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

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ISSN: 2056-9890

2-Meth­­oxy-4-[(4-methyl­piperazin-1-yl)imino­meth­yl]phenol

aCollege of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, Ninxia, People's Republic of China, and bKey Laboratory of Energy Resource and Chemical Engineering, Yinchuan 750021, Ninxia, People's Republic of China
*Correspondence e-mail: huqilin@nxu.edu.cn

(Received 1 December 2010; accepted 6 December 2010; online 11 December 2010)

The title compound, C13H19N3O2, was obtained by the direct solvent-free reaction of 4-hy­droxy-3-meth­oxy­benzaldehyde with 1-amino-4-methyl­piperazine. The piperazine ring adopts a chair conformation. In the crystal, strong inter­molecular O—H⋯N and weak inter­molecular C—H⋯O and C—H⋯N hydrogen bonds help to establish the packing.

Related literature

For the biological properties of piperazine compounds, see: Obniska et al. (2005[Obniska, J., Jurczyk, S., Zejc, A., Kamiński, K., Tatarczyńska, E. & Stachowicz, K. (2005). Pharmacol. Rep. 57, 170-175.]); Smid et al. (2005[Smid, P., Coolen, H. K. A. C., Keizer, H. G., van Hes, R., de Moes, J.-P., den Hartog, A. P., Stork, B., Plekkenpol, R. H., Niemann, L. C., Stroomer, C. N. J., Tulp, M. Th. M., van Stuivenberg, H. H., McCreary, A. C., Hesselink, M. B., Herremans, A. H. J. & Kruse, C. G. (2005). J. Med. Chem. 48, 6855-6869.]). For background and related structures, see: Guo (2004[Guo, M.-L. (2004). Acta Cryst. E60, o574-o575.], 2007[Guo, M.-L. (2007). Acta Cryst. E63, o1788-o1789.]).

[Scheme 1]

Experimental

Crystal data
  • C13H19N3O2

  • Mr = 249.31

  • Orthorhombic, P n a 21

  • a = 12.179 (2) Å

  • b = 18.624 (3) Å

  • c = 6.0187 (10) Å

  • V = 1365.1 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 296 K

  • 0.25 × 0.25 × 0.10 mm

Data collection
  • Siemens SMART CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2002[Bruker (2002). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.642, Tmax = 0.745

  • 7503 measured reflections

  • 1582 independent reflections

  • 1126 reflections with I > 2σ(I)

  • Rint = 0.043

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.077

  • S = 1.01

  • 1582 reflections

  • 169 parameters

  • 1 restraint

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

  • Δρmax = 0.13 e Å−3

  • Δρmin = −0.13 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯N2i 0.94 (4) 1.88 (4) 2.734 (3) 151 (3)
C11—H11A⋯O2ii 0.96 2.67 3.311 (4) 125
C5—H5⋯N1iii 0.93 2.67 3.460 (4) 143
Symmetry codes: (i) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, z-{\script{1\over 2}}]; (iii) [-x, -y+1, z-{\script{1\over 2}}].

Data collection: SMART (Bruker, 2007[Bruker (2007). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: DIAMOND (Brandenburg, 1999)[Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.]; software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Piperazine and it's derivatives are important targets for drug discovery. For the biological properties of piperazine compounds, see: Obniska et al. (2005); Smid et al. (2005). For background of this study and related structures, see: Guo (2004); Guo (2007).

The title compound, (I), is a hydrazone in which 4-hydroxy-3-methoxy-benzaldehyde has reacted directly with 1-amino-4-methylpiperazine to form a product containing the C=N double bond. The structure of the compound is shown in Fig. 1. The C=N double bond shows an E configuration and is effectively coplanar with the benzene ring [N3–C8–C6–C7=1.6 (5)°]. The piperazine ring exhibits a chair conformation. The bond distances and angles are normal. In the crystal structure, strong intermolecular N—H···O and weak intermolecular C—H···O and C—H···N hydrogen bonds (see Table 1 for symmetry code) and van der Waals forces are responsible for the observed packing motif. A packing diagram for (I) is shown in Fig. 2.

