organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 71| Part 2| February 2015| Pages o70-o71

Crystal structure of ethyl 2-(2-{(1E)-[(E)-2-(2-hy­dr­oxy­benzyl­­idene)hydrazin-1-yl­­idene]meth­yl}phen­­oxy)acetate

aDepartment of Physics, Faculty of Sciences, Erciyes University, 38039 Kayseri, Turkey, bDepartment of Chemistry, Tulane University, New Orleans, LA 70118, USA, cChemistry and Environmental Division, Manchester Metropolitan University, Manchester M1 5GD, England, dChemistry Department, Faculty of Science, Minia University, 61519 El-Minia, Egypt, eChemistry Department, Faculty of Science, Sohag University, 82524 Sohag, Egypt, and fKirkuk University, College of Science, Department of Chemistry, Kirkuk, Iraq
*Correspondence e-mail: shaabankamel@yahoo.com

Edited by D.-J. Xu, Zhejiang University (Yuquan Campus), China (Received 11 December 2014; accepted 13 December 2014; online 3 January 2015)

In the title compound, C18H18N2O4, the planes of the benzene rings are twisted with respect to each other at 27.25 (7)°. The mol­ecule displays an extended conformation with an intra­molecular O—H⋯N hydrogen bond. In the crystal, weak C—H⋯O inter­actions link the mol­ecules, forming supra­molecular chains running along the b-axis direction.

1. Related literature

For a similar structure, see: Mague et al. (2015[Mague, J. T., Mohamed, S. K., Akkurt, M., Ahmed, E. A. & Omran, O. A. (2015). Acta Cryst. E71, o16.]). For background to related Schiff base ligands and their biological activity, see: Adsule et al. (2006[Adsule, S., Barve, V., Chen, D., Ahmed, F., Dou, Q. P., Padhye, S. & Sarkar, F. H. (2006). J. Med. Chem. 49, 7242-7246.]); Karthikeyan et al. (2006[Karthikeyan, M. S., Prasad, D. J., Poojary, B., Bhat, K. S., Holla, B. S. & Kumari, N. S. (2006). Bioorg. Med. Chem. 14, 7482-7489.]); Amimoto & Kawato (2005[Amimoto, K. & Kawato, T. (2005). J. Photochem. Photobiol. Photochem. Rev. 6, 207-226.]); Cohen & Schmidt (1964[Cohen, M. D. & Schmidt, G. M. J. (1964). J. Chem. Soc. pp. 1996-2000.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C18H18N2O4

  • Mr = 326.34

  • Monoclinic, P 21 /n

  • a = 17.6846 (4) Å

  • b = 4.8645 (1) Å

  • c = 19.2235 (4) Å

  • β = 107.357 (1)°

  • V = 1578.43 (6) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 0.81 mm−1

  • T = 150 K

  • 0.20 × 0.09 × 0.06 mm

2.2. Data collection

  • Bruker D8 VENTURE PHOTON 100 CMOS diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.90, Tmax = 0.95

  • 11331 measured reflections

  • 3063 independent reflections

  • 2538 reflections with I > 2σ(I)

  • Rint = 0.031

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.038

  • wR(F2) = 0.109

  • S = 1.06

  • 3063 reflections

  • 218 parameters

  • H-atom parameters constrained

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1A⋯N1 0.84 1.85 2.6441 (17) 158
C15—H15A⋯O4i 0.99 2.58 3.3568 (19) 136
C15—H15B⋯O3ii 0.99 2.57 3.440 (2) 147
Symmetry codes: (i) -x+1, -y+3, -z+1; (ii) x, y+1, z.

Data collection: APEX2 (Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXT (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: DIAMOND (Brandenburg & Putz, 2012[Brandenburg, K. & Putz, H. (2012). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

Schiff bases of salicylaldehyde have gained importance from physiological and pharmacological activities point of view (Adsule et al., 2006; Karthikeyan et al., 2006). They also may exhibit thermochromism or photochromism depending on the planarity or nonplanarity, respectively, of the molecule (Amimoto & Kawato, 2005; Cohen & Schmidt, 1964). As part of our research efforts in the area of schiff base ligands we report in this study the synthesis and crystal structure determination of the title compound.

