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

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ISSN: 2056-9890

2,4-Dihydr­­oxy-N′-(3,4,5-tri­meth­oxy­benzyl­­idene)benzohydrazide

aCollege of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian 116000, People's Republic of China, and bDalian Medical University, Dalian 116044, People's Republic of China
*Correspondence e-mail: dlzhanghouli@163.com

(Received 2 September 2009; accepted 4 September 2009; online 9 September 2009)

In the title compound, C17H18N2O6, the mol­ecule is slightly twisted, with a dihedral angle of 18.1 (2)° between the two benzene rings. In the crystal structure, mol­ecules are linked into a network by inter­molecular N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds. An intra­molecular O—H⋯O hydrogen bond is also present.

Related literature

For the biological properties of Schiff base compounds, see: Brückner et al. (2000[Brückner, C., Rettig, S. J. & Dolphin, D. (2000). Inorg. Chem. 39, 6100-6106.]); Harrop et al. (2003[Harrop, T. C., Olmstead, M. M. & Mascharak, P. K. (2003). Chem. Commun. pp. 410-411.]); Ren et al. (2002[Ren, S., Wang, R., Komatsu, K., Bonaz-Krause, P., Zyrianov, Y., McKenna, C. E., Csipke, C., Tokes, Z. A. & Lien, E. J. (2002). J. Med. Chem. 45, 410-419.]). For the crystal structures of some Schiff bases and their complexes, see: Diao (2007[Diao, Y.-P. (2007). Acta Cryst. E63, m1453-m1454.]); Diao et al. (2007[Diao, Y.-P., Shu, X.-H., Zhang, B.-J., Zhen, Y.-H. & Kang, T.-G. (2007). Acta Cryst. E63, m1816.], 2008[Diao, Y.-P., Zhen, Y.-H., Han, X. & Deng, S. (2008). Acta Cryst. E64, o101.]); Huang et al. (2007[Huang, S.-S., Zhou, Q. & Diao, Y.-P. (2007). Acta Cryst. E63, o4659.]); Li et al. (2007[Li, K., Huang, S.-S., Zhang, B.-J., Meng, D.-L. & Diao, Y.-P. (2007). Acta Cryst. E63, m2291.]).

[Scheme 1]

Experimental

Crystal data
  • C17H18N2O6

  • Mr = 346.33

  • Orthorhombic, P b c a

  • a = 14.601 (1) Å

  • b = 11.030 (2) Å

  • c = 20.006 (2) Å

  • V = 3222.0 (7) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 298 K

  • 0.20 × 0.20 × 0.20 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2000[Bruker (2000). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.978, Tmax = 0.978

  • 18590 measured reflections

  • 3520 independent reflections

  • 2166 reflections with I > 2σ(I)

  • Rint = 0.069

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.148

  • S = 1.03

  • 3520 reflections

  • 234 parameters

  • 1 restraint

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.41 e Å−3

  • Δρmin = −0.24 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1A⋯O5i 0.893 (10) 2.109 (13) 2.953 (2) 157 (2)
O3—H3⋯N2ii 0.82 2.52 3.214 (3) 143
O3—H3⋯O1ii 0.82 1.95 2.674 (2) 147
O2—H2⋯O1 0.82 1.79 2.518 (2) 147
Symmetry codes: (i) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]; (ii) [x-{\script{1\over 2}}, y, -z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 2000[Bruker (2000). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2000[Bruker (2000). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Schiff base compounds have been found to have potential pharmacological and antitumor properties (Brückner et al., 2000; Harrop et al., 2003; Ren et al., 2002). Recently, the crystal structures of a few Schiff base compounds derived from the reaction of aldehydes with benzohydrazides have been reported (Diao et al., 2008; Diao et al., 2007; Diao, 2007; Li et al., 2007; Huang et al., 2007). As a continuation of these studies, we report here the crystal structure of the title compound.

The title compound, C17H18N2O6 (Fig. 1) is slightly twisted, with a dihedral angle between the two benzene rings of 18.1 (2)°. The torsion angles C9—C8—N2—N1 and C2—C7—N1—N2 are 2.9 (2) and 7.8 (2)°, respectively. In the crystal structure, molecules are linked into a network (Fig. 2) by intermolecular N—H···O, O—H···N and O—H···O hydrogen bonds (Table 1). An intramolecular O—H···O hydrogen bond is also present.

Related literature top

For the biological properties of Schiff base compounds, see: Brückner et al. (2000); Harrop et al. (2003); Ren et al. (2002). For the crystal structures of some Schiff bases and their complexes, see: Diao (2007); Diao et al. (2007, 2008); Huang et al. (2007); Li et al. (2007).

