari ^a

^aDepartment of Chemistry, Government College University, Faisalabad 38000, Pakistan, ^bDepartment of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, Scotland, and ^cMaterials Chemistry Laboratory, Department of Chemistry, Government College University, Lahore, Pakistan
^*Correspondence e-mail: hafizshafique@hotmail.com

(Received 28 July 2012; accepted 31 July 2012; online 4 August 2012)

In the title compound, C₁₆H₁₅N₃O₃S, the dihedral angle between the aromatic rings is 8.18 (11)° and the C=N—N=C torsion angle is 178.59 (14)°. The conformation of the thiazine ring is an envelope, with the S atom displaced by 0.8157 (18) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.045 Å). An intramolecular O—H⋯N hydrogen bond closes an S(6) ring. In the crystal, weak C—H⋯O interactions link the molecules, with all three O atoms acting as acceptors.

Related literature

For the synthesis and biological activity of the title compound and related materials, see: Shafiq et al. (2011 ).

Experimental

Crystal data

C₁₆H₁₅N₃O₃S
M_r = 329.37
Monoclinic, P 2₁ /n
a = 6.5530 (2) Å
b = 15.8719 (5) Å
c = 14.5804 (4) Å
β = 91.147 (1)°
V = 1516.18 (8) Å³
Z = 4
Mo Kα radiation
μ = 0.23 mm⁻¹
T = 296 K
0.40 × 0.05 × 0.05 mm

Data collection

Bruker APEXII CCD diffractometer
14391 measured reflections
3778 independent reflections
3019 reflections with I > 2σ(I)
R_int = 0.020

Refinement

R[F² > 2σ(F²)] = 0.039
wR(F²) = 0.114
S = 1.03
3778 reflections
212 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.32 e Å⁻³
Δρ_min = −0.28 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3⋯N3	0.85 (2)	1.89 (2)	2.6574 (18)	151 (2)
C1—H1B⋯O3ⁱ	0.96	2.59	3.534 (3)	166
C3—H3A⋯O1ⁱⁱ	0.93	2.60	3.396 (2)	144
C9—H9A⋯O2ⁱ	0.97	2.44	3.138 (2)	129
C16—H16⋯O1ⁱⁱⁱ	0.93	2.60	3.440 (2)	151
Symmetry codes: (i) -x, -y+1, -z+1; (ii) x+1, y, z; (iii) $[x-{\script{1\over 2}}, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: ORTEP-3 (Farrugia, 1997 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812034101/bt5989sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812034101/bt5989Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812034101/bt5989Isup3.cml

checkCIF report

Related literature top

For the synthesis and biological activity of the title compound and related materials, see: Shafiq et al. (2011).

Experimental top

In the synthesis of title compound, 4-hydrazinylidene-1- methyl-3H-2λ⁶,1-benzothiazine-2,2-dione was subjected to react with 2-hydroxy benzaldehyde according to literature procedure ((Shafiq et al. (2011)). The product obtained was then recrystallized in ethylacetate under slow evaporation to obtain single crystals suitable for X-ray diffraction.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: ORTEP-3 (Farrugia, 1997).

Figures top

Fig. 1. The molecular structure of (I), showing displacement ellipsoids at the 50% probability level. The hydrogen bond is shown as a double-dashed line.

2-{[2-(1-Methyl-2,2-dioxo-3,4-dihydro-1H-2λ⁶,1-benzothiazin- 4-ylidene)hydrazin-1-ylidene]methyl}phenol top

Crystal data top

C₁₆H₁₅N₃O₃S	F(000) = 688
M_r = 329.37	D_x = 1.443 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 6831 reflections
a = 6.5530 (2) Å	θ = 2.8–28.2°
b = 15.8719 (5) Å	µ = 0.23 mm⁻¹
c = 14.5804 (4) Å	T = 296 K
β = 91.147 (1)°	Needle, yellow
V = 1516.18 (8) Å³	0.40 × 0.05 × 0.05 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	3019 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.020
Graphite monochromator	θ_max = 28.4°, θ_min = 2.6°
ϕ and ω scans	h = −8→8
14391 measured reflections	k = −21→20
3778 independent reflections	l = −19→19

