Methyl 2-ethyl-4-hydr­oxy-2H-1,2-benzo­thia­zine-3-carboxyl­ate 1,1-dioxide

Arshad, M.N.; Zia-ur-Rehman, M.; Khan, I.U.

doi:10.1107/S1600536810012365

organic compounds

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ISSN: 2056-9890

Volume 66| Part 5| May 2010| Page o1070

https://doi.org/10.1107/S1600536810012365

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Methyl 2-ethyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide

Muhammad Nadeem Arshad,^a ‡ Muhammad Zia-ur-Rehman ^b and Islam Ullah Khan ^a ^*

^aMaterials Chemistry Laboratory, Department of Chemistry, GC University, Lahore, Pakistan, and ^bApplied Chemistry Research Centre, PCSIR Laboratories Complex, Lahore 54600, Pakistan
^*Correspondence e-mail: iukhan.gcu@gmail.com

(Received 31 March 2010; accepted 1 April 2010; online 14 April 2010)

In the title compound, C₁₂H₁₃NO₅S, the thiazine ring adopts a half chair conformation and an intramolecular O—H⋯O hydrogen bond generates an S(6) ring. In the crystal, the molecules are linked by C—H⋯O interactions, leading to zigzag chains along the b axis.

Related literature

For background to the biological properties of thiazines, see: Zia-ur-Rehman et al. (2005 , 2006 ). For related structures, see: Arshad et al. (2009a ,b ). For graph-set notation, see: Bernstein, et al. (1995 ).

Experimental

Crystal data

C₁₂H₁₃NO₅S
M_r = 283.29
Orthorhombic, P n a 2₁
a = 7.2460 (6) Å
b = 20.548 (2) Å
c = 8.5710 (8) Å
V = 1276.1 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.27 mm⁻¹
T = 296 K
0.24 × 0.14 × 0.10 mm

Data collection

Bruker KAPPA APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2007 ) T_min = 0.938, T_max = 0.974
14253 measured reflections
3148 independent reflections
1270 reflections with I > 2σ(I)
R_int = 0.133

Refinement

R[F² > 2σ(F²)] = 0.054
wR(F²) = 0.102
S = 0.95
3148 reflections
176 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.22 e Å⁻³
Δρ_min = −0.25 e Å⁻³
Absolute structure: Flack (1983 ), 1464 Friedel pairs
Flack parameter: 0.07 (12)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3⋯O4	0.82	1.92	2.628 (5)	144
C4—H4⋯O4ⁱ	0.93	2.55	3.395 (5)	152
C10—H10B⋯O2ⁱⁱ	0.96	2.52	3.320 (5)	141
Symmetry codes: (i) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z+1]$ ; (ii) $[-x+1, -y, z-{\script{1\over 2}}]$ .

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: ORTEP-3 (Farrugia, 1997 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: X-SEED (Barbur, 2001 ); WinGX (Farrugia, 1999 ) and PLATON.

Supporting information

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: https://doi.org/10.1107/S1600536810012365/hb5390sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810012365/hb5390Isup2.hkl

checkCIF report

Comment top

Under the heading of synthesis and X-ray studies and biological evaluation of thiazine related heterocycles our group has already reported biological applications (Zia-ur-Rehman et al., 2005, 2006) and the crystal structures of 1,2-benzothiazine derivatives (Arshad et al., 2009a,b) II & III. The title compound Methyl 2-ethyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide (I) is different only in H-alkylation. The hydrogen bonding interactions in I, II and III are pretty much common. The intramolecular O–H···O interaction tend to rise the six membered ring motif R₁¹(6) (Bernstein, et al., 1995) which is almost planar with the r.m.s deviaton of 0.0156Å and iclined at dihedral angle of 25.1 (6)° & 17.5 (6)° with respect to the thiazine and benzene ring respectively. The half chair shaped thiazine ring exihibits a maximum deviation from the least square plane measure 0.347 (2)Å for S1 and 0.345 (2)Å for C1. The intermoleculear C–H···O hydrogen bonding forms zig-zag network along the b axes. The bond lngths and bond angles are compareable with the molecules II and III.

