(Z)-2-(2-Hy­droxy-4-meth­oxy­benzyl­idene)-1-benzofuran-3(2H)-one

Satyanarayana Reddy, J.; Ravi Kumar, N.; Venkata Prasad, J.; Gopikrishna, G.; Anand Solomon, K.

doi:10.1107/S1600536811016217

organic compounds

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ISSN: 2056-9890

Volume 67| Part 6| June 2011| Page o1330

doi:10.1107/S1600536811016217

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(Z)-2-(2-Hydroxy-4-methoxybenzylidene)-1-benzofuran-3(2H)-one

J. Satyanarayana Reddy,^a N. Ravi Kumar,^a J. Venkata Prasad,^a G. Gopikrishna ^a and K. Anand Solomon ^a ^*

^aSankar Foundation Research Institute, Naiduthota, Vepagunta, Visakhapatnam, Andhra Pradesh 530 047, India
^*Correspondence e-mail: anand.dcb@gmail.com

(Received 16 April 2011; accepted 28 April 2011; online 7 May 2011)

In the title compound, C₁₆H₁₂O₄, the 1-benzofuranone unit is in a planar conformation [C—C—C—C = 179.69 (12)°]. The conformation around the C=C double bond [1.3370 (17) Å] is Z. In the crystal, the molecules are stabilized by O—H⋯O (running parallel to the bc plane) and C—H⋯O hydrogen bonds.

Related literature

For the synthesis and biological activity of substituted aurones, see: Varma & Varma (1992 ); Beney et al. (2001 ); Sim et al. (2008 ); Souard et al. (2010 ); Wang et al. (2007 ). For aurones as structural scaffolds in natural and synthetic compounds possessing diverse biological properties, see: Villemin et al. (1998 ). The title compound, which is an analogue of naturally occurring aurones, holds promise as an inhibitor against human melanocytes tyrosinase towards antihyperpigmentation, see: Okombi et al. (2006 ). For the assignment of conformations and the orientation of the substituents, see: Nardelli (1983 , 1995 ); Klyne & Prelog (1960 ).

Experimental

Crystal data

C₁₆H₁₂O₄
M_r = 268.26
Monoclinic, P 2₁ /n
a = 7.1083 (4) Å
b = 12.7072 (7) Å
c = 14.4024 (8) Å
β = 100.161 (2)°
V = 1280.52 (12) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 293 K
0.35 × 0.30 × 0.25 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2004 ) T_min = 0.906, T_max = 0.975
19357 measured reflections
4765 independent reflections
2533 reflections with I > 2σ(I)
R_int = 0.047

Refinement

R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.150
S = 1.02
4765 reflections
187 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.26 e Å⁻³
Δρ_min = −0.19 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3A⋯O2ⁱ	0.90 (2)	1.80 (2)	2.6952 (14)	170.0 (19)
C16—H16A⋯O3ⁱ	0.96	2.59	3.3328 (14)	135
Symmetry code: (i) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z-{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1993 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 (Farrugia, 1997 ) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811016217/ds2109sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811016217/ds2109Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811016217/ds2109Isup3.cml

checkCIF report

Comment top

Aurones are chalcone analogues containing fused benzofuranone ring system. They form essential structural scaffold in several natural and synthetic molecules possessing diverse biological properties (Villemin et al. 1998) Several functionalized aurones were reported to exhibit anti-malarial (Souard et al. 2010) and anti-histamine (Wang et al. 2007) properties. The title compound which is an analogue of naturally occurring aurones holds promise as inhibitors against human melanocytes tyrosinase towards antihyperpigmentation (Okombi et al. 2006).