The title molecule is in an extended conformation with the phenyl rings C1–C6 and C9–C14, respectively, making dihedral angles of 7.4 (1)° and 19.8 (1)° with the mean plane of the central C7, N1, N2, C8 unit. The bond lengths and bond angles of the title molecule are normal and are comparable to those reported for a similar structure (Mague et al., 2015).

The former angle is smaller as a result of the intramolecular O1—H1a···N1 hydrogen bond (Table 1). The packing consists of chains of molecules formed by weak C15—H15B···O3 interactions running parallel to the b axis with adjacent pairs of chains associated via C15—H15a···O4 interactions across centers of symmetry (Fig. 2 and Table 1).

Related literature top

For a similar structure, see: Mague et al. (2015). For background to related Schiff base ligands and their biological activity, see: Adsule et al. (2006); Karthikeyan et al. (2006); Amimoto & Kawato (2005); Cohen & Schmidt (1964).

Experimental top

A mixture of 0.01 mol of 2-hydroxybenzohydrazide and 0.01 mol of ethyl 2-(2-formylphenoxy)acetate in 20 ml of ethanol was heated under reflux for 2 h. The solid product which precipitated from the hot solution was collected by filtration and dried under vacuum. Colourless crystals sufficient for X-ray diffraction were obtained by recrystallization from an ethanol solution. m.p. 428 K, yield 92%.

Refinement top

H-atoms attached to carbon were placed in calculated positions (C—H = 0.95 - 0.99 Å) and refined in riding mode while hydroxyl-O atom was located in a difference Fourier map and refined by riding in its as-found relative position to oxygen atom. Uiso(H) = 1.5Ueq(C) for methyl H toms and 1.2Ueq(C,O) for the others.