Related literature top

For the biological properties of piperazine compounds, see: Obniska et al. (2005); Smid et al. (2005). For background and related structures, see: Guo (2004, 2007).

Experimental top

The title compound was prepared by the direct solvent-free reaction of 4-hydroxy-3-methoxy-benzaldehyde (1.52 g) with 1-amino-4-methylpiperazine (1.15 g) with stirring at 351 K for 30 min. The resulting product was dissolved in ethanol (10 ml) with heating. The homogeneous solution was allowed to stand at room temperature for 12 h, after which the crystalline product was separated by filtration (yield 2.0 g, 80%). The pure product (0.5 g) was dissolved in hot ethanol (20 ml). Single crystals were obtained from this solution by slow evaporation over a period of 7 d at room temperature.

Refinement top

In the absence of significant anomalous dispersion effects Friedel pairs have been merged. All H atoms were positioned geometrically and refined using the riding-model approximation, with C—H = 0.93 or 0.96 Å, O—H = 0.82 Å, N—H = 0.86 Å and Uiso(H) = 1.2Ueq(C, N) or Uiso(H) = 1.5Ueq(methyl C and O).

Structure description top

Piperazine and it's derivatives are important targets for drug discovery. For the biological properties of piperazine compounds, see: Obniska et al. (2005); Smid et al. (2005). For background of this study and related structures, see: Guo (2004); Guo (2007).

The title compound, (I), is a hydrazone in which 4-hydroxy-3-methoxy-benzaldehyde has reacted directly with 1-amino-4-methylpiperazine to form a product containing the C=N double bond. The structure of the compound is shown in Fig. 1. The C=N double bond shows an E configuration and is effectively coplanar with the benzene ring [N3–C8–C6–C7=1.6 (5)°]. The piperazine ring exhibits a chair conformation. The bond distances and angles are normal. In the crystal structure, strong intermolecular N—H···O and weak intermolecular C—H···O and C—H···N hydrogen bonds (see Table 1 for symmetry code) and van der Waals forces are responsible for the observed packing motif. A packing diagram for (I) is shown in Fig. 2.

For the biological properties of piperazine compounds, see: Obniska et al. (2005); Smid et al. (2005). For background and related structures, see: Guo (2004, 2007).