Related literature top

For the synthesis and biological activity of substituted aurones, see: Varma et al. (1992); Beney et al. (2001); Sim et al. (2008); Souard et al. (2010); Wang et al. (2007). For aurones as structural scaffolds in natural and synthetic compounds possessing diverse biological properties, see: Villemin et al. (1998). The title compound, which is an analogue of naturally occurring aurones, holds promise as an inhibitor against human melanocytes tyrosinase towards antihyperpigmentation, see: Okombi et al. (2006). For the assignment of conformations and the orientation of the substituents, see: Nardelli (1983, 1995); Klyne & Prelog (1960).

Experimental top

3-coumaranone was allowed to react with 2-hydroxy-4-methoxybenzaldehyde (aldol condensation) in alcoholic solution in the presence of potassium hydroxide for 30 minutes to yield the title compound. The pure product was obtained by recrystalizing the crude product in ethanol solvent.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top

	Fig. 1. Reaction scheme.
	Fig. 2. ORTEP diagram of (Z)-2-(2-hydroxy-4-methoxybenzylidene)benzofuran-3(2H)-one. (Thermal ellipsoids are at 50% probability level).
	Fig. 3. Crystal packing diagram of the title compound. Symmetry codes -x + 1/2,y + 1/2,-z - 1/2

(Z)-2-(2-Hydroxy-4-methoxybenzylidene)-1-benzofuran-3(2H)-one top

Crystal data top

C₁₆H₁₂O₄	F(000) = 560
M_r = 268.26	D_x = 1.391 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 3249 reflections
a = 7.1083 (4) Å	θ = 2.9–25.3°
b = 12.7072 (7) Å	µ = 0.10 mm⁻¹
c = 14.4024 (8) Å	T = 293 K
β = 100.161 (2)°	Block, yellow
V = 1280.52 (12) Å³	0.35 × 0.30 × 0.25 mm
Z = 4

Data collection top

Bruker Kappa APEXII CCD diffractometer	4765 independent reflections
Radiation source: fine-focus sealed tube	2533 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.047
ω and ϕ scans	θ_max = 32.9°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −10→5
T_min = 0.906, T_max = 0.975	k = −17→19
19357 measured reflections	l = −21→21

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.052	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.150	w = 1/[σ²(F_o²) + (0.0683P)² + 0.0121P] where P = (F_o² + 2F_c²)/3
S = 1.02	(Δ/σ)_max = 0.001
4765 reflections	Δρ_max = 0.26 e Å⁻³
187 parameters	Δρ_min = −0.19 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0043 (16)