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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.114	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ²(F_o²) + (0.0577P)² + 0.5143P] where P = (F_o² + 2F_c²)/3
3778 reflections	(Δ/σ)_max = 0.001
212 parameters	Δρ_max = 0.32 e Å⁻³
0 restraints	Δρ_min = −0.28 e Å⁻³

Crystal data top

C₁₆H₁₅N₃O₃S	V = 1516.18 (8) Å³
M_r = 329.37	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 6.5530 (2) Å	µ = 0.23 mm⁻¹
b = 15.8719 (5) Å	T = 296 K
c = 14.5804 (4) Å	0.40 × 0.05 × 0.05 mm
β = 91.147 (1)°

Data collection top

Bruker APEXII CCD diffractometer	3019 reflections with I > 2σ(I)
14391 measured reflections	R_int = 0.020
3778 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.039	0 restraints
wR(F²) = 0.114	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.32 e Å⁻³
3778 reflections	Δρ_min = −0.28 e Å⁻³
212 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
C1	0.5578 (3)	0.63906 (15)	0.45564 (14)	0.0583 (5)
H1A	0.5592	0.6923	0.4245	0.087*
H1B	0.5077	0.5963	0.4144	0.087*
H1C	0.6939	0.6250	0.4760	0.087*
C2	0.4661 (2)	0.70248 (9)	0.60704 (10)	0.0323 (3)
C3	0.6391 (2)	0.75336 (11)	0.60255 (12)	0.0418 (4)
H3A	0.7228	0.7498	0.5519	0.050*
C4	0.6875 (3)	0.80886 (11)	0.67218 (12)	0.0453 (4)
H4	0.8039	0.8420	0.6683	0.054*
C5	0.5651 (3)	0.81578 (11)	0.74765 (12)	0.0436 (4)
H5	0.5973	0.8538	0.7942	0.052*
C6	0.3944 (2)	0.76554 (10)	0.75302 (11)	0.0384 (3)
H6	0.3127	0.7699	0.8042	0.046*
C7	0.3401 (2)	0.70828 (9)	0.68407 (10)	0.0318 (3)
C8	0.1578 (2)	0.65501 (9)	0.69491 (10)	0.0323 (3)
C9	0.1241 (3)	0.58446 (12)	0.62738 (11)	0.0470 (4)
H9A	−0.0177	0.5670	0.6280	0.056*
H9B	0.2080	0.5366	0.6450	0.056*
C10	−0.2398 (2)	0.63187 (10)	0.83713 (11)	0.0375 (3)
H10	−0.2025	0.6761	0.8758	0.045*
C11	−0.4218 (2)	0.58389 (10)	0.85695 (10)	0.0357 (3)
C12	−0.4875 (2)	0.51625 (10)	0.80224 (11)	0.0383 (3)
C13	−0.6624 (3)	0.47198 (12)	0.82474 (13)	0.0490 (4)
H13	−0.7045	0.4263	0.7891	0.059*
C14	−0.7732 (3)	0.49541 (13)	0.89940 (15)	0.0566 (5)
H14	−0.8905	0.4657	0.9138	0.068*
C15	−0.7125 (3)	0.56253 (13)	0.95334 (14)	0.0584 (5)
H15	−0.7889	0.5782	1.0036	0.070*
C16	−0.5388 (3)	0.60604 (12)	0.93243 (12)	0.0474 (4)