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (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: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound, showing 30% displacement ellipsoids for non-hydrogen atoms. Hydrogen atoms are drawn as spheres of arbitrary radius.
[Figure 2] Fig. 2. Molecular packing of the title compound, viewed along the c axis. Hydrogen bonds are shown as dashed lines.
2-Methoxy-4-[(4-methylpiperazin-1-yl)iminomethyl]phenol top
Crystal data top
C13H19N3O2Dx = 1.213 Mg m3
Mr = 249.31Melting point: not measured K
Orthorhombic, Pna21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2nCell parameters from 1708 reflections
a = 12.179 (2) Åθ = 2.0–25.1°
b = 18.624 (3) ŵ = 0.08 mm1
c = 6.0187 (10) ÅT = 296 K
V = 1365.1 (4) Å3Club-shaped, colorless
Z = 40.25 × 0.25 × 0.10 mm
F(000) = 536
Data collection top
Siemens SMART CCD
diffractometer
1582 independent reflections
Radiation source: fine-focus sealed tube1126 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.043
Detector resolution: 9.00 cm pixels mm-1θmax = 26.7°, θmin = 2.0°
ω scansh = 1514
Absorption correction: multi-scan
(SADABS; Bruker, 2002)
k = 2321
Tmin = 0.642, Tmax = 0.745l = 76
7503 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.040H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.077 w = 1/[σ2(Fo2) + (0.010P)2 + 0.480P]
where P = (Fo2 + 2Fc2)/3
S = 1.01(Δ/σ)max < 0.001
1582 reflectionsΔρmax = 0.13 e Å3
169 parametersΔρmin = 0.13 e Å3
1 restraintExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0157 (12)
Crystal data top
C13H19N3O2V = 1365.1 (4) Å3
Mr = 249.31Z = 4
Orthorhombic, Pna21Mo Kα radiation
a = 12.179 (2) ŵ = 0.08 mm1
b = 18.624 (3) ÅT = 296 K
c = 6.0187 (10) Å0.25 × 0.25 × 0.10 mm
Data collection top
Siemens SMART CCD
diffractometer
1582 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2002)
1126 reflections with I > 2σ(I)
Tmin = 0.642, Tmax = 0.745Rint = 0.043
7503 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0401 restraint
wR(F2) = 0.077H atoms treated by a mixture of independent and constrained refinement
S = 1.01Δρmax = 0.13 e Å3
1582 reflectionsΔρmin = 0.13 e Å3
169 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
O10.38591 (18)0.68018 (10)0.1639 (4)0.0597 (7)
H10.440 (3)0.6712 (18)0.271 (7)0.090*
O20.39131 (16)0.56755 (10)0.4468 (4)0.0563 (6)
N10.02060 (18)0.33961 (11)0.1024 (4)0.0441 (6)
N20.05455 (17)0.20217 (11)0.0440 (5)0.0459 (6)
N30.09346 (17)0.39555 (11)0.1421 (5)0.0460 (6)
C10.3972 (3)0.50737 (15)0.5919 (6)0.0621 (9)
H1A0.32910.50250.67070.093*
H1B0.45600.51430.69610.093*
H1C0.41070.46470.50680.093*
C20.3147 (2)0.56473 (14)0.2784 (5)0.0406 (7)
C30.3161 (2)0.62428 (13)0.1367 (5)0.0433 (7)
C40.2429 (2)0.62631 (14)0.0381 (6)0.0500 (7)
H40.24280.66560.13360.060*
C50.1695 (2)0.57068 (14)0.0731 (6)0.0491 (8)
H50.12020.57330.19080.059*
C60.1687 (2)0.51122 (14)0.0650 (5)0.0429 (7)
