3,4,5-Trihydr­oxy-N′-[(1-methyl-1H-indol-2-yl)methyl­idene]benzohydrazide

Khaledi, H.; Saharin, S.M.; Mohd Ali, H.; Robinson, W.T.; Abdulla, M.A.

doi:10.1107/S1600536809027032

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 65| Part 8| August 2009| Page o1920

doi:10.1107/S1600536809027032

Open

access

3,4,5-Trihydroxy-N′-[(1-methyl-1H-indol-2-yl)methylidene]benzohydrazide

Hamid Khaledi,^a Siti Munirah Saharin,^a Hapipah Mohd Ali,^a ^* Ward T. Robinson ^a and Mahmood A. Abdulla ^b

^aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, and ^bDepartment of Molecular Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: hapipah@um.edu.my

(Received 30 June 2009; accepted 10 July 2009; online 18 July 2009)

The structure of the title compound, C₁₇H₁₅N₃O₄, displays intermolecular O—H⋯N and O—H⋯O hydrogen bonding between adjacent molecules. Intramolecular O—H⋯O hydrogen bonds also occur. The molecule is essentially planar with a deviation of 0.090 (1) Å from the best plane running through the connected ring systems.

Related literature

For related compounds see: Khaledi et al. (2008a ,b , 2009 ).

Experimental

Crystal data

C₁₇H₁₅N₃O₄
M_r = 325.32
Monoclinic, P 2₁ /n
a = 9.0839 (2) Å
b = 13.1684 (3) Å
c = 12.4414 (3) Å
β = 104.2740 (10)°
V = 1442.30 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 100 K
0.49 × 0.16 × 0.09 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.948, T_max = 0.991
10177 measured reflections
4070 independent reflections
3153 reflections with I > 2σ(I)
R_int = 0.019

Refinement

R[F² > 2σ(F²)] = 0.044
wR(F²) = 0.127
S = 0.99
4070 reflections
221 parameters
H-atom parameters constrained
Δρ_max = 0.63 e Å⁻³
Δρ_min = −0.26 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2O⋯O4ⁱ	0.84	1.80	2.6119 (14)	164
O1—H1O⋯N2ⁱ	0.84	2.06	2.7759 (15)	142
O3—H3O⋯O2ⁱⁱ	0.84	2.12	2.8469 (14)	144
O1—H1O⋯O2	0.84	2.51	2.8570 (14)	106
O3—H3O⋯O2	0.84	2.31	2.7560 (14)	113
Symmetry codes: (i) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) -x+2, -y, -z.

Data collection: APEX2 (Bruker, 2007 ); cell refinement: APEX2; 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: X-SEED (Barbour, 2001 ); software used to prepare material for publication: publCIF (Westrip, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809027032/hg2532sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809027032/hg2532Isup2.hkl

checkCIF report

Related literature top

For related compounds see: Khaledi et al. (2008a,b) and Khaledi et al. (2009)

Experimental top

A mixture of 1-Methylindole-2-carboxaldehyde (0.80 g, 5 mmol) and 3,4,5-trihydroxybenzoylhydrazine(0.92 g, 5 mmol) in the presence of acetic acid (1 ml) was heated in ethanol (70 ml) for 6 h. The solution was then cooled and filtered to remove the unreacted hydrazine. The filtrate was poured to water (400 ml), the solid product formed were filtered off, washed with diethyl ether,and dried in an oven. Suitable crystals for X-ray analysis were obtained by slow evaporation of an ethanol solution at room temperature.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: APEX2 (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: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2009).

Figures top

Fig. 1. Thermal ellipsoid plot (Barbour, 2001) of the title compound at 70% probability level. Hydrogen atoms are drawn as spheres of arbitrary radius.