Computing details top

Data collection: APEX2 (Bruker, 2014); cell refinement: SAINT (Bruker, 2014); data reduction: SAINT (Bruker, 2014); program(s) used to solve structure: SHELXT (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2012); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Perspective view of the title molecule with 50% probability ellipsoids and showing the atom labeling scheme and the intramolecular O—H···N hydrogen bond.
[Figure 2] Fig. 2. Packing viewed down the b axis showing C—H···O interactions as black dotted lines.
Ethyl 2-(2-{(1E)-[(E)-2-(2-hydroxybenzylidene)hydrazin-1-ylidene]methyl}phenoxy)acetate top
Crystal data top
C18H18N2O4F(000) = 688
Mr = 326.34Dx = 1.373 Mg m3
Monoclinic, P21/nCu Kα radiation, λ = 1.54178 Å
a = 17.6846 (4) ÅCell parameters from 6837 reflections
b = 4.8645 (1) Åθ = 4.1–72.5°
c = 19.2235 (4) ŵ = 0.81 mm1
β = 107.357 (1)°T = 150 K
V = 1578.43 (6) Å3Column, colourless
Z = 40.20 × 0.09 × 0.06 mm
Data collection top
Bruker D8 VENTURE PHOTON 100 CMOS
diffractometer
3063 independent reflections
Radiation source: INCOATEC IµS micro–focus source2538 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.031
Detector resolution: 10.4167 pixels mm-1θmax = 72.5°, θmin = 3.0°
ω scansh = 1821
Absorption correction: multi-scan
(SADABS; Bruker, 2014)
k = 56
Tmin = 0.90, Tmax = 0.95l = 2323
11331 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.109H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.0535P)2 + 0.5415P]
where P = (Fo2 + 2Fc2)/3
3063 reflections(Δ/σ)max < 0.001
218 parametersΔρmax = 0.24 e Å3
0 restraintsΔρmin = 0.21 e Å3
Crystal data top
C18H18N2O4V = 1578.43 (6) Å3
Mr = 326.34Z = 4
Monoclinic, P21/nCu Kα radiation
a = 17.6846 (4) ŵ = 0.81 mm1
b = 4.8645 (1) ÅT = 150 K
c = 19.2235 (4) Å0.20 × 0.09 × 0.06 mm
β = 107.357 (1)°
Data collection top
Bruker D8 VENTURE PHOTON 100 CMOS
diffractometer
3063 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2014)
2538 reflections with I > 2σ(I)
Tmin = 0.90, Tmax = 0.95Rint = 0.031
11331 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0380 restraints
wR(F2) = 0.109H-atom parameters constrained
S = 1.06Δρmax = 0.24 e Å3
3063 reflectionsΔρmin = 0.21 e Å3
218 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. H-atoms attached to carbon were placed in calculated positions (C—H = 0.95 - 0.99 Å) while that attached to oxygen was placed in a location derived from a difference map and its parameters adjusted to give O—H = 0.84 Å. All were included as riding contributions with isotropic displacement parameters 1.2 - 1.5 times those of the attached atoms.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.26107 (6)0.1064 (3)0.62511 (6)0.0392 (3)
H1A0.24500.22560.59240.047*
O20.33072 (6)1.1408 (2)0.46429 (6)0.0318 (3)
O30.42576 (7)0.9110 (2)0.38921 (7)0.0394 (3)
O40.49863 (7)1.2963 (2)0.40435 (6)0.0365 (3)
N10.17349 (7)0.4391 (3)0.52416 (6)0.0274 (3)
N20.15351 (7)0.6296 (3)0.46651 (7)0.0286 (3)
C10.11819 (9)0.1146 (3)0.58929 (8)0.0259 (3)
C20.19168 (9)0.0129 (3)0.63240 (8)0.0277 (3)
C30.19421 (10)0.1914 (3)0.68369 (8)0.0322 (3)
H30.24380.25930.71300.039*