Related literature top

For background to the biological properties of thiazines, see: Zia-ur-Rehman et al. (2005, 2006). For related structures, see: Arshad et al. (2009a,b). For graph-set notation, see: Bernstein, et al. (1995).

Experimental top

Ethyl iodide (250 mg, 1.6 mmol) was added drop wise to the mixture of methyl 4-hydroxy-2H-1,2-benzothiazine-3-carboxylate-1,1-dioxide (350 mg, 1.37 mmol), anhydrous potassium carbonate (161 mg, 1.6 mmol) and dimethylformamide (5 ml) in a round bottom flask. Contents were stirred at room temperature for 5 h under nitrogen atmosphere and poured over ice cooled water (100 ml) resulting white precipetates, which was filtered and washed with cold water. Colourless needles of (I) were obtained by re-crystallization from a methanol solution under slow evaporation.

Structure description top

For background to the biological properties of thiazines, see: Zia-ur-Rehman et al. (2005, 2006). For related structures, see: Arshad et al. (2009a,b). For graph-set notation, see: Bernstein, et al. (1995).

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: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: X-SEED (Barbur, 2001); WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of (I) showing 50% displacement ellipsoids.
	Fig. 2. Unit cell packing for (I) showing the inter and intramolecular hydrogen bondings using dashed lines. Hydrogen atoms have been omitted for clarity.

Methyl 2-ethyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide top

Crystal data top

C₁₂H₁₃NO₅S	F(000) = 592
M_r = 283.29	D_x = 1.475 Mg m⁻³
Orthorhombic, Pna2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2n	Cell parameters from 733 reflections
a = 7.2460 (6) Å	θ = 2.6–17.3°
b = 20.548 (2) Å	µ = 0.27 mm⁻¹
c = 8.5710 (8) Å	T = 296 K
V = 1276.1 (2) Å³	Cut needle, colourless
Z = 4	0.24 × 0.14 × 0.10 mm

Data collection top

Bruker KAPPA APEXII CCD diffractometer	3148 independent reflections
Radiation source: fine-focus sealed tube	1270 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.133
φ and ω scans	θ_max = 28.3°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −9→9
T_min = 0.938, T_max = 0.974	k = −26→27
14253 measured reflections	l = −11→11

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.054	w = 1/[σ²(F_o²) + (0.0219P)²] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.102	(Δ/σ)_max < 0.001
S = 0.95	Δρ_max = 0.22 e Å⁻³
3148 reflections	Δρ_min = −0.25 e Å⁻³
176 parameters	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
1 restraint	Extinction coefficient: 0.0062 (9)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 1464 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.07 (12)

Crystal data top

C₁₂H₁₃NO₅S	V = 1276.1 (2) Å³
M_r = 283.29	Z = 4
Orthorhombic, Pna2₁	Mo Kα radiation
a = 7.2460 (6) Å	µ = 0.27 mm⁻¹
b = 20.548 (2) Å	T = 296 K
c = 8.5710 (8) Å	0.24 × 0.14 × 0.10 mm

Data collection top

Bruker KAPPA APEXII CCD diffractometer	3148 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2007)	1270 reflections with I > 2σ(I)
T_min = 0.938, T_max = 0.974	R_int = 0.133
14253 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.054	H-atom parameters constrained
wR(F²) = 0.102	Δρ_max = 0.22 e Å⁻³
S = 0.95	Δρ_min = −0.25 e Å⁻³
3148 reflections	Absolute structure: Flack (1983), 1464 Friedel pairs
176 parameters	Absolute structure parameter: 0.07 (12)
1 restraint

Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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	0.19292 (16)	0.06952 (6)	0.49242 (15)	0.0514 (4)
O1	0.0578 (4)	0.10023 (16)	0.3936 (4)	0.0648 (10)
O2	0.1809 (4)	0.00107 (13)	0.5198 (4)	0.0716 (10)
O3	0.3931 (4)	0.26033 (12)	0.5272 (4)	0.0532 (8)
H3	0.4444	0.2709	0.4458	0.080*
O4	0.5638 (4)	0.23848 (15)	0.2618 (4)	0.0563 (10)
O5	0.5818 (4)	0.13380 (14)	0.1843 (4)	0.0550 (9)
N1	0.3974 (4)	0.08716 (17)	0.4241 (4)	0.0413 (9)
C1	0.1976 (6)	0.1103 (2)	0.6695 (5)	0.0422 (11)
C2	0.1285 (6)	0.0824 (2)	0.8054 (6)	0.0536 (14)
H2	0.0732	0.0416	0.8027	0.064*
C3	0.1429 (6)	0.1160 (3)	0.9446 (6)	0.0560 (15)
H3A	0.1030	0.0970	1.0370	0.067*
C4	0.2163 (6)	0.1776 (2)	0.9459 (5)	0.0589 (15)
H4	0.2201	0.2009	1.0389	0.071*
C5	0.2849 (6)	0.2056 (2)	0.8105 (6)	0.0560 (14)
H5	0.3341	0.2474	0.8139	0.067*
C6	0.2811 (6)	0.1722 (2)	0.6708 (6)	0.0396 (11)
C7	0.3701 (5)	0.1955 (2)	0.5296 (6)	0.0406 (11)
C8	0.4294 (6)	0.1557 (2)	0.4160 (5)	0.0372 (11)
C9	0.5296 (6)	0.1805 (3)	0.2822 (5)	0.0471 (12)
C10	0.6951 (6)	0.1538 (2)	0.0543 (5)	0.0707 (16)
H10A	0.6288	0.1848	−0.0079	0.106*
H10B	0.7252	0.1165	−0.0083	0.106*
H10C	0.8066	0.1733	0.0926	0.106*
C11	0.5572 (6)	0.0441 (2)	0.4634 (5)	0.0548 (15)
H11A	0.6478	0.0475	0.3805	0.066*
H11B	0.5143	−0.0006	0.4657	0.066*
C12	0.6504 (6)	0.0588 (3)	0.6154 (7)	0.0840 (19)
H12A	0.6928	0.1031	0.6152	0.126*
H12B	0.7537	0.0301	0.6290	0.126*
H12C	0.5646	0.0527	0.6994	0.126*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0554 (7)	0.0474 (7)	0.0516 (7)	−0.0144 (7)	0.0019 (9)	−0.0055 (8)
O1	0.051 (2)	0.083 (3)	0.060 (2)	−0.0095 (18)	−0.010 (2)	−0.003 (2)
O2	0.097 (2)	0.0399 (19)	0.078 (3)	−0.0283 (16)	0.014 (2)	−0.010 (2)
O3	0.065 (2)	0.033 (2)	0.061 (3)	−0.0045 (14)	0.0097 (19)	0.0007 (19)
O4	0.067 (2)	0.042 (2)	0.059 (2)	−0.0064 (17)	0.0121 (19)	0.0070 (18)
O5	0.068 (2)	0.048 (2)	0.050 (2)	0.0000 (17)	0.0208 (19)	−0.0001 (19)
N1	0.044 (2)	0.037 (2)	0.043 (2)	−0.0036 (17)	0.0052 (18)	−0.0020 (18)
C1	0.038 (3)	0.048 (3)	0.040 (3)	0.000 (2)	0.000 (2)	−0.006 (3)
C2	0.038 (3)	0.056 (4)	0.066 (4)	−0.003 (2)	0.009 (3)	0.005 (3)
C3	0.056 (3)	0.062 (4)	0.050 (4)	0.010 (3)	0.012 (3)	0.008 (3)
C4	0.062 (3)	0.075 (4)	0.039 (4)	0.017 (3)	0.006 (3)	−0.010 (3)
C5	0.061 (3)	0.051 (3)	0.056 (4)	0.002 (3)	0.003 (3)	−0.011 (3)
C6	0.039 (3)	0.035 (3)	0.045 (3)	0.002 (2)	−0.001 (3)	0.000 (3)
C7	0.044 (3)	0.033 (3)	0.045 (3)	−0.005 (2)	−0.003 (2)	−0.001 (3)
C8	0.040 (3)	0.027 (3)	0.045 (3)	−0.004 (2)	−0.005 (2)	0.002 (2)
C9	0.043 (3)	0.058 (3)	0.040 (3)	−0.003 (3)	−0.006 (3)	−0.001 (3)
C10	0.086 (4)	0.065 (4)	0.061 (4)	−0.004 (3)	0.036 (3)	0.002 (3)
C11	0.057 (3)	0.037 (3)	0.070 (4)	0.010 (2)	0.005 (3)	0.010 (3)
C12	0.069 (4)	0.102 (5)	0.081 (5)	0.019 (3)	−0.013 (3)	0.015 (4)