Experimental top

3,4,5-Trimethoxybenzaldehyde (0.1 mmol, 19.6 mg) and 2,4-dihydroxybenzohydrazide (0.1 mmol, 16.8 mg) were dissolved in a methanol solution (20 ml). The mixture was stirred at reflux for 1 h and cooled to room temperature. After allowing the solution to stand in air for a few days, colorless block-like crystals were formed.

Refinement top

H1A was located in a difference Fourier map and refined isotropically, with the N—H distance restrained to 0.90 (1) Å. Other H atoms were placed in calculated positions and constrained to ride on their parent atoms, with C—H distances of 0.93 and 0.96 Å, an O—H distance of 0.82 Å, and with Uiso(H) = 1.2Ueq(aromatic C) and 1.5Ueq(O and methyl C).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level. Hydrogen atoms are represented by spheres of arbitrary radius. The dashed line indicates the intramolecular O—H···O hydrogen bond.
[Figure 2] Fig. 2. The crystal structure of the title compound, viewed along the b axis. Dashed lines indicate hydrogen bonds. Hydrogen atoms not involved in hydrogen bonding have been omitted.
2,4-Dihydroxy-N'-(3,4,5-trimethoxybenzylidene)benzohydrazide top
Crystal data top
C17H18N2O6F(000) = 1456
Mr = 346.33Dx = 1.428 Mg m3
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 2734 reflections
a = 14.601 (1) Åθ = 2.5–26.0°
b = 11.030 (2) ŵ = 0.11 mm1
c = 20.006 (2) ÅT = 298 K
V = 3222.0 (7) Å3Block, colorless
Z = 80.20 × 0.20 × 0.20 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
3520 independent reflections
Radiation source: fine-focus sealed tube2166 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.069
ω scansθmax = 27.0°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
h = 1818
Tmin = 0.978, Tmax = 0.978k = 1214
18590 measured reflectionsl = 2025
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)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.148H atoms treated by a mixture of independent and constrained refinement
S = 1.03 w = 1/[σ2(Fo2) + (0.0632P)2 + 0.9796P]
where P = (Fo2 + 2Fc2)/3
3520 reflections(Δ/σ)max = 0.001
234 parametersΔρmax = 0.41 e Å3
1 restraintΔρmin = 0.24 e Å3
Crystal data top
C17H18N2O6V = 3222.0 (7) Å3
Mr = 346.33Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 14.601 (1) ŵ = 0.11 mm1
b = 11.030 (2) ÅT = 298 K
c = 20.006 (2) Å0.20 × 0.20 × 0.20 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
3520 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
2166 reflections with I > 2σ(I)
Tmin = 0.978, Tmax = 0.978Rint = 0.069
18590 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0481 restraint
wR(F2) = 0.148H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.41 e Å3
3520 reflectionsΔρmin = 0.24 e Å3
234 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
xyzUiso*/Ueq
N10.07006 (12)0.46657 (17)0.36310 (9)0.0409 (5)
N20.00500 (12)0.44220 (16)0.40282 (9)0.0410 (4)
O10.01502 (10)0.60011 (16)0.30628 (8)0.0528 (5)
O20.04899 (12)0.72863 (18)0.21335 (9)0.0650 (5)
H20.01120.70570.24090.097*
O30.33269 (11)0.63390 (17)0.12189 (8)0.0555 (5)
H30.38140.60180.13220.083*
O40.12167 (11)0.13843 (16)0.63808 (9)0.0584 (5)
O50.28830 (10)0.21803 (14)0.60976 (8)0.0474 (4)
