(E)-3,4-Dihydroxy­benzaldehyde 4-ethyl­thio­semicarbazone

Kayed, S.F.; Farina, Y.; Baba, I.; Simpson, J.

doi:10.1107/S1600536808009148

organic compounds

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ISSN: 2056-9890

Volume 64| Part 5| May 2008| Pages o824-o825

doi:10.1107/S1600536808009148

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(E)-3,4-Dihydroxybenzaldehyde 4-ethylthiosemicarbazone

Safa'a Fares Kayed,^a Yang Farina,^a Ibrahim Baba ^a and Jim Simpson ^b ^*

^aSchool of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia, and ^bDepartment of Chemistry, University of Otago, PO Box 56, Dunedin, New Zealand
^*Correspondence e-mail: jsimpson@alkali.otago.ac.nz

(Received 3 April 2008; accepted 4 April 2008; online 10 April 2008)

The title compound, C₁₀H₁₃N₃O₂S, was prepared by condensation of 3,4-dihydroxybenzaldehyde with 4-ethyl-3-thiosemicarbazide. The molecule adopts an E configuration with respect to the C=N bond. One of the OH substituents on the dihydroxybenzene ring is disordered over the two possible 3-positions on either side of the ordered 4-hydroxy group. The occupancy of the major disorder component refined to 0.633 (7). The molecule is essentially planar, with an r.m.s. deviation through all non-H atoms of 0.0862 Å. An intramolecular N—H⋯N hydrogen bond forms between the outer amine residue and the imine N atom, generating an S(5) ring motif and contributing to the planarity of the molecule. In the crystal structure, an extensive network of classical O—H⋯O, O—H⋯S and N—H⋯S hydrogen bonds and weak C—H⋯O and S⋯O [3.301 (3) Å] interactions link molecules into sheets running approximately parallel to the ab plane.

Related literature

For related structures, see: Swesi et al. (2006 ); Kovala-Demertzi et al. (2004 ); Jian & Li (2006 ). For reference structural data, see: Allen et al. (1987 ). For ring motifs, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₁₀H₁₃N₃O₂S
M_r = 239.29
Monoclinic, P 2₁ /c
a = 10.6549 (12) Å
b = 12.9020 (16) Å
c = 8.6375 (11) Å
β = 107.910 (4)°
V = 1129.9 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.28 mm⁻¹
T = 91 (2) K
0.44 × 0.11 × 0.09 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2006 ) T_min = 0.818, T_max = 0.975
12327 measured reflections
1998 independent reflections
1507 reflections with I > 2σ(I)
R_int = 0.040

Refinement

R[F² > 2σ(F²)] = 0.059
wR(F²) = 0.168
S = 1.05
1998 reflections
165 parameters
2 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 1.41 e Å⁻³
Δρ_min = −0.64 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3B⋯N1	0.88	2.23	2.626 (4)	107
O5—H5A⋯S1ⁱ	0.84	2.82	3.106 (9)	102
C2—H2⋯O5ⁱⁱ	0.95	2.65	3.335 (8)	129
N2—H2A⋯S1ⁱⁱⁱ	0.88	2.52	3.392 (4)	172
O4—H4⋯O4^iv	0.84	2.16	2.988 (5)	169
C9—H9A⋯O3^v	0.99	2.46	2.985 (5)	113
Symmetry codes: (i) $[-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) $[-x+2, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (iii) -x+1, -y, -z+1; (iv) -x+2, -y+1, -z; (v) $[x-1, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker 2006); cell refinement: APEX2 and SAINT (Bruker 2006); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ) and TITAN2000 (Hunter & Simpson, 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and TITAN2000; molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: SHELXL97, enCIFer (Allen et al., 2004 ) and PLATON (Spek, 2003 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808009148/hg2389sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808009148/hg2389Isup2.hkl

checkCIF report

Comment top

For example the structure of the related molecule 2,3-dihydroxybenzaldehyde thiosemicarbazone hemihydrate has been reported by Swesi et al. (2006) as have the structures of a phenylthiocarbazole with a single hydroxy-substituent on the benzylidene ring (Jian & Li, 2006) and of a palladium(II) complex of an ethylthiosemicarbonate ligand deprotonated at the phenolate ring (Kovala-Demertzi et al., 2004).