Geometric parameters (Å, º) top

S1—O2	1.429 (3)	C4—C5	1.388 (6)
S1—O1	1.441 (3)	C4—H4	0.9300
S1—N1	1.634 (3)	C5—C6	1.381 (6)
S1—C1	1.734 (5)	C5—H5	0.9300
O3—C7	1.343 (4)	C6—C7	1.452 (6)
O3—H3	0.8200	C7—C8	1.343 (5)
O4—C9	1.229 (5)	C8—C9	1.450 (6)
O5—C9	1.330 (5)	C10—H10A	0.9600
O5—C10	1.444 (5)	C10—H10B	0.9600
N1—C8	1.428 (5)	C10—H10C	0.9600
N1—C11	1.495 (5)	C11—C12	1.499 (6)
C1—C2	1.392 (6)	C11—H11A	0.9700
C1—C6	1.408 (5)	C11—H11B	0.9700
C2—C3	1.383 (6)	C12—H12A	0.9600
C2—H2	0.9300	C12—H12B	0.9600
C3—C4	1.372 (6)	C12—H12C	0.9600
C3—H3A	0.9300

O2—S1—O1	119.1 (2)	C1—C6—C7	118.8 (4)
O2—S1—N1	109.44 (18)	C8—C7—O3	123.6 (4)
O1—S1—N1	107.97 (19)	C8—C7—C6	123.0 (4)
O2—S1—C1	109.4 (2)	O3—C7—C6	113.3 (4)
O1—S1—C1	108.4 (2)	C7—C8—N1	120.9 (4)
N1—S1—C1	100.9 (2)	C7—C8—C9	121.3 (4)
C7—O3—H3	109.5	N1—C8—C9	117.9 (4)
C9—O5—C10	116.3 (3)	O4—C9—O5	123.6 (4)
C8—N1—C11	117.9 (3)	O4—C9—C8	123.7 (4)
C8—N1—S1	112.5 (3)	O5—C9—C8	112.7 (4)
C11—N1—S1	119.4 (3)	O5—C10—H10A	109.5
C2—C1—C6	121.3 (4)	O5—C10—H10B	109.5
C2—C1—S1	121.8 (4)	H10A—C10—H10B	109.5
C6—C1—S1	116.9 (4)	O5—C10—H10C	109.5
C3—C2—C1	119.3 (4)	H10A—C10—H10C	109.5
C3—C2—H2	120.4	H10B—C10—H10C	109.5
C1—C2—H2	120.4	N1—C11—C12	115.2 (4)
C4—C3—C2	119.8 (5)	N1—C11—H11A	108.5
C4—C3—H3A	120.1	C12—C11—H11A	108.5
C2—C3—H3A	120.1	N1—C11—H11B	108.5
C3—C4—C5	120.9 (4)	C12—C11—H11B	108.5
C3—C4—H4	119.5	H11A—C11—H11B	107.5
C5—C4—H4	119.5	C11—C12—H12A	109.5
C6—C5—C4	120.8 (4)	C11—C12—H12B	109.5
C6—C5—H5	119.6	H12A—C12—H12B	109.5
C4—C5—H5	119.6	C11—C12—H12C	109.5
C5—C6—C1	117.7 (4)	H12A—C12—H12C	109.5
C5—C6—C7	123.3 (4)	H12B—C12—H12C	109.5