H16	−0.4979	0.6511	0.9691	0.057*
S1	0.18651 (6)	0.61737 (3)	0.51673 (2)	0.03890 (13)
N1	0.42477 (18)	0.64443 (9)	0.53490 (9)	0.0382 (3)
N2	0.03875 (19)	0.67010 (8)	0.76209 (9)	0.0378 (3)
N3	−0.12812 (19)	0.61537 (8)	0.76789 (9)	0.0374 (3)
O1	0.06395 (19)	0.68861 (10)	0.49308 (9)	0.0581 (4)
O2	0.1846 (2)	0.54798 (10)	0.45479 (9)	0.0610 (4)
O3	−0.3885 (2)	0.49217 (9)	0.72635 (9)	0.0557 (4)
H3	−0.285 (4)	0.5240 (15)	0.7235 (16)	0.067*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0359 (8)	0.0874 (14)	0.0524 (11)	−0.0090 (9)	0.0175 (7)	−0.0246 (10)
C2	0.0275 (6)	0.0353 (7)	0.0342 (7)	−0.0008 (5)	0.0019 (5)	0.0000 (6)
C3	0.0329 (7)	0.0478 (9)	0.0448 (9)	−0.0081 (6)	0.0076 (6)	−0.0008 (7)
C4	0.0379 (8)	0.0441 (9)	0.0537 (10)	−0.0121 (7)	0.0005 (7)	0.0002 (8)
C5	0.0475 (9)	0.0395 (8)	0.0437 (9)	−0.0083 (7)	−0.0031 (7)	−0.0046 (7)
C6	0.0411 (8)	0.0380 (8)	0.0363 (8)	−0.0042 (6)	0.0048 (6)	−0.0022 (6)
C7	0.0294 (6)	0.0327 (7)	0.0335 (7)	−0.0012 (5)	0.0025 (5)	0.0028 (6)
C8	0.0323 (7)	0.0351 (7)	0.0297 (7)	−0.0033 (6)	0.0024 (5)	0.0026 (6)
C9	0.0585 (10)	0.0508 (10)	0.0323 (8)	−0.0227 (8)	0.0126 (7)	−0.0050 (7)
C10	0.0363 (7)	0.0381 (8)	0.0383 (8)	−0.0018 (6)	0.0072 (6)	0.0000 (6)
C11	0.0341 (7)	0.0371 (8)	0.0362 (7)	0.0011 (6)	0.0087 (6)	0.0045 (6)
C12	0.0389 (8)	0.0383 (8)	0.0381 (8)	0.0004 (6)	0.0059 (6)	0.0039 (6)
C13	0.0463 (9)	0.0464 (9)	0.0543 (10)	−0.0108 (8)	0.0046 (8)	0.0018 (8)
C14	0.0418 (9)	0.0618 (12)	0.0668 (12)	−0.0125 (8)	0.0164 (8)	0.0091 (10)
C15	0.0516 (10)	0.0650 (12)	0.0598 (11)	−0.0021 (9)	0.0295 (9)	0.0004 (10)
C16	0.0485 (9)	0.0491 (10)	0.0453 (9)	−0.0028 (8)	0.0171 (7)	−0.0049 (7)
S1	0.03155 (19)	0.0558 (3)	0.0296 (2)	−0.01232 (16)	0.00564 (13)	−0.00418 (16)
N1	0.0279 (6)	0.0499 (8)	0.0371 (7)	−0.0062 (5)	0.0078 (5)	−0.0085 (6)
N2	0.0333 (6)	0.0401 (7)	0.0403 (7)	−0.0054 (5)	0.0083 (5)	−0.0013 (5)
N3	0.0331 (6)	0.0396 (7)	0.0397 (7)	−0.0053 (5)	0.0084 (5)	0.0011 (5)
O1	0.0377 (6)	0.0885 (10)	0.0479 (7)	0.0080 (6)	−0.0021 (5)	0.0094 (7)
O2	0.0638 (8)	0.0775 (9)	0.0423 (7)	−0.0335 (7)	0.0167 (6)	−0.0228 (6)
O3	0.0623 (8)	0.0551 (8)	0.0505 (7)	−0.0147 (6)	0.0214 (6)	−0.0147 (6)