Crystal data top

C₁₆H₁₂O₄	V = 1280.52 (12) Å³
M_r = 268.26	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 7.1083 (4) Å	µ = 0.10 mm⁻¹
b = 12.7072 (7) Å	T = 293 K
c = 14.4024 (8) Å	0.35 × 0.30 × 0.25 mm
β = 100.161 (2)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	4765 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2004)	2533 reflections with I > 2σ(I)
T_min = 0.906, T_max = 0.975	R_int = 0.047
19357 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.052	0 restraints
wR(F²) = 0.150	H atoms treated by a mixture of independent and constrained refinement
S = 1.02	Δρ_max = 0.26 e Å⁻³
4765 reflections	Δρ_min = −0.19 e Å⁻³
187 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	0.33155 (18)	0.81587 (10)	0.10935 (9)	0.0378 (3)
C2	0.3577 (2)	0.79394 (12)	0.20448 (10)	0.0498 (4)
H2	0.3493	0.8460	0.2490	0.060*
C3	0.3967 (2)	0.69092 (12)	0.22996 (11)	0.0544 (4)
H3	0.4168	0.6732	0.2936	0.065*
C4	0.4072 (2)	0.61232 (12)	0.16407 (11)	0.0529 (4)
H4	0.4321	0.5433	0.1840	0.064*
C5	0.3811 (2)	0.63594 (11)	0.06989 (11)	0.0487 (4)
H5	0.3888	0.5838	0.0254	0.058*
C6	0.34267 (17)	0.73990 (10)	0.04224 (9)	0.0383 (3)
C7	0.31090 (19)	0.79320 (10)	−0.04815 (9)	0.0409 (3)
C8	0.27856 (18)	0.90379 (10)	−0.02558 (9)	0.0380 (3)
C9	0.24089 (17)	0.98235 (10)	−0.08784 (9)	0.0388 (3)
H9	0.2352	0.9621	−0.1503	0.047*
C10	0.20767 (16)	1.09256 (10)	−0.07510 (9)	0.0362 (3)
C11	0.2172 (2)	1.14095 (10)	0.01304 (10)	0.0440 (3)
H11	0.2418	1.0999	0.0673	0.053*
C12	0.1913 (2)	1.24709 (11)	0.02151 (10)	0.0492 (4)
H12	0.1987	1.2772	0.0809	0.059*
C13	0.15384 (19)	1.30956 (10)	−0.05866 (10)	0.0412 (3)
C14	0.14158 (17)	1.26536 (10)	−0.14673 (9)	0.0389 (3)
H14	0.1155	1.3072	−0.2004	0.047*
C15	0.16833 (18)	1.15787 (10)	−0.15485 (9)	0.0383 (3)
C16	0.0907 (2)	1.48154 (11)	−0.12239 (11)	0.0557 (4)
H16A	0.1933	1.4791	−0.1577	0.083*
H16B	0.0756	1.5523	−0.1015	0.083*
H16C	−0.0256	1.4589	−0.1617	0.083*
O1	0.29265 (13)	0.91457 (7)	0.07146 (6)	0.0425 (2)
O2	0.30983 (16)	0.75813 (8)	−0.12769 (7)	0.0611 (3)
O3	0.15733 (16)	1.11203 (8)	−0.24045 (7)	0.0558 (3)
O4	0.13342 (16)	1.41402 (8)	−0.04288 (7)	0.0556 (3)
H3A	0.153 (3)	1.1617 (15)	−0.2855 (16)	0.092 (7)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0425 (6)	0.0355 (7)	0.0351 (7)	−0.0041 (5)	0.0061 (5)	0.0037 (6)
C2	0.0625 (9)	0.0539 (9)	0.0334 (7)	−0.0009 (7)	0.0092 (6)	0.0034 (7)
C3	0.0590 (9)	0.0622 (10)	0.0417 (8)	0.0000 (7)	0.0081 (7)	0.0153 (8)
C4	0.0516 (8)	0.0457 (9)	0.0598 (10)	0.0006 (6)	0.0052 (7)	0.0184 (7)
C5	0.0538 (8)	0.0382 (8)	0.0518 (9)	0.0018 (6)	0.0032 (6)	0.0015 (7)
C6	0.0413 (6)	0.0349 (7)	0.0370 (7)	−0.0023 (5)	0.0021 (5)	0.0023 (5)
C7	0.0511 (7)	0.0367 (7)	0.0333 (7)	−0.0009 (6)	0.0029 (5)	−0.0028 (6)
C8	0.0476 (7)	0.0364 (7)	0.0299 (6)	−0.0026 (5)	0.0065 (5)	−0.0015 (5)
C9	0.0496 (7)	0.0357 (7)	0.0314 (6)	−0.0021 (5)	0.0079 (5)	−0.0001 (5)
C10	0.0419 (6)	0.0339 (7)	0.0339 (7)	−0.0024 (5)	0.0099 (5)	0.0007 (5)
C11	0.0608 (8)	0.0390 (7)	0.0347 (7)	0.0017 (6)	0.0154 (6)	0.0027 (6)
C12	0.0736 (9)	0.0420 (8)	0.0361 (8)	0.0030 (7)	0.0212 (7)	−0.0029 (6)
C13	0.0490 (7)	0.0324 (7)	0.0455 (8)	0.0011 (5)	0.0175 (6)	−0.0015 (6)
C14	0.0476 (7)	0.0336 (7)	0.0362 (7)	−0.0005 (5)	0.0096 (5)	0.0043 (5)
C15	0.0463 (7)	0.0354 (7)	0.0337 (7)	−0.0051 (5)	0.0086 (5)	−0.0018 (5)
C16	0.0749 (10)	0.0352 (8)	0.0597 (10)	0.0034 (7)	0.0194 (8)	0.0045 (7)
O1	0.0612 (6)	0.0353 (5)	0.0313 (5)	−0.0006 (4)	0.0092 (4)	0.0004 (4)
O2	0.1001 (9)	0.0452 (6)	0.0353 (6)	0.0094 (5)	0.0048 (5)	−0.0087 (5)
O3	0.1003 (8)	0.0346 (6)	0.0317 (5)	−0.0049 (5)	0.0092 (5)	−0.0017 (4)
O4	0.0859 (7)	0.0353 (6)	0.0495 (6)	0.0077 (5)	0.0222 (5)	−0.0011 (5)