The molecule adopts an E configuration with respect to the C=N bond and bond distances and angles are normal (Allen et al., 1987). One of the OH substituents on the dihydroxy benzene ring is disordered over the two possible 3-positions (labelled O3 and O5) on either side of the ordered O4 hydroxo group. Occupancy of the O3 and H5 atoms of the major disorder component refines to 0.633 (7). The molecule is essentially planar with an r.m.s. deviation through all non-hydrogen atoms of 0.0862 Å. An intramolecular N3—H3B···N1 hydrogen bond forms between the outer amine residue and the imine N atom generating an S(5) ring motif (Bernstein et al., 1995) which contributes to the planarity of the molecule.

In the crystal structure N2—H2A···S1 hydrogen bonds, Table 1, generate centrosymmetric R²₂(8) rings. Other classical O—H···O and O—H···S hydrogen bonds combine with weak C—H···O and S1···O4ⁱ interactions (d(S1···O4) = 3.301 (3) Å; i = -1 + x, 1/2 - y, 1/2 + z) to form sheets running approximately parallel to the ac diagonal, Fig 2.

Related literature top

For related structures, see: Swesi et al. (2006); Kovala-Demertzi et al. (2004); Jian & Li (2006). For reference structural data, see: Allen et al. (1987). For ring motifs, see: Bernstein et al. (1995).

Experimental top

The title compound C₁₀H₁₃N₃O₂S was prepared by heating an ethanolic (35 ml) solution of 3,4-dihydroxybenzaldehyde (1.4 g, 10 mmol) and 4-ethyl-3-thiosemicarbazide (1.2 g, 10 mmol) under reflux for 1 h. The resulting product was isolated and recrystallized from ethanol to afford red block-shaped crystals in 71% yield (m.p. 464–467 K).

Computing details top

Data collection: APEX2 (Bruker 2006); cell refinement: APEX2 (Bruker 2006) and SAINT (Bruker 2006); data reduction: SAINT (Bruker 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008) and TITAN2000 (Hunter & Simpson, 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and TITAN2000 (Hunter & Simpson, 1999); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004) and PLATON (Spek, 2003).

Figures top

	Fig. 1. The structure of (I), with atom labels and 50% probability displacement ellipsoids for non-H atoms. The intramolecular N—H···N hydrogen bond is drawn as a dashed line. For clarity only the major disorder component of the disordered OH groups is shown.
	Fig. 2. Crystal packing of (I) viewed down the b axis with hydrogen bonds drawn as dashed lines.

(E)-3,4-Dihydroxybenzaldehyde 4-ethylthiosemicarbazone top

Crystal data top

C₁₀H₁₃N₃O₂S	F(000) = 504
M_r = 239.29	D_x = 1.407 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3071 reflections
a = 10.6549 (12) Å	θ = 2.6–25.0°
b = 12.9020 (16) Å	µ = 0.28 mm⁻¹
c = 8.6375 (11) Å	T = 91 K
β = 107.910 (4)°	Block, red
V = 1129.9 (2) Å³	0.44 × 0.11 × 0.09 mm
Z = 4

Data collection top

Bruker APEXII CCD area-detector diffractometer	1998 independent reflections
Radiation source: fine-focus sealed tube	1507 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.040
ω scans	θ_max = 25.1°, θ_min = 3.1°
Absorption correction: multi-scan (SADABS; Bruker, 2006)	h = −12→12
T_min = 0.818, T_max = 0.975	k = −15→15
12327 measured reflections	l = −10→8