C70.2418 (2)0.50933 (14)0.2442 (5)0.0439 (7)
H70.24120.47040.34080.053*
C80.0937 (2)0.45134 (14)0.0184 (6)0.0478 (8)
H8A0.04710.45510.11550.057*
C90.0658 (2)0.27338 (13)0.1924 (6)0.0517 (8)
H9A0.08870.28120.34490.062*
H9B0.12990.25940.10700.062*
C100.0186 (2)0.21406 (15)0.1845 (6)0.0518 (8)
H10A0.01290.17020.24350.062*
H10B0.08120.22700.27590.062*
C110.1364 (2)0.14440 (14)0.0515 (7)0.0655 (10)
H11A0.10340.10030.00320.098*
H11B0.16280.13900.20090.098*
H11C0.19670.15620.04460.098*
C120.1020 (2)0.26857 (13)0.1319 (6)0.0524 (9)
H12A0.16670.28100.04610.063*
H12B0.12470.26090.28450.063*
C130.0210 (2)0.33023 (15)0.1233 (6)0.0500 (9)
H13A0.03980.32060.22330.060*
H13B0.05670.37410.17180.060*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0704 (15)0.0501 (12)0.0588 (16)0.0206 (11)0.0153 (13)0.0126 (12)
O20.0664 (13)0.0492 (11)0.0535 (14)0.0121 (10)0.0184 (14)0.0125 (12)
N10.0432 (13)0.0371 (12)0.0519 (17)0.0026 (10)0.0032 (13)0.0023 (12)
N20.0443 (12)0.0383 (12)0.0550 (17)0.0042 (10)0.0015 (14)0.0058 (14)
N30.0453 (13)0.0377 (12)0.0549 (17)0.0026 (11)0.0025 (13)0.0054 (13)
C10.075 (2)0.0572 (18)0.054 (2)0.0014 (16)0.013 (2)0.0147 (18)
C20.0438 (16)0.0369 (15)0.0410 (17)0.0015 (12)0.0031 (14)0.0023 (14)
C30.0462 (16)0.0365 (15)0.0473 (19)0.0047 (12)0.0008 (15)0.0041 (16)
C40.0592 (18)0.0406 (15)0.0502 (19)0.0013 (14)0.0062 (18)0.0078 (17)
C50.0479 (16)0.0477 (16)0.052 (2)0.0020 (14)0.0128 (17)0.0035 (16)
C60.0377 (15)0.0378 (14)0.053 (2)0.0014 (12)0.0004 (14)0.0016 (14)
C70.0460 (16)0.0352 (14)0.051 (2)0.0021 (13)0.0013 (16)0.0065 (14)
C80.0420 (16)0.0428 (15)0.059 (2)0.0007 (13)0.0032 (15)0.0021 (15)
C90.0599 (18)0.0465 (16)0.049 (2)0.0022 (14)0.0068 (16)0.0026 (16)
C100.0581 (19)0.0421 (16)0.055 (2)0.0050 (14)0.0064 (17)0.0006 (16)
C110.0586 (19)0.0456 (16)0.092 (3)0.0088 (14)0.001 (2)0.008 (2)
C120.0487 (17)0.0434 (16)0.065 (2)0.0024 (14)0.0094 (15)0.0078 (16)
C130.0531 (18)0.0421 (17)0.055 (2)0.0010 (14)0.0105 (16)0.0010 (15)
Geometric parameters (Å, º) top
O1—C31.354 (3)C5—C61.385 (4)
O1—H10.94 (4)C5—H50.9300
O2—C21.378 (3)C6—C71.399 (4)
O2—C11.423 (3)C6—C81.468 (4)
N1—N31.389 (3)C7—H70.9300
N1—C91.456 (3)C8—H8A0.9884
N1—C131.460 (4)C9—C101.510 (4)
N2—C101.460 (4)C9—H9A0.9700
N2—C121.464 (3)C9—H9B0.9700
N2—C111.468 (3)C10—H10A0.9700
N3—C81.278 (3)C10—H10B0.9700
C1—H1A0.9600C11—H11A0.9600
C1—H1B0.9600C11—H11B0.9600
C1—H1C0.9600C11—H11C0.9600
C2—C71.377 (4)C12—C131.515 (4)
C2—C31.399 (4)C12—H12A0.9700
C3—C41.380 (4)C12—H12B0.9700
C4—C51.384 (3)C13—H13A0.9700
C4—H40.9300C13—H13B0.9700
C3—O1—H1113 (2)N3—C8—C6120.5 (3)
C2—O2—C1117.1 (2)N3—C8—H8A122.1
N3—N1—C9109.2 (2)C6—C8—H8A117.3
N3—N1—C13118.1 (2)N1—C9—C10110.5 (2)
C9—N1—C13112.1 (2)N1—C9—H9A109.5
C10—N2—C12109.3 (2)C10—C9—H9A109.5
C10—N2—C11110.1 (3)N1—C9—H9B109.5
C12—N2—C11109.9 (2)C10—C9—H9B109.5
C8—N3—N1120.7 (2)H9A—C9—H9B108.1
O2—C1—H1A109.5N2—C10—C9110.2 (3)
O2—C1—H1B109.5N2—C10—H10A109.6
H1A—C1—H1B109.5C9—C10—H10A109.6