3,4,5-Trihydroxy-N'-[(1-methyl-1H-indol-2- yl)methylidene]benzohydrazide top

Crystal data top

C₁₇H₁₅N₃O₄	F(000) = 680
M_r = 325.32	D_x = 1.498 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 3739 reflections
a = 9.0839 (2) Å	θ = 2.3–30.4°
b = 13.1684 (3) Å	µ = 0.11 mm⁻¹
c = 12.4414 (3) Å	T = 100 K
β = 104.274 (1)°	Block, green
V = 1442.30 (6) Å³	0.49 × 0.16 × 0.09 mm
Z = 4

Data collection top

Bruker APEXII CCD area-detector diffractometer	4070 independent reflections
Radiation source: fine-focus sealed tube	3153 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.019
ω scans	θ_max = 30.5°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −9→12
T_min = 0.948, T_max = 0.991	k = −18→18
10177 measured reflections	l = −17→14

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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.127	H-atom parameters constrained
S = 0.99	w = 1/[σ²(F_o²) + (0.0672P)² + 0.9156P] where P = (F_o² + 2F_c²)/3
4070 reflections	(Δ/σ)_max < 0.001
221 parameters	Δρ_max = 0.63 e Å⁻³
0 restraints	Δρ_min = −0.26 e Å⁻³