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)] = 0.059	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.168	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ²(F_o²) + (0.0718P)² + 1.7231P] where P = (F_o² + 2F_c²)/3
1998 reflections	(Δ/σ)_max < 0.001
165 parameters	Δρ_max = 1.41 e Å⁻³
2 restraints	Δρ_min = −0.64 e Å⁻³

Crystal data top

C₁₀H₁₃N₃O₂S	V = 1129.9 (2) Å³
M_r = 239.29	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 10.6549 (12) Å	µ = 0.28 mm⁻¹
b = 12.9020 (16) Å	T = 91 K
c = 8.6375 (11) Å	0.44 × 0.11 × 0.09 mm
β = 107.910 (4)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	1998 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2006)	1507 reflections with I > 2σ(I)
T_min = 0.818, T_max = 0.975	R_int = 0.040
12327 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.059	2 restraints
wR(F²) = 0.168	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	Δρ_max = 1.41 e Å⁻³
1998 reflections	Δρ_min = −0.64 e Å⁻³
165 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	Occ. (<1)
C1	0.7990 (3)	0.2409 (2)	0.2636 (3)	0.0304 (7)
C2	0.9009 (3)	0.1922 (2)	0.2235 (3)	0.0342 (7)
H2	0.9097	0.1190	0.2323	0.041*
C3	0.9897 (3)	0.2493 (3)	0.1712 (4)	0.0382 (8)
H3	1.048 (11)	0.201 (8)	0.147 (17)	0.046*	0.367 (7)
O3	1.0884 (4)	0.2059 (4)	0.1330 (6)	0.0525 (14)	0.633 (7)
H3A	1.1301	0.2516	0.0999	0.079*	0.633 (7)
C5	0.8761 (3)	0.4051 (3)	0.1995 (4)	0.0394 (8)
H5	0.862 (11)	0.477 (2)	0.177 (13)	0.047*	0.633 (7)
O5	0.8733 (10)	0.5042 (5)	0.1953 (12)	0.045 (2)	0.367 (7)
H5A	0.8856	0.5248	0.1089	0.068*	0.367 (7)
C4	0.9776 (3)	0.3557 (3)	0.1580 (4)	0.0381 (8)
O4	1.0659 (2)	0.4115 (2)	0.1053 (3)	0.0503 (7)
H4	1.0294	0.4656	0.0584	0.075*
C6	0.7871 (3)	0.3484 (2)	0.2514 (3)	0.0334 (7)
H6	0.7178	0.3825	0.2787	0.040*
C7	0.7094 (3)	0.1775 (3)	0.3225 (3)	0.0357 (7)
H7	0.7228	0.1047	0.3322	0.043*
