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

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ISSN: 2056-9890

3-[2-(3-Phenyl-2-oxo-1,2-di­hydro­quin­oxalin-1-yl)eth­yl]-1,3-oxazolidin-2-one

aLaboratoire de Chimie Organique Hétérocyclique URAC 21, Pôle de Compétences, Pharmacochimie, Avenue Ibn Battouta, BP 1014, Faculté des Sciences, Université Mohammed V-Agdal, Rabat, Morocco, and bLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Battouta, BP 1014, Rabat, Morocco
*Correspondence e-mail: bal_daouda@yahoo.fr

(Received 25 March 2013; accepted 29 March 2013; online 5 April 2013)

The di­hydro­quinoxaline ring system of the title mol­ecule, C19H17N3O3, is approximately planar [maximum deviation = 0.050 (2) Å], the dihedral angle between the planes through the two fused rings being 4.75 (8)°. The mean plane through the fused-ring system forms a dihedral angle of 30.72 (5)° with the attached phenyl ring. The mol­ecular conformation is enforced by C—H⋯O hydrogen bonds. In the crystal, mol­ecules are linked by weak C—H⋯O hydrogen bonds, forming a three-dimensional network.

Related literature

For biochemical properties of quinoxaline derivatives, see: Seitz et al. (2002[Seitz, L. E., Suling, W. J. & Reynolds, R. C. (2002). J. Med. Chem. 45, 5604-5606.]); Monge et al. (1993[Monge, A., Palop, J. A., Del Castillo, J. C., Caldero, J. M., Roca, J., Romero, G., Del Rio, J. & Lasheras, B. (1993). J. Med. Chem. 36, 2745-2750.]); Kim et al. (2004[Kim, Y. B., Kim, Y. H., Park, J. Y. & Kim, S. K. (2004). Bioorg. Med. Chem. Lett. 14, 541-544.]); Bailly et al. (1999[Bailly, C., Echepare, S., Gago, F. & Waring, M. (1999). Anti-Cancer Drug Des. 14, 291-303.]). For a related structure, see: Caleb et al. (2009[Caleb, A. A., Bouhfid, R., Essassi, E. M. & El Ammari, L. (2009). Acta Cryst. E65, o2024-o2025.]).

[Scheme 1]

Experimental

Crystal data
  • C19H17N3O3

  • Mr = 335.36

  • Monoclinic, C c

  • a = 9.6314 (5) Å

  • b = 16.6596 (9) Å

  • c = 10.0749 (5) Å

  • β = 98.097 (3)°

  • V = 1600.46 (14) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 296 K

  • 0.43 × 0.31 × 0.19 mm

Data collection
  • Bruker X8 APEXII area-detector diffractometer

  • 23600 measured reflections

  • 2249 independent reflections

  • 1897 reflections with I > 2σ(I)

  • Rint = 0.078

Refinement
  • R[F2 > 2σ(F2)] = 0.038

  • wR(F2) = 0.097

  • S = 1.03

  • 2249 reflections

  • 226 parameters

  • 2 restraints

  • H-atom parameters constrained

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C11—H11⋯O1 0.93 2.33 2.860 (3) 116
C17—H17B⋯O1 0.97 2.53 3.061 (2) 114
C2—H2⋯O1i 0.93 2.42 3.283 (3) 154
C5—H5⋯O3ii 0.93 2.50 3.244 (3) 137
C18—H18B⋯O1i 0.97 2.44 3.367 (3) 159
Symmetry codes: (i) [x-{\script{1\over 2}}, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]; (ii) [x, -y+2, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. 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: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

Among the various classes of nitrogen containing heterocyclic compounds, quinoxaline derivatives display a broad spectrum of biological activities (Seitz et al., 2002; Monge et al., 1993; Kim et al., 2004). Quinoxalines play an important role as a basic skeleton for the design of a number of antibiotics such as echinomycin, actinomycin and leromycin. It has been reported that these compounds inhibit the growth of gram-positive bacteria and are also active against various transplantable tumors (Bailly et al., 1999). As a continuation of our research work devoted to the development of substituted dihydroquinoxalin-1-yl derivatives (Caleb et al., 2009) we report in this paper the synthesis and the crystal structure of the title compound.