O2—S1—N1—C8	−171.2 (3)	S1—C1—C6—C7	−4.9 (5)
O1—S1—N1—C8	57.8 (3)	C5—C6—C7—C8	153.4 (4)
C1—S1—N1—C8	−55.9 (3)	C1—C6—C7—C8	−21.9 (6)
O2—S1—N1—C11	−26.6 (4)	C5—C6—C7—O3	−24.2 (6)
O1—S1—N1—C11	−157.6 (3)	C1—C6—C7—O3	160.5 (4)
C1—S1—N1—C11	88.7 (3)	O3—C7—C8—N1	−178.8 (4)
O2—S1—C1—C2	−22.5 (4)	C6—C7—C8—N1	3.8 (6)
O1—S1—C1—C2	108.9 (4)	O3—C7—C8—C9	2.0 (6)
N1—S1—C1—C2	−137.8 (4)	C6—C7—C8—C9	−175.4 (4)
O2—S1—C1—C6	155.2 (3)	C11—N1—C8—C7	−105.7 (4)
O1—S1—C1—C6	−73.4 (4)	S1—N1—C8—C7	39.5 (5)
N1—S1—C1—C6	39.9 (4)	C11—N1—C8—C9	73.6 (5)
C6—C1—C2—C3	−0.3 (7)	S1—N1—C8—C9	−141.2 (3)
S1—C1—C2—C3	177.3 (3)	C10—O5—C9—O4	4.3 (7)
C1—C2—C3—C4	3.3 (7)	C10—O5—C9—C8	−175.3 (4)
C2—C3—C4—C5	−3.2 (7)	C7—C8—C9—O4	−1.5 (7)
C3—C4—C5—C6	0.0 (7)	N1—C8—C9—O4	179.3 (4)
C4—C5—C6—C1	2.9 (6)	C7—C8—C9—O5	178.1 (4)
C4—C5—C6—C7	−172.4 (4)	N1—C8—C9—O5	−1.1 (5)
C2—C1—C6—C5	−2.8 (6)	C8—N1—C11—C12	57.6 (5)
S1—C1—C6—C5	179.5 (3)	S1—N1—C11—C12	−85.1 (4)
C2—C1—C6—C7	172.8 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O4	0.82	1.92	2.628 (5)	144
C4—H4···O4ⁱ	0.93	2.55	3.395 (5)	152
C10—H10B···O2ⁱⁱ	0.96	2.52	3.320 (5)	141

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

Experimental details

Crystal data
Chemical formula	C₁₂H₁₃NO₅S
M_r	283.29
Crystal system, space group	Orthorhombic, Pna2₁
Temperature (K)	296
a, b, c (Å)	7.2460 (6), 20.548 (2), 8.5710 (8)
V (Å³)	1276.1 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.27
Crystal size (mm)	0.24 × 0.14 × 0.10

Data collection
Diffractometer	Bruker KAPPA APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2007)
T_min, T_max	0.938, 0.974
No. of measured, independent and observed [I > 2σ(I)] reflections	14253, 3148, 1270
R_int	0.133
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.054, 0.102, 0.95
No. of reflections	3148
No. of parameters	176
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.25
Absolute structure	Flack (1983), 1464 Friedel pairs
Absolute structure parameter	0.07 (12)

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009), X-SEED (Barbur, 2001); WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O4	0.82	1.92	2.628 (5)	144
C4—H4···O4ⁱ	0.93	2.55	3.395 (5)	152
C10—H10B···O2ⁱⁱ	0.96	2.52	3.320 (5)	141

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

Footnotes

‡Current address: Department of Chemistry, Georgetown University, 37th and O St NW, Washington DC 20057-212 USA.

Acknowledgements

The authors acknowledge the Higher Education Commission (HEC) of Pakistan for providing a grant under the project `Strengthening the Materials Chemistry Laboratory at GC University, Lahore'. MNA also acknowledges the HEC for providing a fellowship under the International Research Support Initiative Program (IRSIP)

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