Geometric parameters (Å, º) top

C1—N1	1.4641 (19)	C9—H9B	0.9700
C1—H1A	0.9600	C10—N3	1.286 (2)
C1—H1B	0.9600	C10—C11	1.449 (2)
C1—H1C	0.9600	C10—H10	0.9300
C2—C3	1.394 (2)	C11—C16	1.399 (2)
C2—C7	1.4104 (19)	C11—C12	1.400 (2)
C2—N1	1.4203 (19)	C12—O3	1.349 (2)
C3—C4	1.376 (2)	C12—C13	1.389 (2)
C3—H3A	0.9300	C13—C14	1.372 (3)
C4—C5	1.379 (2)	C13—H13	0.9300
C4—H4	0.9300	C14—C15	1.378 (3)
C5—C6	1.377 (2)	C14—H14	0.9300
C5—H5	0.9300	C15—C16	1.371 (3)
C6—C7	1.396 (2)	C15—H15	0.9300
C6—H6	0.9300	C16—H16	0.9300
C7—C8	1.4745 (19)	S1—O2	1.4242 (13)
C8—N2	1.2870 (19)	S1—O1	1.4252 (15)
C8—C9	1.504 (2)	S1—N1	1.6358 (13)
C9—S1	1.7519 (16)	N2—N3	1.4004 (17)
C9—H9A	0.9700	O3—H3	0.85 (2)

N1—C1—H1A	109.5	N3—C10—C11	122.22 (15)
N1—C1—H1B	109.5	N3—C10—H10	118.9
H1A—C1—H1B	109.5	C11—C10—H10	118.9
N1—C1—H1C	109.5	C16—C11—C12	118.29 (14)
H1A—C1—H1C	109.5	C16—C11—C10	119.41 (15)
H1B—C1—H1C	109.5	C12—C11—C10	122.30 (14)
C3—C2—C7	119.28 (14)	O3—C12—C13	117.56 (16)
C3—C2—N1	118.96 (13)	O3—C12—C11	122.50 (14)
C7—C2—N1	121.73 (13)	C13—C12—C11	119.93 (15)
C4—C3—C2	120.75 (15)	C14—C13—C12	120.17 (17)
C4—C3—H3A	119.6	C14—C13—H13	119.9
C2—C3—H3A	119.6	C12—C13—H13	119.9
C3—C4—C5	120.71 (15)	C13—C14—C15	120.74 (16)
C3—C4—H4	119.6	C13—C14—H14	119.6
C5—C4—H4	119.6	C15—C14—H14	119.6
C6—C5—C4	119.02 (15)	C16—C15—C14	119.59 (17)
C6—C5—H5	120.5	C16—C15—H15	120.2
C4—C5—H5	120.5	C14—C15—H15	120.2
C5—C6—C7	122.12 (15)	C15—C16—C11	121.26 (17)
C5—C6—H6	118.9	C15—C16—H16	119.4
C7—C6—H6	118.9	C11—C16—H16	119.4
C6—C7—C2	118.11 (13)	O2—S1—O1	117.53 (9)
C6—C7—C8	119.44 (13)	O2—S1—N1	107.57 (8)
C2—C7—C8	122.44 (13)	O1—S1—N1	111.25 (8)
N2—C8—C7	118.66 (13)	O2—S1—C9	110.74 (8)
N2—C8—C9	123.59 (13)	O1—S1—C9	108.58 (9)
C7—C8—C9	117.74 (13)	N1—S1—C9	99.72 (8)
C8—C9—S1	110.29 (11)	C2—N1—C1	120.96 (13)
C8—C9—H9A	109.6	C2—N1—S1	117.24 (10)
S1—C9—H9A	109.6	C1—N1—S1	116.01 (11)
C8—C9—H9B	109.6	C8—N2—N3	114.62 (13)
S1—C9—H9B	109.6	C10—N3—N2	112.24 (13)
H9A—C9—H9B	108.1	C12—O3—H3	105.7 (16)