Crystal data top

C₁₇H₁₅N₃O₄	V = 1442.30 (6) Å³
M_r = 325.32	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 9.0839 (2) Å	µ = 0.11 mm⁻¹
b = 13.1684 (3) Å	T = 100 K
c = 12.4414 (3) Å	0.49 × 0.16 × 0.09 mm
β = 104.274 (1)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	4070 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3153 reflections with I > 2σ(I)
T_min = 0.948, T_max = 0.991	R_int = 0.019
10177 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.044	0 restraints
wR(F²) = 0.127	H-atom parameters constrained
S = 0.99	Δρ_max = 0.63 e Å⁻³
4070 reflections	Δρ_min = −0.26 e Å⁻³
221 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
N1	0.47487 (13)	0.36671 (9)	0.05923 (10)	0.0132 (2)
H1N	0.4655	0.3333	−0.0034	0.016*
N2	0.38051 (13)	0.44784 (9)	0.06479 (10)	0.0134 (2)
N3	0.06173 (13)	0.56577 (9)	−0.13005 (10)	0.0151 (2)
O1	0.99391 (12)	0.12533 (8)	0.33141 (8)	0.0165 (2)
H1O	1.0219	0.0645	0.3313	0.025*
O2	0.98618 (11)	0.01716 (7)	0.13104 (8)	0.0149 (2)
H2O	0.9766	−0.0305	0.1737	0.022*
O3	0.77044 (12)	0.07206 (8)	−0.05744 (8)	0.0189 (2)
H3O	0.8473	0.0349	−0.0506	0.028*
O4	0.59664 (13)	0.38379 (8)	0.23996 (8)	0.0199 (2)
C1	0.04811 (18)	0.51469 (13)	−0.23489 (13)	0.0226 (3)
H1A	−0.0426	0.5393	−0.2887	0.034*
H1B	0.0393	0.4413	−0.2247	0.034*
H1C	0.1383	0.5288	−0.2623	0.034*
C2	−0.02892 (15)	0.64421 (11)	−0.11137 (12)	0.0155 (3)
C3	−0.15129 (16)	0.69271 (11)	−0.18421 (13)	0.0192 (3)
H3	−0.1834	0.6736	−0.2600	0.023*
C4	−0.22304 (17)	0.76936 (12)	−0.14091 (14)	0.0213 (3)
H4	−0.3059	0.8039	−0.1883	0.026*
C5	−0.17667 (17)	0.79760 (11)	−0.02853 (14)	0.0219 (3)
H5	−0.2291	0.8505	−0.0016	0.026*
C6	−0.05636 (17)	0.74988 (11)	0.04323 (13)	0.0195 (3)
H6	−0.0259	0.7692	0.1191	0.023*
C7	0.02010 (16)	0.67213 (11)	0.00177 (12)	0.0163 (3)
C8	0.14341 (16)	0.60759 (11)	0.05098 (12)	0.0162 (3)
H8	0.1997	0.6085	0.1263	0.019*
C9	0.16628 (15)	0.54349 (10)	−0.03077 (11)	0.0137 (3)
C10	0.27384 (15)	0.46201 (10)	−0.02389 (11)	0.0134 (3)
H10	0.2662	0.4180	−0.0856	0.016*
C11	0.58127 (15)	0.33924 (10)	0.15038 (11)	0.0129 (3)
C12	0.68091 (14)	0.25165 (10)	0.13972 (11)	0.0123 (3)
C13	0.78798 (15)	0.22437 (10)	0.23633 (11)	0.0132 (3)
H13	0.7917	0.2597	0.3035	0.016*
C14	0.88907 (15)	0.14590 (10)	0.23472 (11)	0.0128 (3)
C15	0.88441 (15)	0.09305 (10)	0.13689 (11)	0.0122 (2)
C16	0.77684 (15)	0.12083 (10)	0.04008 (11)	0.0135 (3)
C17	0.67475 (15)	0.19925 (10)	0.04105 (11)	0.0143 (3)
H17	0.6014	0.2171	−0.0249	0.017*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0140 (5)	0.0112 (5)	0.0140 (5)	0.0024 (4)	0.0029 (4)	−0.0013 (4)
N2	0.0120 (5)	0.0110 (5)	0.0173 (5)	0.0015 (4)	0.0040 (4)	0.0006 (4)
N3	0.0132 (5)	0.0141 (5)	0.0174 (6)	0.0019 (4)	0.0028 (4)	0.0011 (4)
O1	0.0180 (5)	0.0172 (5)	0.0121 (4)	0.0047 (4)	−0.0006 (4)	0.0011 (4)
O2	0.0183 (5)	0.0122 (5)	0.0157 (5)	0.0049 (4)	0.0069 (4)	0.0039 (4)
O3	0.0196 (5)	0.0214 (5)	0.0139 (5)	0.0075 (4)	0.0010 (4)	−0.0046 (4)
O4	0.0232 (5)	0.0203 (5)	0.0151 (5)	0.0068 (4)	0.0027 (4)	−0.0035 (4)
C1	0.0219 (7)	0.0248 (8)	0.0192 (7)	0.0035 (6)	0.0014 (6)	−0.0027 (6)
C2	0.0135 (6)	0.0124 (6)	0.0219 (7)	0.0001 (5)	0.0066 (5)	0.0025 (5)
C3	0.0148 (6)	0.0182 (7)	0.0247 (7)	0.0009 (5)	0.0050 (5)	0.0049 (6)
C4	0.0151 (6)	0.0168 (7)	0.0325 (8)	0.0031 (5)	0.0070 (6)	0.0071 (6)
C5	0.0185 (7)	0.0134 (6)	0.0370 (9)	0.0020 (5)	0.0128 (6)	0.0013 (6)
C6	0.0193 (7)	0.0154 (7)	0.0263 (8)	−0.0008 (5)	0.0101 (6)	−0.0018 (5)
C7	0.0149 (6)	0.0129 (6)	0.0220 (7)	−0.0004 (5)	0.0068 (5)	0.0009 (5)
C8	0.0155 (6)	0.0142 (6)	0.0197 (7)	0.0003 (5)	0.0061 (5)	0.0004 (5)
C9	0.0122 (6)	0.0123 (6)	0.0165 (6)	−0.0002 (5)	0.0034 (5)	0.0022 (5)
C10	0.0125 (6)	0.0126 (6)	0.0155 (6)	−0.0008 (5)	0.0042 (5)	−0.0007 (5)
C11	0.0134 (6)	0.0121 (6)	0.0135 (6)	0.0001 (5)	0.0042 (5)	0.0011 (5)
C12	0.0122 (6)	0.0116 (6)	0.0131 (6)	0.0007 (4)	0.0031 (5)	0.0013 (5)
C13	0.0148 (6)	0.0131 (6)	0.0120 (6)	0.0008 (5)	0.0034 (5)	−0.0004 (5)
C14	0.0131 (6)	0.0132 (6)	0.0117 (6)	0.0001 (5)	0.0022 (4)	0.0029 (5)
C15	0.0120 (6)	0.0111 (6)	0.0142 (6)	0.0012 (4)	0.0042 (5)	0.0020 (5)
C16	0.0147 (6)	0.0142 (6)	0.0120 (6)	0.0006 (5)	0.0038 (5)	−0.0016 (5)
C17	0.0142 (6)	0.0147 (6)	0.0129 (6)	0.0025 (5)	0.0013 (5)	0.0007 (5)