N1	0.6134 (2)	0.2175 (2)	0.3612 (3)	0.0390 (7)
N2	0.5403 (3)	0.1489 (3)	0.4216 (3)	0.0442 (7)
H2A	0.5567	0.0819	0.4244	0.053*
C8	0.4433 (3)	0.1862 (3)	0.4763 (4)	0.0458 (9)
S1	0.36442 (11)	0.10262 (10)	0.56744 (13)	0.0685 (4)
N3	0.4168 (3)	0.2853 (3)	0.4565 (3)	0.0506 (8)
H3B	0.4660	0.3233	0.4133	0.061*
C9	0.3112 (4)	0.3371 (4)	0.5010 (5)	0.0678 (13)
H9A	0.3118	0.3133	0.6102	0.081*
H9B	0.2252	0.3177	0.4224	0.081*
C10	0.3260 (5)	0.4506 (5)	0.5024 (6)	0.0804 (15)
H10A	0.4042	0.4708	0.5917	0.121*
H10B	0.2476	0.4831	0.5179	0.121*
H10C	0.3361	0.4735	0.3987	0.121*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0251 (14)	0.0466 (18)	0.0195 (14)	−0.0048 (12)	0.0069 (11)	0.0028 (12)
C2	0.0353 (16)	0.0376 (17)	0.0304 (15)	0.0009 (13)	0.0112 (13)	0.0039 (13)
C3	0.0292 (16)	0.057 (2)	0.0319 (16)	0.0021 (14)	0.0146 (13)	0.0001 (15)
O3	0.037 (3)	0.075 (3)	0.059 (3)	0.009 (2)	0.036 (2)	−0.002 (2)
C5	0.0427 (18)	0.0392 (18)	0.0365 (17)	−0.0057 (15)	0.0122 (14)	0.0051 (15)
O5	0.048 (4)	0.035 (4)	0.053 (5)	−0.010 (4)	0.015 (3)	0.013 (4)
C4	0.0331 (16)	0.056 (2)	0.0265 (15)	−0.0149 (15)	0.0113 (13)	0.0037 (14)
O4	0.0449 (14)	0.0657 (17)	0.0471 (14)	−0.0192 (12)	0.0241 (12)	0.0093 (12)
C6	0.0304 (15)	0.0422 (17)	0.0295 (16)	0.0020 (13)	0.0119 (13)	0.0009 (13)
C7	0.0348 (16)	0.0476 (19)	0.0252 (15)	−0.0110 (14)	0.0099 (13)	0.0018 (13)
N1	0.0281 (13)	0.0639 (18)	0.0267 (13)	−0.0131 (12)	0.0110 (11)	0.0059 (12)
N2	0.0380 (14)	0.0675 (19)	0.0319 (14)	−0.0205 (14)	0.0178 (12)	−0.0021 (13)
C8	0.0331 (17)	0.082 (3)	0.0250 (16)	−0.0237 (18)	0.0133 (13)	−0.0102 (17)
S1	0.0738 (7)	0.0931 (9)	0.0585 (7)	−0.0513 (6)	0.0497 (6)	−0.0299 (6)
N3	0.0305 (14)	0.092 (3)	0.0352 (15)	−0.0037 (15)	0.0181 (12)	0.0076 (16)
C9	0.038 (2)	0.131 (4)	0.039 (2)	0.008 (2)	0.0176 (16)	0.000 (2)
C10	0.076 (3)	0.122 (5)	0.053 (3)	0.036 (3)	0.034 (2)	0.000 (3)