C7—C2—C3—C4	0.0 (2)	C11—C12—C13—C14	1.3 (3)
N1—C2—C3—C4	−178.31 (15)	C12—C13—C14—C15	−0.4 (3)
C2—C3—C4—C5	−0.5 (3)	C13—C14—C15—C16	−0.4 (3)
C3—C4—C5—C6	0.8 (3)	C14—C15—C16—C11	0.3 (3)
C4—C5—C6—C7	−0.6 (3)	C12—C11—C16—C15	0.6 (3)
C5—C6—C7—C2	0.1 (2)	C10—C11—C16—C15	179.69 (18)
C5—C6—C7—C8	178.70 (15)	C8—C9—S1—O2	171.30 (12)
C3—C2—C7—C6	0.2 (2)	C8—C9—S1—O1	−58.26 (15)
N1—C2—C7—C6	178.42 (14)	C8—C9—S1—N1	58.19 (14)
C3—C2—C7—C8	−178.33 (14)	C3—C2—N1—C1	−1.5 (2)
N1—C2—C7—C8	−0.1 (2)	C7—C2—N1—C1	−179.75 (16)
C6—C7—C8—N2	8.8 (2)	C3—C2—N1—S1	−153.63 (13)
C2—C7—C8—N2	−172.73 (14)	C7—C2—N1—S1	28.14 (19)
C6—C7—C8—C9	−169.98 (15)	O2—S1—N1—C2	−169.05 (12)
C2—C7—C8—C9	8.5 (2)	O1—S1—N1—C2	60.90 (13)
N2—C8—C9—S1	141.30 (14)	C9—S1—N1—C2	−53.51 (14)
C7—C8—C9—S1	−40.03 (19)	O2—S1—N1—C1	37.45 (16)
N3—C10—C11—C16	−178.83 (16)	O1—S1—N1—C1	−92.59 (15)
N3—C10—C11—C12	0.2 (2)	C9—S1—N1—C1	152.99 (15)
C16—C11—C12—O3	177.69 (16)	C7—C8—N2—N3	−178.86 (12)
C10—C11—C12—O3	−1.4 (2)	C9—C8—N2—N3	−0.2 (2)
C16—C11—C12—C13	−1.4 (2)	C11—C10—N3—N2	179.66 (14)
C10—C11—C12—C13	179.55 (15)	C8—N2—N3—C10	178.59 (14)
O3—C12—C13—C14	−177.81 (18)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···N3	0.85 (2)	1.89 (2)	2.6574 (18)	151 (2)
C1—H1B···O3ⁱ	0.96	2.59	3.534 (3)	166
C3—H3A···O1ⁱⁱ	0.93	2.60	3.396 (2)	144
C9—H9A···O2ⁱ	0.97	2.44	3.138 (2)	129
C16—H16···O1ⁱⁱⁱ	0.93	2.60	3.440 (2)	151

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

Experimental details

Crystal data
Chemical formula	C₁₆H₁₅N₃O₃S
M_r	329.37
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	296
a, b, c (Å)	6.5530 (2), 15.8719 (5), 14.5804 (4)
β (°)	91.147 (1)
V (Å³)	1516.18 (8)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.23
Crystal size (mm)	0.40 × 0.05 × 0.05

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	14391, 3778, 3019
R_int	0.020
(sin θ/λ)_max (Å⁻¹)	0.669

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.039, 0.114, 1.03
No. of reflections	3778
No. of parameters	212
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.32, −0.28

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009), ORTEP-3 (Farrugia, 1997).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···N3	0.85 (2)	1.89 (2)	2.6574 (18)	151 (2)
C1—H1B···O3ⁱ	0.96	2.59	3.534 (3)	166
C3—H3A···O1ⁱⁱ	0.93	2.60	3.396 (2)	144
C9—H9A···O2ⁱ	0.97	2.44	3.138 (2)	129
C16—H16···O1ⁱⁱⁱ	0.93	2.60	3.440 (2)	151

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

Acknowledgements

MS acknowledges Higher Education commission of Pakistan for supporting PhD studies and the provision of a grant to strengthen the Materials Chemistry Laboratory at GC University Lahore, Pakistan.

References

Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Shafiq, M., Zia-Ur-Rehman, M., Khan, I. U., Arshad, M. N. & Khan, S. A. (2011). J. Chilean Chem. Soc. 56, 527–531. CSD CrossRef CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar

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