C40.12504 (10)0.2958 (3)0.69212 (8)0.0333 (4)
H40.12740.43620.72710.040*
C50.05185 (10)0.1982 (4)0.65017 (9)0.0355 (4)
H50.00440.27180.65610.043*
C60.04881 (9)0.0071 (3)0.59976 (9)0.0326 (4)
H60.00120.07670.57170.039*
C70.11221 (9)0.3247 (3)0.53449 (8)0.0273 (3)
H70.06110.38000.50510.033*
C80.21343 (9)0.7639 (3)0.46080 (8)0.0259 (3)
H80.26370.73700.49580.031*
C90.20573 (8)0.9589 (3)0.40100 (8)0.0248 (3)
C100.13833 (9)0.9571 (3)0.33998 (8)0.0298 (3)
H100.09630.83340.33850.036*
C110.13200 (9)1.1324 (3)0.28202 (8)0.0323 (4)
H110.08601.12860.24090.039*
C120.19294 (9)1.3133 (3)0.28420 (8)0.0314 (3)
H120.18851.43440.24440.038*
C130.26054 (9)1.3203 (3)0.34376 (8)0.0291 (3)
H130.30221.44500.34470.035*
C140.26682 (8)1.1433 (3)0.40201 (8)0.0251 (3)
C150.39957 (9)1.2843 (3)0.46170 (8)0.0312 (3)
H15A0.43641.30160.51170.037*
H15B0.38461.47180.44250.037*
C160.44124 (9)1.1381 (3)0.41393 (8)0.0290 (3)
C170.54618 (11)1.1827 (4)0.36101 (11)0.0423 (4)
H17A0.51141.11050.31420.051*
H17B0.57961.03040.38760.051*
C180.59662 (11)1.4085 (4)0.34751 (11)0.0444 (4)
H18A0.56291.55540.31990.067*
H18B0.63061.33750.31960.067*
H18C0.62971.48140.39420.067*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0279 (6)0.0439 (7)0.0432 (7)0.0035 (5)0.0066 (5)0.0125 (5)
O20.0294 (5)0.0372 (6)0.0291 (5)0.0080 (5)0.0091 (4)0.0026 (5)
O30.0414 (7)0.0279 (6)0.0506 (7)0.0041 (5)0.0164 (5)0.0039 (5)
O40.0364 (6)0.0330 (6)0.0461 (7)0.0077 (5)0.0212 (5)0.0072 (5)
N10.0294 (6)0.0258 (7)0.0276 (6)0.0011 (5)0.0092 (5)0.0035 (5)
N20.0296 (6)0.0270 (7)0.0299 (6)0.0001 (5)0.0101 (5)0.0053 (5)
C10.0290 (7)0.0236 (7)0.0256 (7)0.0023 (6)0.0091 (6)0.0019 (6)
C20.0291 (7)0.0262 (8)0.0270 (7)0.0039 (6)0.0073 (6)0.0035 (6)
C30.0351 (8)0.0310 (8)0.0280 (7)0.0007 (7)0.0058 (6)0.0022 (7)
C40.0459 (9)0.0284 (8)0.0286 (7)0.0006 (7)0.0157 (7)0.0035 (6)
C50.0360 (8)0.0355 (9)0.0405 (9)0.0024 (7)0.0197 (7)0.0038 (7)
C60.0288 (8)0.0336 (9)0.0367 (8)0.0000 (7)0.0119 (6)0.0036 (7)
C70.0259 (7)0.0260 (8)0.0301 (7)0.0004 (6)0.0084 (6)0.0008 (6)
C80.0269 (7)0.0243 (8)0.0278 (7)0.0006 (6)0.0102 (6)0.0002 (6)
C90.0266 (7)0.0222 (7)0.0280 (7)0.0029 (6)0.0121 (6)0.0006 (6)
C100.0265 (7)0.0300 (8)0.0340 (8)0.0003 (6)0.0108 (6)0.0013 (7)
C110.0292 (8)0.0357 (9)0.0308 (8)0.0051 (7)0.0069 (6)0.0045 (7)
C120.0372 (8)0.0286 (8)0.0314 (8)0.0082 (7)0.0147 (6)0.0080 (7)
C130.0333 (8)0.0251 (8)0.0335 (8)0.0007 (6)0.0170 (6)0.0015 (6)
C140.0261 (7)0.0244 (7)0.0272 (7)0.0025 (6)0.0115 (6)0.0007 (6)
C150.0295 (8)0.0331 (9)0.0309 (8)0.0079 (7)0.0090 (6)0.0026 (7)
C160.0275 (7)0.0271 (8)0.0302 (7)0.0022 (6)0.0053 (6)0.0018 (6)
C170.0435 (10)0.0358 (10)0.0562 (11)0.0005 (8)0.0280 (8)0.0050 (8)
C180.0440 (10)0.0438 (11)0.0537 (11)0.0029 (8)0.0273 (8)0.0046 (9)
Geometric parameters (Å, º) top
O1—C21.3548 (18)C8—C91.465 (2)
O1—H1A0.8403C8—H80.9500
O2—C141.3797 (17)C9—C141.400 (2)
O2—C151.4172 (17)C9—C101.401 (2)
O3—C161.2016 (19)C10—C111.381 (2)
O4—C161.3295 (18)C10—H100.9500
O4—C171.4577 (19)C11—C121.382 (2)
N1—C71.2854 (19)C11—H110.9500
N1—N21.4064 (17)C12—C131.387 (2)
N2—C81.2772 (19)C12—H120.9500
C1—C61.402 (2)C13—C141.390 (2)