The two fused six-membered rings (N1/N2/C1–C8) building the molecule of the title compound are approximately planar, the largest deviation from the mean plane being -0.055 (2) Å at C6 (Fig. 1). However, the plane through the two fused rings is slightly folded around the C1–C6 direction as indicated by the dihedral angle between them of 4.75 (8)°. The fused-ring system is linked to the phenyl ring (C10–C15) and to make a dihedral angle of 30.77 (9)°. The oxazolidin cycle (O2/N3/C18/C19/C20) is connected to the fused rings through the C16–C17 chain and build with them a dihedral angle of 68.42 (10)°. The molecular conformation is tabilized by intramolecular C—H···O hydrogen bonds (Table 1).

In the crystal, each molecule is linked to its symmetry equivalent partner by C2–H2···O1, C5–H5···O3 and C18–H18B···O1 non classic hydrogen bonds, forming a three dimensional network as shown in Fig. 2 and Table 2.

Related literature top

For biochemical properties of quinoxaline derivatives, see: Seitz et al. (2002); Monge et al. (1993); Kim et al. (2004); Bailly et al. (1999). For a related structure, see: Caleb et al. (2009).

Experimental top

In a 100 ml flask 3-phenyl-quinoxalin-2-one (1.25 mmol, 0.28 g) was reacted with dichloroethylamine hydrochloride (2.66 mmol, 0.50 g) in 40 ml of DMF in presence of K2CO3 (4 mmol, 0.52 g) and tetra-n-butylammonium bromide (0.01 mmol, 0.0032 g). The mixture was brought to reflux in a sand bath with magnetic stirring. The reaction progress was monitored by thin layer chromatography. After evaporation of the solvent under reduced pressure, the residue obtained was chromatographed on silica column (hexane/ethyl acetate 4:6 v/v). Recrystallization occurred in the same eluent.