Geometric parameters (Å, º) top

N1—C11	1.3455 (17)	C4—C5	1.407 (2)
N1—N2	1.3821 (15)	C4—H4	0.9500
N1—H1N	0.8800	C5—C6	1.380 (2)
N2—C10	1.2900 (17)	C5—H5	0.9500
N3—C2	1.3760 (18)	C6—C7	1.405 (2)
N3—C9	1.3912 (17)	C6—H6	0.9500
N3—C1	1.4455 (19)	C7—C8	1.419 (2)
O1—C14	1.3647 (16)	C8—C9	1.376 (2)
O1—H1O	0.8400	C8—H8	0.9500
O2—C15	1.3755 (16)	C9—C10	1.4394 (19)
O2—H2O	0.8400	C10—H10	0.9500
O3—C16	1.3613 (16)	C11—C12	1.4921 (18)
O3—H3O	0.8400	C12—C13	1.3941 (18)
O4—C11	1.2365 (17)	C12—C17	1.3972 (18)
C1—H1A	0.9800	C13—C14	1.3859 (18)
C1—H1B	0.9800	C13—H13	0.9500
C1—H1C	0.9800	C14—C15	1.3936 (18)
C2—C3	1.403 (2)	C15—C16	1.3995 (18)
C2—C7	1.416 (2)	C16—C17	1.3900 (19)
C3—C4	1.381 (2)	C17—H17	0.9500
C3—H3	0.9500

C11—N1—N2	119.41 (11)	C6—C7—C8	133.41 (14)
C11—N1—H1N	120.3	C2—C7—C8	107.14 (12)
N2—N1—H1N	120.3	C9—C8—C7	107.18 (13)
C10—N2—N1	114.41 (11)	C9—C8—H8	126.4
C2—N3—C9	108.32 (12)	C7—C8—H8	126.4
C2—N3—C1	125.46 (12)	C8—C9—N3	109.41 (12)
C9—N3—C1	126.22 (12)	C8—C9—C10	129.58 (13)
C14—O1—H1O	109.5	N3—C9—C10	120.98 (12)
C15—O2—H2O	109.5	N2—C10—C9	120.95 (13)
C16—O3—H3O	109.5	N2—C10—H10	119.5
N3—C1—H1A	109.5	C9—C10—H10	119.5
N3—C1—H1B	109.5	O4—C11—N1	122.01 (12)
H1A—C1—H1B	109.5	O4—C11—C12	120.71 (12)
N3—C1—H1C	109.5	N1—C11—C12	117.28 (12)
H1A—C1—H1C	109.5	C13—C12—C17	119.91 (12)
H1B—C1—H1C	109.5	C13—C12—C11	115.60 (12)
N3—C2—C3	130.13 (14)	C17—C12—C11	124.48 (12)
N3—C2—C7	107.95 (12)	C14—C13—C12	120.23 (12)
C3—C2—C7	121.92 (13)	C14—C13—H13	119.9
C4—C3—C2	117.12 (14)	C12—C13—H13	119.9
C4—C3—H3	121.4	O1—C14—C13	117.13 (12)
C2—C3—H3	121.4	O1—C14—C15	122.35 (12)
C3—C4—C5	121.76 (14)	C13—C14—C15	120.49 (12)
C3—C4—H4	119.1	O2—C15—C14	122.20 (12)
C5—C4—H4	119.1	O2—C15—C16	118.70 (12)
C6—C5—C4	121.17 (14)	C14—C15—C16	119.04 (12)
C6—C5—H5	119.4	O3—C16—C17	118.44 (12)
C4—C5—H5	119.4	O3—C16—C15	120.73 (12)
C5—C6—C7	118.60 (15)	C17—C16—C15	120.83 (12)
C5—C6—H6	120.7	C16—C17—C12	119.49 (12)
C7—C6—H6	120.7	C16—C17—H17	120.3
C6—C7—C2	119.43 (13)	C12—C17—H17	120.3