C1—C21.406 (2)C13—H130.9500
C1—C71.449 (2)C15—C161.515 (2)
C2—C31.391 (2)C15—H15A0.9900
C3—C41.378 (2)C15—H15B0.9900
C3—H30.9500C17—C181.486 (3)
C4—C51.389 (2)C17—H17A0.9900
C4—H40.9500C17—H17B0.9900
C5—C61.381 (2)C18—H18A0.9800
C5—H50.9500C18—H18B0.9800
C6—H60.9500C18—H18C0.9800
C7—H70.9500
C2—O1—H1A101.2C9—C10—H10119.5
C14—O2—C15117.06 (11)C10—C11—C12119.60 (14)
C16—O4—C17117.01 (13)C10—C11—H11120.2
C7—N1—N2112.44 (12)C12—C11—H11120.2
C8—N2—N1112.64 (12)C11—C12—C13120.84 (14)
C6—C1—C2118.59 (14)C11—C12—H12119.6
C6—C1—C7119.35 (14)C13—C12—H12119.6
C2—C1—C7122.06 (13)C12—C13—C14119.45 (14)
O1—C2—C3118.34 (14)C12—C13—H13120.3
O1—C2—C1121.82 (14)C14—C13—H13120.3
C3—C2—C1119.84 (14)O2—C14—C13123.53 (13)
C4—C3—C2120.30 (15)O2—C14—C9115.80 (12)
C4—C3—H3119.9C13—C14—C9120.65 (14)
C2—C3—H3119.9O2—C15—C16111.61 (13)
C3—C4—C5120.80 (15)O2—C15—H15A109.3
C3—C4—H4119.6C16—C15—H15A109.3
C5—C4—H4119.6O2—C15—H15B109.3
C6—C5—C4119.29 (15)C16—C15—H15B109.3
C6—C5—H5120.4H15A—C15—H15B108.0
C4—C5—H5120.4O3—C16—O4124.80 (15)
C5—C6—C1121.17 (15)O3—C16—C15125.22 (14)
C5—C6—H6119.4O4—C16—C15109.98 (13)
C1—C6—H6119.4O4—C17—C18107.37 (14)
N1—C7—C1122.39 (14)O4—C17—H17A110.2
N1—C7—H7118.8C18—C17—H17A110.2
C1—C7—H7118.8O4—C17—H17B110.2
N2—C8—C9120.88 (13)C18—C17—H17B110.2
N2—C8—H8119.6H17A—C17—H17B108.5
C9—C8—H8119.6C17—C18—H18A109.5
C14—C9—C10118.41 (13)C17—C18—H18B109.5
C14—C9—C8120.88 (13)H18A—C18—H18B109.5
C10—C9—C8120.65 (13)C17—C18—H18C109.5
C11—C10—C9121.06 (14)H18A—C18—H18C109.5
C11—C10—H10119.5H18B—C18—H18C109.5
C7—N1—N2—C8173.32 (13)C8—C9—C10—C11177.30 (14)
C6—C1—C2—O1179.77 (14)C9—C10—C11—C120.2 (2)
C7—C1—C2—O10.1 (2)C10—C11—C12—C130.3 (2)
C6—C1—C2—C30.4 (2)C11—C12—C13—C140.2 (2)
C7—C1—C2—C3179.22 (14)C15—O2—C14—C1313.6 (2)
O1—C2—C3—C4178.94 (14)C15—O2—C14—C9168.16 (13)
C1—C2—C3—C40.4 (2)C12—C13—C14—O2178.18 (13)
C2—C3—C4—C50.5 (2)C12—C13—C14—C90.0 (2)
C3—C4—C5—C60.4 (3)C10—C9—C14—O2178.35 (13)
C4—C5—C6—C11.2 (3)C8—C9—C14—O24.28 (19)
C2—C1—C6—C51.3 (2)C10—C9—C14—C130.0 (2)
C7—C1—C6—C5178.39 (15)C8—C9—C14—C13177.39 (13)
N2—N1—C7—C1177.86 (13)C14—O2—C15—C1671.06 (17)
C6—C1—C7—N1177.23 (14)C17—O4—C16—O30.4 (2)
C2—C1—C7—N13.1 (2)C17—O4—C16—C15178.44 (14)
N1—N2—C8—C9175.83 (12)O2—C15—C16—O39.9 (2)
N2—C8—C9—C14167.75 (14)O2—C15—C16—O4171.21 (12)
N2—C8—C9—C1014.9 (2)C16—O4—C17—C18170.82 (14)
C14—C9—C10—C110.1 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···N10.841.852.6441 (17)158
C15—H15A···O4i0.992.583.3568 (19)136
C15—H15B···O3ii0.992.573.440 (2)147
Symmetry codes: (i) x+1, y+3, z+1; (ii) x, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···N10.841.852.6441 (17)158
C15—H15A···O4i0.992.583.3568 (19)136
C15—H15B···O3ii0.992.573.440 (2)147
Symmetry codes: (i) x+1, y+3, z+1; (ii) x, y+1, z.
 

Acknowledgements

The support of NSF–MRI grant No. 1228232 for the purchase of the diffractometer and Tulane University for support of the Tulane Crystallography Laboratory are gratefully acknowledged.

References

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Volume 71| Part 2| February 2015| Pages o70-o71
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