Refinement top

H atoms were located in a difference map and treated as riding with C—H = 0.93–0.97 Å, and with Uiso(H) = 1.2 Ueq (C). In the absence of significant anomalous scattering, the absolute configuration could not be reliably determined and thus 2216 Friedel pairs were merged and any references to the Flack parameter were removed.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are represented as small circles or arbitrary radius.
[Figure 2] Fig. 2. Partial crystal packing of the title compound showing the hydrogen-bonding network (dashed lines).
3-[2-(3-Phenyl-2-oxo-1,2-dihydroquinoxalin-1-yl)ethyl]-1,3-oxazolidin-2-one top
Crystal data top
C19H17N3O3F(000) = 704
Mr = 335.36Dx = 1.392 Mg m3
Monoclinic, CcMo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2ycCell parameters from 2249 reflections
a = 9.6314 (5) Åθ = 2.5–29.6°
b = 16.6596 (9) ŵ = 0.10 mm1
c = 10.0749 (5) ÅT = 296 K
β = 98.097 (3)°Block, colourless
V = 1600.46 (14) Å30.43 × 0.31 × 0.19 mm
Z = 4
Data collection top
Bruker X8 APEXII area-detector
diffractometer
1897 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.078
Graphite monochromatorθmax = 29.6°, θmin = 2.5°
ϕ and ω scansh = 1313
23600 measured reflectionsk = 2323
2249 independent reflectionsl = 1313
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) = 0.097H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0647P)2]
where P = (Fo2 + 2Fc2)/3
2249 reflections(Δ/σ)max < 0.001
226 parametersΔρmax = 0.21 e Å3
2 restraintsΔρmin = 0.23 e Å3
Crystal data top
C19H17N3O3V = 1600.46 (14) Å3
Mr = 335.36Z = 4
Monoclinic, CcMo Kα radiation
a = 9.6314 (5) ŵ = 0.10 mm1
b = 16.6596 (9) ÅT = 296 K
c = 10.0749 (5) Å0.43 × 0.31 × 0.19 mm
β = 98.097 (3)°
Data collection top
Bruker X8 APEXII area-detector
diffractometer
1897 reflections with I > 2σ(I)
23600 measured reflectionsRint = 0.078
2249 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0382 restraints
wR(F2) = 0.097H-atom parameters constrained
S = 1.03Δρmax = 0.21 e Å3
2249 reflectionsΔρmin = 0.23 e Å3
226 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
C190.0392 (3)0.7294 (2)0.3896 (3)0.0830 (8)
H19A0.00570.76890.32700.100*
H19B0.02820.68760.40100.100*
C10.43510 (17)0.88352 (11)0.25887 (17)0.0419 (4)
C20.3351 (2)0.86112 (14)0.1505 (2)0.0560 (5)
H20.31440.80720.13370.067*
C30.2676 (2)0.91989 (16)0.0689 (2)0.0646 (6)
H30.20290.90480.00430.078*
C40.2938 (2)1.00054 (15)0.0931 (2)0.0605 (5)
H40.24731.03910.03660.073*
C50.3888 (2)1.02337 (13)0.2009 (2)0.0509 (4)
H50.40491.07760.21870.061*
C60.46138 (17)0.96571 (11)0.28424 (17)0.0412 (4)
C70.63967 (16)0.94028 (10)0.45793 (17)0.0391 (3)
C80.62007 (19)0.85246 (11)0.44060 (18)0.0431 (4)
O10.69145 (17)0.80218 (9)0.50945 (16)0.0599 (4)
C100.75182 (18)0.97196 (11)0.56143 (17)0.0419 (4)
C110.8763 (2)0.93092 (13)0.6025 (2)0.0548 (5)
H110.89100.88050.56720.066*
C120.9784 (2)0.96538 (16)0.6962 (2)0.0686 (7)
H121.06180.93800.72320.082*
C130.9575 (3)1.03972 (18)0.7496 (2)0.0726 (7)
H131.02611.06200.81310.087*
C140.8350 (3)1.08113 (15)0.7089 (2)0.0611 (5)