Geometric parameters (Å, º) top

C1—O1	1.3764 (15)	C9—H9	0.9300
C1—C6	1.3781 (19)	C10—C11	1.4014 (18)
C1—C2	1.3782 (19)	C10—C15	1.4046 (18)
C2—C3	1.374 (2)	C11—C12	1.3696 (18)
C2—H2	0.9300	C11—H11	0.9300
C3—C4	1.389 (2)	C12—C13	1.3876 (19)
C3—H3	0.9300	C12—H12	0.9300
C4—C5	1.370 (2)	C13—O4	1.3588 (16)
C4—H4	0.9300	C13—C14	1.3758 (18)
C5—C6	1.3927 (18)	C14—C15	1.3868 (18)
C5—H5	0.9300	C14—H14	0.9300
C6—C7	1.4495 (18)	C15—O3	1.3533 (16)
C7—O2	1.2280 (16)	C16—O4	1.4203 (17)
C7—C8	1.4697 (18)	C16—H16A	0.9600
C8—C9	1.3370 (17)	C16—H16B	0.9600
C8—O1	1.3902 (15)	C16—H16C	0.9600
C9—C10	1.4373 (17)	O3—H3A	0.90 (2)

O1—C1—C6	113.12 (11)	C11—C10—C15	116.89 (12)
O1—C1—C2	124.11 (12)	C11—C10—C9	124.08 (12)
C6—C1—C2	122.77 (12)	C15—C10—C9	119.01 (11)
C3—C2—C1	116.33 (14)	C12—C11—C10	121.80 (13)
C3—C2—H2	121.8	C12—C11—H11	119.1
C1—C2—H2	121.8	C10—C11—H11	119.1
C2—C3—C4	122.35 (14)	C11—C12—C13	119.89 (13)
C2—C3—H3	118.8	C11—C12—H12	120.1
C4—C3—H3	118.8	C13—C12—H12	120.1
C5—C4—C3	120.32 (14)	O4—C13—C14	124.18 (12)
C5—C4—H4	119.8	O4—C13—C12	115.47 (12)
C3—C4—H4	119.8	C14—C13—C12	120.34 (12)
C4—C5—C6	118.46 (14)	C13—C14—C15	119.51 (12)
C4—C5—H5	120.8	C13—C14—H14	120.2
C6—C5—H5	120.8	C15—C14—H14	120.2
C1—C6—C5	119.77 (13)	O3—C15—C14	120.93 (12)
C1—C6—C7	106.47 (11)	O3—C15—C10	117.50 (12)
C5—C6—C7	133.75 (13)	C14—C15—C10	121.57 (12)
O2—C7—C6	130.00 (13)	O4—C16—H16A	109.5
O2—C7—C8	125.30 (13)	O4—C16—H16B	109.5
C6—C7—C8	104.70 (11)	H16A—C16—H16B	109.5
C9—C8—O1	124.83 (12)	O4—C16—H16C	109.5
C9—C8—C7	125.89 (12)	H16A—C16—H16C	109.5
O1—C8—C7	109.29 (10)	H16B—C16—H16C	109.5
C8—C9—C10	131.29 (12)	C1—O1—C8	106.42 (10)
C8—C9—H9	114.4	C15—O3—H3A	110.1 (13)
C10—C9—H9	114.4	C13—O4—C16	117.98 (11)