O60.31779 (11)0.37901 (16)0.51322 (9)0.0579 (5)
C10.21013 (15)0.4894 (2)0.25893 (12)0.0420 (5)
H10.21690.42510.28860.050*
C20.13151 (14)0.56173 (19)0.26278 (11)0.0384 (5)
C30.12280 (15)0.6558 (2)0.21550 (11)0.0431 (5)
C40.19085 (16)0.6778 (2)0.16936 (12)0.0465 (6)
H40.18430.74080.13880.056*
C50.26856 (15)0.6071 (2)0.16830 (11)0.0418 (5)
C60.27758 (15)0.5110 (2)0.21243 (11)0.0421 (5)
H60.32900.46130.21060.050*
C70.05838 (14)0.54391 (19)0.31173 (11)0.0396 (5)
C80.00724 (15)0.3683 (2)0.45107 (11)0.0423 (5)
H80.06520.33660.45930.051*
C90.07007 (15)0.33347 (19)0.49349 (11)0.0402 (5)
C100.15711 (15)0.3793 (2)0.48163 (11)0.0435 (5)
H100.16650.43510.44750.052*
C110.22944 (15)0.3418 (2)0.52056 (12)0.0437 (6)
C120.21532 (15)0.2592 (2)0.57258 (11)0.0411 (5)
C130.12835 (16)0.2157 (2)0.58524 (11)0.0428 (5)
C140.05539 (15)0.2521 (2)0.54515 (11)0.0428 (5)
H140.00310.22190.55300.051*
C150.33483 (18)0.4696 (3)0.46434 (14)0.0652 (8)
H15A0.32420.43670.42060.098*
H15B0.39730.49620.46770.098*
H15C0.29460.53710.47170.098*
C160.3270 (2)0.3053 (2)0.65403 (14)0.0655 (8)
H16A0.31950.38500.63550.098*
H16B0.39100.28870.65990.098*
H16C0.29660.30100.69650.098*
C170.03536 (19)0.0858 (3)0.65186 (14)0.0646 (8)
H17A0.00980.14860.65600.097*
H17B0.03870.04080.69290.097*
H17C0.01860.03230.61600.097*
H1A0.1231 (10)0.4289 (19)0.3709 (11)0.050*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0320 (10)0.0498 (11)0.0407 (11)0.0008 (8)0.0063 (8)0.0046 (8)
N20.0349 (10)0.0496 (10)0.0385 (11)0.0046 (8)0.0062 (8)0.0037 (9)
O10.0353 (9)0.0687 (11)0.0544 (11)0.0083 (8)0.0044 (8)0.0092 (8)
O20.0514 (11)0.0832 (13)0.0603 (12)0.0237 (10)0.0062 (8)0.0223 (10)
O30.0411 (9)0.0797 (12)0.0457 (10)0.0056 (9)0.0069 (8)0.0135 (9)
O40.0475 (10)0.0716 (11)0.0561 (11)0.0065 (8)0.0100 (8)0.0231 (9)
O50.0397 (9)0.0548 (9)0.0477 (10)0.0062 (7)0.0115 (7)0.0020 (8)
O60.0359 (9)0.0830 (12)0.0548 (11)0.0034 (8)0.0009 (8)0.0142 (9)
C10.0383 (12)0.0432 (12)0.0445 (13)0.0004 (9)0.0003 (10)0.0051 (10)
C20.0321 (11)0.0461 (12)0.0371 (12)0.0001 (9)0.0016 (9)0.0015 (10)
C30.0340 (12)0.0543 (13)0.0411 (13)0.0075 (10)0.0014 (10)0.0021 (11)
C40.0445 (14)0.0559 (14)0.0391 (13)0.0046 (11)0.0008 (10)0.0104 (11)
C50.0347 (12)0.0586 (14)0.0320 (12)0.0022 (10)0.0010 (9)0.0001 (10)
C60.0349 (12)0.0469 (12)0.0444 (13)0.0044 (10)0.0017 (10)0.0005 (11)
C70.0305 (11)0.0465 (12)0.0417 (13)0.0004 (9)0.0013 (9)0.0037 (10)
C80.0350 (12)0.0497 (13)0.0423 (13)0.0002 (10)0.0053 (10)0.0020 (11)
C90.0368 (12)0.0463 (12)0.0374 (13)0.0027 (9)0.0051 (10)0.0036 (10)
C100.0419 (13)0.0529 (13)0.0356 (12)0.0032 (10)0.0025 (10)0.0037 (10)
C110.0326 (12)0.0558 (14)0.0427 (13)0.0010 (10)0.0004 (10)0.0020 (11)
C120.0354 (12)0.0479 (12)0.0399 (13)0.0062 (10)0.0062 (10)0.0028 (10)
C130.0437 (13)0.0464 (12)0.0382 (13)0.0023 (10)0.0032 (10)0.0016 (10)
C140.0338 (12)0.0519 (13)0.0428 (13)0.0014 (10)0.0033 (10)0.0012 (11)
C150.0477 (16)0.0815 (19)0.0664 (18)0.0079 (13)0.0057 (14)0.0125 (15)
C160.0667 (18)0.0671 (17)0.0629 (18)0.0099 (14)0.0232 (15)0.0177 (14)
C170.0556 (16)0.0703 (17)0.0678 (18)0.0114 (14)0.0058 (14)0.0237 (14)
Geometric parameters (Å, º) top
N1—C71.346 (3)C4—H40.9300
N1—N21.380 (2)C5—C61.386 (3)