Geometric parameters (Å, º) top

C1—C2	1.388 (4)	C7—N1	1.278 (4)
C1—C6	1.395 (5)	C7—H7	0.9500
C1—C7	1.462 (4)	N1—N2	1.384 (3)
C2—C3	1.380 (4)	N2—C8	1.350 (4)
C2—H2	0.9500	N2—H2A	0.8800
C3—O3	1.319 (5)	C8—N3	1.310 (5)
C3—C4	1.380 (5)	C8—S1	1.702 (3)
C3—H3	0.950 (10)	S1—O4ⁱ	3.301 (2)
O3—H3A	0.8400	N3—C9	1.457 (5)
C5—O5	1.279 (7)	N3—H3B	0.8800
C5—C6	1.376 (4)	C9—C10	1.473 (7)
C5—C4	1.394 (5)	C9—H9A	0.9900
C5—H5	0.950 (10)	C9—H9B	0.9900
O5—H5A	0.8400	C10—H10A	0.9800
C4—O4	1.369 (3)	C10—H10B	0.9800
O4—H4	0.8400	C10—H10C	0.9800
C6—H6	0.9500

C2—C1—C6	119.4 (3)	N1—C7—C1	121.7 (3)
C2—C1—C7	118.6 (3)	N1—C7—H7	119.1
C6—C1—C7	121.9 (3)	C1—C7—H7	119.1
C3—C2—C1	120.6 (3)	C7—N1—N2	115.4 (3)
C3—C2—H2	119.7	C8—N2—N1	119.0 (3)
C1—C2—H2	119.7	C8—N2—H2A	120.5
O3—C3—C4	117.6 (3)	N1—N2—H2A	120.5
O3—C3—C2	122.3 (4)	N3—C8—N2	117.4 (3)
C4—C3—C2	120.1 (3)	N3—C8—S1	124.2 (3)
C4—C3—H3	133 (8)	N2—C8—S1	118.4 (3)
C2—C3—H3	107 (8)	C8—N3—C9	124.5 (3)
C3—O3—H3A	109.5	C8—N3—H3B	117.8
O5—C5—C6	121.9 (5)	C9—N3—H3B	117.8
O5—C5—C4	117.6 (5)	N3—C9—C10	111.6 (4)
C6—C5—C4	120.5 (3)	N3—C9—H9A	109.3
C6—C5—H5	120 (7)	C10—C9—H9A	109.3
C4—C5—H5	119 (7)	N3—C9—H9B	109.3
C5—O5—H5A	109.5	C10—C9—H9B	109.3
O4—C4—C3	119.6 (3)	H9A—C9—H9B	108.0
O4—C4—C5	120.8 (3)	C9—C10—H10A	109.5
C3—C4—C5	119.6 (3)	C9—C10—H10B	109.5
C4—O4—H4	109.5	H10A—C10—H10B	109.5
C5—C6—C1	119.9 (3)	C9—C10—H10C	109.5
C5—C6—H6	120.1	H10A—C10—H10C	109.5
C1—C6—H6	120.1	H10B—C10—H10C	109.5

Symmetry code: (i) x−1, −y+1/2, z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3B···N1	0.88	2.23	2.626 (4)	107
O5—H5A···S1ⁱⁱ	0.84	2.82	3.106 (9)	102
C2—H2···O5ⁱⁱⁱ	0.95	2.65	3.335 (8)	129
N2—H2A···S1^iv	0.88	2.52	3.392 (4)	172
O4—H4···O4^v	0.84	2.16	2.988 (5)	169
C9—H9A···O3ⁱ	0.99	2.46	2.985 (5)	113

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

Experimental details

Crystal data
Chemical formula	C₁₀H₁₃N₃O₂S
M_r	239.29
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	91
a, b, c (Å)	10.6549 (12), 12.9020 (16), 8.6375 (11)
β (°)	107.910 (4)
V (Å³)	1129.9 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.28
Crystal size (mm)	0.44 × 0.11 × 0.09

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2006)
T_min, T_max	0.818, 0.975
No. of measured, independent and observed [I > 2σ(I)] reflections	12327, 1998, 1507
R_int	0.040
(sin θ/λ)_max (Å⁻¹)	0.596

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.059, 0.168, 1.05
No. of reflections	1998
No. of parameters	165
No. of restraints	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	1.41, −0.64

Computer programs: , APEX2 (Bruker 2006) and SAINT (Bruker 2006), SAINT (Bruker 2006), SHELXS97 (Sheldrick, 2008) and TITAN2000 (Hunter & Simpson, 1999), SHELXL97 (Sheldrick, 2008) and TITAN2000 (Hunter & Simpson, 1999), SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006), SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3B···N1	0.88	2.23	2.626 (4)	107
O5—H5A···S1ⁱ	0.84	2.82	3.106 (9)	102.3
C2—H2···O5ⁱⁱ	0.95	2.65	3.335 (8)	129.1
N2—H2A···S1ⁱⁱⁱ	0.88	2.52	3.392 (4)	172.0
O4—H4···O4^iv	0.84	2.16	2.988 (5)	168.8
C9—H9A···O3^v	0.99	2.46	2.985 (5)	112.6

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

Acknowledgements

We thank the Universiti Kebangsaan Malaysia and the Ministry of Higher Education, Malaysia, for supporting this research through grant UKM-ST-01-FRGS0022–2006. We also thank the University of Otago for purchase of the diffractometer.

References

Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335–338. Web of Science CrossRef CAS IUCr Journals Google Scholar
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