O1—C1—C2—C3	−179.59 (12)	C8—C9—C10—C11	2.7 (2)
C6—C1—C2—C3	0.2 (2)	C8—C9—C10—C15	−179.18 (13)
C1—C2—C3—C4	−0.8 (2)	C15—C10—C11—C12	−0.59 (19)
C2—C3—C4—C5	0.9 (2)	C9—C10—C11—C12	177.54 (13)
C3—C4—C5—C6	−0.4 (2)	C10—C11—C12—C13	0.2 (2)
O1—C1—C6—C5	−179.94 (11)	C11—C12—C13—O4	−178.96 (13)
C2—C1—C6—C5	0.23 (19)	C11—C12—C13—C14	0.4 (2)
O1—C1—C6—C7	0.83 (14)	O4—C13—C14—C15	178.78 (12)
C2—C1—C6—C7	−178.99 (12)	C12—C13—C14—C15	−0.47 (19)
C4—C5—C6—C1	−0.12 (19)	C13—C14—C15—O3	−179.95 (11)
C4—C5—C6—C7	178.85 (14)	C13—C14—C15—C10	0.05 (18)
C1—C6—C7—O2	179.03 (14)	C11—C10—C15—O3	−179.53 (11)
C5—C6—C7—O2	0.0 (3)	C9—C10—C15—O3	2.24 (17)
C1—C6—C7—C8	−0.86 (14)	C11—C10—C15—C14	0.47 (18)
C5—C6—C7—C8	−179.93 (14)	C9—C10—C15—C14	−177.76 (11)
O2—C7—C8—C9	0.9 (2)	C6—C1—O1—C8	−0.43 (14)
C6—C7—C8—C9	−179.20 (12)	C2—C1—O1—C8	179.39 (12)
O2—C7—C8—O1	−179.27 (13)	C9—C8—O1—C1	179.68 (12)
C6—C7—C8—O1	0.63 (14)	C7—C8—O1—C1	−0.15 (13)
O1—C8—C9—C10	0.5 (2)	C14—C13—O4—C16	2.1 (2)
C7—C8—C9—C10	−179.69 (12)	C12—C13—O4—C16	−178.64 (13)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O2ⁱ	0.90 (2)	1.80 (2)	2.6952 (14)	170.0 (19)
C16—H16A···O3ⁱ	0.96	2.59	3.3328 (14)	135

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

Experimental details

Crystal data
Chemical formula	C₁₆H₁₂O₄
M_r	268.26
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	293
a, b, c (Å)	7.1083 (4), 12.7072 (7), 14.4024 (8)
β (°)	100.161 (2)
V (Å³)	1280.52 (12)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.35 × 0.30 × 0.25

Data collection
Diffractometer	Bruker Kappa APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2004)
T_min, T_max	0.906, 0.975
No. of measured, independent and observed [I > 2σ(I)] reflections	19357, 4765, 2533
R_int	0.047
(sin θ/λ)_max (Å⁻¹)	0.764

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.150, 1.02
No. of reflections	4765
No. of parameters	187
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.26, −0.19

Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT (Bruker, 2004), SAINT and XPREP (Bruker, 2004), SIR92 (Altomare et al., 1993), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O2ⁱ	0.90 (2)	1.80 (2)	2.6952 (14)	170.0 (19)
C16—H16A···O3ⁱ	0.96	2.59	3.3328 (14)	135

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

Acknowledgements

The authors thank the Managing Trustee and the Founder Trustee of the Sankar Foundation for their financial support and encouragement. We also acknowledge the Head of the SAIF, IIT-Chennai, for the data collection.

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