O2—C1—H1C109.5N2—C10—H10B109.6
H1A—C1—H1C109.5C9—C10—H10B109.6
H1B—C1—H1C109.5H10A—C10—H10B108.1
C7—C2—O2125.1 (3)N2—C11—H11A109.5
C7—C2—C3120.7 (3)N2—C11—H11B109.5
O2—C2—C3114.2 (2)H11A—C11—H11B109.5
O1—C3—C4118.5 (3)N2—C11—H11C109.5
O1—C3—C2122.9 (3)H11A—C11—H11C109.5
C4—C3—C2118.6 (2)H11B—C11—H11C109.5
C3—C4—C5120.9 (3)N2—C12—C13111.8 (2)
C3—C4—H4119.6N2—C12—H12A109.3
C5—C4—H4119.6C13—C12—H12A109.3
C4—C5—C6120.8 (3)N2—C12—H12B109.3
C4—C5—H5119.6C13—C12—H12B109.3
C6—C5—H5119.6H12A—C12—H12B107.9
C5—C6—C7118.6 (3)N1—C13—C12110.4 (3)
C5—C6—C8119.9 (3)N1—C13—H13A109.6
C7—C6—C8121.6 (3)C12—C13—H13A109.6
C2—C7—C6120.5 (3)N1—C13—H13B109.6
C2—C7—H7119.8C12—C13—H13B109.6
C6—C7—H7119.8H13A—C13—H13B108.1
C9—N1—N3—C8155.1 (3)C5—C6—C7—C21.6 (4)
C13—N1—N3—C825.5 (4)C8—C6—C7—C2177.0 (3)
C1—O2—C2—C72.0 (4)N1—N3—C8—C6178.2 (2)
C1—O2—C2—C3177.6 (3)C5—C6—C8—N3178.7 (3)
C7—C2—C3—O1179.7 (3)C7—C6—C8—N30.1 (4)
O2—C2—C3—O10.7 (4)N3—N1—C9—C10171.1 (3)
C7—C2—C3—C40.0 (4)C13—N1—C9—C1056.0 (3)
O2—C2—C3—C4179.6 (3)C12—N2—C10—C959.3 (3)
O1—C3—C4—C5179.8 (3)C11—N2—C10—C9179.9 (2)
C2—C3—C4—C50.1 (4)N1—C9—C10—N258.7 (3)
C3—C4—C5—C60.7 (5)C10—N2—C12—C1358.0 (3)
C4—C5—C6—C71.5 (4)C11—N2—C12—C13178.9 (3)
C4—C5—C6—C8177.1 (3)N3—N1—C13—C12177.9 (2)
O2—C2—C7—C6178.7 (3)C9—N1—C13—C1253.7 (3)
C3—C2—C7—C60.8 (4)N2—C12—C13—N154.9 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N2i0.94 (4)1.88 (4)2.734 (3)151 (3)
C11—H11A···O2ii0.962.673.311 (4)125
C5—H5···N1iii0.932.673.460 (4)143
Symmetry codes: (i) x+1/2, y+1/2, z+1/2; (ii) x+1/2, y1/2, z1/2; (iii) x, y+1, z1/2.

Experimental details

Crystal data
Chemical formulaC13H19N3O2
Mr249.31
Crystal system, space groupOrthorhombic, Pna21
Temperature (K)296
a, b, c (Å)12.179 (2), 18.624 (3), 6.0187 (10)
V3)1365.1 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.25 × 0.25 × 0.10
Data collection
DiffractometerSiemens SMART CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2002)
Tmin, Tmax0.642, 0.745
No. of measured, independent and
observed [I > 2σ(I)] reflections
7503, 1582, 1126
Rint0.043
(sin θ/λ)max1)0.632
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.077, 1.01
No. of reflections1582
No. of parameters169
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.13, 0.13

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N2i0.94 (4)1.88 (4)2.734 (3)151 (3)
C11—H11A···O2ii0.962.673.311 (4)124.5
C5—H5···N1iii0.932.673.460 (4)143.3
Symmetry codes: (i) x+1/2, y+1/2, z+1/2; (ii) x+1/2, y1/2, z1/2; (iii) x, y+1, z1/2.
 

Acknowledgements

We thank the Instrumental Analysis Center of Northwest University for the data collection on the CCD facility.

References

First citationBrandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
First citationBruker (2002). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationBruker (2007). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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