C11—N1—N2—C10	−173.94 (12)	C8—C9—C10—N2	−9.1 (2)
C9—N3—C2—C3	−179.04 (14)	N3—C9—C10—N2	172.91 (13)
C1—N3—C2—C3	0.1 (2)	N2—N1—C11—O4	0.8 (2)
C9—N3—C2—C7	0.29 (15)	N2—N1—C11—C12	−179.57 (11)
C1—N3—C2—C7	179.39 (13)	O4—C11—C12—C13	0.73 (19)
N3—C2—C3—C4	179.14 (14)	N1—C11—C12—C13	−178.95 (12)
C7—C2—C3—C4	−0.1 (2)	O4—C11—C12—C17	−177.78 (13)
C2—C3—C4—C5	−0.4 (2)	N1—C11—C12—C17	2.5 (2)
C3—C4—C5—C6	0.3 (2)	C17—C12—C13—C14	0.5 (2)
C4—C5—C6—C7	0.2 (2)	C11—C12—C13—C14	−178.13 (12)
C5—C6—C7—C2	−0.7 (2)	C12—C13—C14—O1	177.99 (12)
C5—C6—C7—C8	−178.83 (15)	C12—C13—C14—C15	−0.4 (2)
N3—C2—C7—C6	−178.74 (13)	O1—C14—C15—O2	−0.6 (2)
C3—C2—C7—C6	0.7 (2)	C13—C14—C15—O2	177.66 (12)
N3—C2—C7—C8	−0.15 (16)	O1—C14—C15—C16	−177.82 (12)
C3—C2—C7—C8	179.24 (13)	C13—C14—C15—C16	0.4 (2)
C6—C7—C8—C9	178.27 (16)	O2—C15—C16—O3	1.6 (2)
C2—C7—C8—C9	−0.04 (16)	C14—C15—C16—O3	178.93 (12)
C7—C8—C9—N3	0.22 (16)	O2—C15—C16—C17	−177.94 (12)
C7—C8—C9—C10	−177.98 (14)	C14—C15—C16—C17	−0.6 (2)
C2—N3—C9—C8	−0.32 (16)	O3—C16—C17—C12	−178.85 (12)
C1—N3—C9—C8	−179.42 (13)	C15—C16—C17—C12	0.7 (2)
C2—N3—C9—C10	178.06 (12)	C13—C12—C17—C16	−0.6 (2)
C1—N3—C9—C10	−1.0 (2)	C11—C12—C17—C16	177.82 (13)
N1—N2—C10—C9	179.93 (12)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2O···O4ⁱ	0.84	1.80	2.6119 (14)	164
O1—H1O···N2ⁱ	0.84	2.06	2.7759 (15)	142
O3—H3O···O2ⁱⁱ	0.84	2.12	2.8469 (14)	144
O1—H1O···O2	0.84	2.51	2.8570 (14)	106
O3—H3O···O2	0.84	2.31	2.7560 (14)	113

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

Experimental details

Crystal data
Chemical formula	C₁₇H₁₅N₃O₄
M_r	325.32
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	100
a, b, c (Å)	9.0839 (2), 13.1684 (3), 12.4414 (3)
β (°)	104.274 (1)
V (Å³)	1442.30 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.49 × 0.16 × 0.09

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.948, 0.991
No. of measured, independent and observed [I > 2σ(I)] reflections	10177, 4070, 3153
R_int	0.019
(sin θ/λ)_max (Å⁻¹)	0.715

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.044, 0.127, 0.99
No. of reflections	4070
No. of parameters	221
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.63, −0.26

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2O···O4ⁱ	0.84	1.80	2.6119 (14)	163.5
O1—H1O···N2ⁱ	0.84	2.06	2.7759 (15)	142.4
O3—H3O···O2ⁱⁱ	0.84	2.12	2.8469 (14)	144.3
O1—H1O···O2	0.84	2.51	2.8570 (14)	105.9
O3—H3O···O2	0.84	2.31	2.7560 (14)	113.4

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

Acknowledgements

The authors thank the University of Malaya for funding this study (FRGS grant No. FP009/2008 C).

References

Barbour, L. J. (2001). J. Supramol. Chem. 1, 189–191. CrossRef CAS Google Scholar
Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.. Google Scholar
Khaledi, H., Mohd Ali, H. & Ng, S. W. (2008a). Acta Cryst. E64, o2108. Web of Science CSD CrossRef IUCr Journals Google Scholar
Khaledi, H., Mohd Ali, H. & Ng, S. W. (2008b). Acta Cryst. E64, o2481. Web of Science CSD CrossRef IUCr Journals Google Scholar
Khaledi, H., Mohd Ali, H. & Ng, S. W. (2009). Acta Cryst. E65, o169. Web of Science CSD CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Westrip, S. P. (2009). publCIF. In preparation. Google Scholar