N1—H1A0.893 (10)C6—H60.9300
N2—C81.276 (3)C8—C91.464 (3)
O1—C71.243 (2)C8—H80.9300
O2—C31.345 (3)C9—C141.385 (3)
O2—H20.8200C9—C101.388 (3)
O3—C51.351 (3)C10—C111.376 (3)
O3—H30.8200C10—H100.9300
O4—C131.362 (3)C11—C121.399 (3)
O4—C171.415 (3)C12—C131.381 (3)
O5—C121.376 (2)C13—C141.393 (3)
O5—C161.425 (3)C14—H140.9300
O6—C111.362 (3)C15—H15A0.9600
O6—C151.420 (3)C15—H15B0.9600
C1—C61.375 (3)C15—H15C0.9600
C1—C21.400 (3)C16—H16A0.9600
C1—H10.9300C16—H16B0.9600
C2—C31.410 (3)C16—H16C0.9600
C2—C71.462 (3)C17—H17A0.9600
C3—C41.378 (3)C17—H17B0.9600
C4—C51.377 (3)C17—H17C0.9600
C7—N1—N2117.54 (17)C10—C9—C8120.8 (2)
C7—N1—H1A122.6 (15)C11—C10—C9119.8 (2)
N2—N1—H1A119.8 (15)C11—C10—H10120.1
C8—N2—N1116.67 (18)C9—C10—H10120.1
C3—O2—H2109.5O6—C11—C10125.2 (2)
C5—O3—H3109.5O6—C11—C12114.60 (19)
C13—O4—C17118.17 (18)C10—C11—C12120.2 (2)
C12—O5—C16114.84 (18)O5—C12—C13119.9 (2)
C11—O6—C15116.89 (19)O5—C12—C11120.2 (2)
C6—C1—C2121.7 (2)C13—C12—C11119.9 (2)
C6—C1—H1119.1O4—C13—C12115.19 (19)
C2—C1—H1119.1O4—C13—C14124.9 (2)
C1—C2—C3117.1 (2)C12—C13—C14119.9 (2)
C1—C2—C7124.0 (2)C9—C14—C13119.9 (2)
C3—C2—C7118.85 (19)C9—C14—H14120.1
O2—C3—C4116.8 (2)C13—C14—H14120.1
O2—C3—C2122.2 (2)O6—C15—H15A109.5
C4—C3—C2121.0 (2)O6—C15—H15B109.5
C5—C4—C3120.3 (2)H15A—C15—H15B109.5
C5—C4—H4119.8O6—C15—H15C109.5
C3—C4—H4119.8H15A—C15—H15C109.5
O3—C5—C4117.2 (2)H15B—C15—H15C109.5
O3—C5—C6122.6 (2)O5—C16—H16A109.5
C4—C5—C6120.1 (2)O5—C16—H16B109.5
C1—C6—C5119.7 (2)H16A—C16—H16B109.5
C1—C6—H6120.2O5—C16—H16C109.5
C5—C6—H6120.2H16A—C16—H16C109.5
O1—C7—N1119.5 (2)H16B—C16—H16C109.5
O1—C7—C2120.3 (2)O4—C17—H17A109.5
N1—C7—C2120.25 (19)O4—C17—H17B109.5
N2—C8—C9119.9 (2)H17A—C17—H17B109.5
N2—C8—H8120.1O4—C17—H17C109.5
C9—C8—H8120.1H17A—C17—H17C109.5
C14—C9—C10120.3 (2)H17B—C17—H17C109.5
C14—C9—C8118.9 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O5i0.89 (1)2.11 (1)2.953 (2)157 (2)
O3—H3···N2ii0.822.523.214 (3)143
O3—H3···O1ii0.821.952.674 (2)147
O2—H2···O10.821.792.518 (2)147
Symmetry codes: (i) x1/2, y+1/2, z+1; (ii) x1/2, y, z+1/2.

Experimental details

Crystal data
Chemical formulaC17H18N2O6
Mr346.33
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)298
a, b, c (Å)14.601 (1), 11.030 (2), 20.006 (2)
V3)3222.0 (7)
Z8
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.20 × 0.20 × 0.20
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2000)
Tmin, Tmax0.978, 0.978
No. of measured, independent and
observed [I > 2σ(I)] reflections
18590, 3520, 2166
Rint0.069
(sin θ/λ)max1)0.639
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.148, 1.03
No. of reflections3520
No. of parameters234
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.41, 0.24

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O5i0.893 (10)2.109 (13)2.953 (2)157 (2)
O3—H3···N2ii0.822.523.214 (3)143.4
O3—H3···O1ii0.821.952.674 (2)146.6
O2—H2···O10.821.792.518 (2)146.6
Symmetry codes: (i) x1/2, y+1/2, z+1; (ii) x1/2, y, z+1/2.
 

Acknowledgements

This project is supported by a research grant from Dalian Medical University. We are grateful to Chuan-Xun Li and Qi Zhou for their assistance.

References

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