H140.82111.13150.74460.073*
C150.73293 (19)1.04777 (12)0.61482 (18)0.0469 (4)
H150.65091.07610.58690.056*
C160.4966 (2)0.74090 (11)0.3260 (2)0.0530 (5)
H16A0.58780.71600.32770.064*
H16B0.44220.72980.23940.064*
C170.4230 (2)0.70405 (11)0.4355 (2)0.0521 (4)
H17A0.42520.64610.42740.063*
H17B0.47440.71830.52210.063*
C180.1649 (2)0.69463 (14)0.3391 (2)0.0576 (5)
H18A0.16550.63650.34490.069*
H18B0.16940.71060.24720.069*
C200.2316 (2)0.76446 (12)0.5358 (2)0.0545 (5)
N10.51490 (16)0.82872 (9)0.34210 (15)0.0436 (3)
N20.56282 (15)0.99212 (10)0.38580 (14)0.0416 (3)
N30.27874 (17)0.72966 (9)0.43071 (16)0.0467 (4)
O20.08945 (18)0.76632 (12)0.51602 (18)0.0767 (5)
O30.2986 (2)0.79160 (12)0.63608 (19)0.0801 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C190.0653 (14)0.110 (2)0.0686 (17)0.0044 (14)0.0094 (12)0.0121 (15)
C10.0443 (8)0.0411 (8)0.0417 (9)0.0065 (7)0.0114 (7)0.0006 (7)
C20.0574 (11)0.0558 (12)0.0537 (11)0.0183 (9)0.0032 (9)0.0057 (9)
C30.0538 (10)0.0796 (16)0.0563 (12)0.0125 (11)0.0068 (9)0.0055 (11)
C40.0517 (10)0.0687 (14)0.0571 (12)0.0037 (9)0.0063 (8)0.0067 (11)
C50.0475 (9)0.0475 (10)0.0559 (11)0.0025 (8)0.0012 (8)0.0029 (9)
C60.0410 (7)0.0402 (9)0.0424 (9)0.0022 (6)0.0061 (6)0.0014 (7)
C70.0432 (8)0.0357 (8)0.0392 (8)0.0023 (7)0.0090 (6)0.0009 (7)
C80.0517 (9)0.0353 (8)0.0435 (9)0.0028 (7)0.0115 (7)0.0030 (7)
O10.0708 (9)0.0422 (7)0.0644 (9)0.0024 (7)0.0011 (7)0.0122 (7)
C100.0474 (8)0.0434 (9)0.0347 (8)0.0063 (7)0.0053 (7)0.0057 (7)
C110.0480 (10)0.0546 (11)0.0607 (12)0.0009 (8)0.0040 (8)0.0120 (9)
C120.0506 (11)0.0777 (17)0.0732 (16)0.0109 (10)0.0061 (10)0.0246 (13)
C130.0643 (13)0.0936 (19)0.0548 (13)0.0329 (13)0.0094 (10)0.0110 (12)
C140.0737 (13)0.0649 (13)0.0451 (10)0.0223 (11)0.0098 (9)0.0058 (10)
C150.0530 (9)0.0487 (10)0.0398 (9)0.0074 (8)0.0095 (7)0.0011 (8)
C160.0737 (13)0.0320 (8)0.0562 (11)0.0098 (9)0.0200 (9)0.0034 (8)
C170.0621 (11)0.0377 (9)0.0573 (11)0.0061 (8)0.0112 (9)0.0066 (8)
C180.0683 (12)0.0614 (12)0.0415 (10)0.0206 (10)0.0018 (9)0.0036 (9)
C200.0671 (12)0.0394 (9)0.0548 (12)0.0007 (8)0.0007 (9)0.0078 (9)
N10.0541 (8)0.0325 (7)0.0453 (8)0.0067 (6)0.0114 (6)0.0006 (6)
N20.0444 (7)0.0377 (7)0.0420 (7)0.0011 (5)0.0038 (5)0.0014 (6)
N30.0574 (8)0.0395 (7)0.0420 (8)0.0105 (6)0.0025 (6)0.0014 (6)
O20.0658 (9)0.0893 (13)0.0732 (12)0.0139 (9)0.0032 (8)0.0222 (10)
O30.0960 (13)0.0695 (11)0.0691 (11)0.0031 (9)0.0086 (9)0.0321 (9)
Geometric parameters (Å, º) top
C19—O21.436 (3)C11—C121.388 (3)
C19—C181.494 (4)C11—H110.9300
C19—H19A0.9700C12—C131.376 (4)
C19—H19B0.9700C12—H120.9300
C1—N11.395 (2)C13—C141.378 (4)
C1—C21.401 (2)C13—H130.9300
C1—C61.409 (2)C14—C151.382 (3)
C2—C31.381 (3)C14—H140.9300
C2—H20.9300C15—H150.9300
C3—C41.383 (4)C16—N11.480 (2)
C3—H30.9300C16—C171.521 (3)
C4—C51.371 (3)C16—H16A0.9700
C4—H40.9300C16—H16B0.9700
C5—C61.397 (3)C17—N31.448 (3)
C5—H50.9300C17—H17A0.9700
C6—N21.383 (2)C17—H17B0.9700
C7—N21.292 (2)C18—N31.452 (2)
C7—C81.482 (2)C18—H18A0.9700
C7—C101.488 (2)C18—H18B0.9700
C8—O11.233 (2)C20—O31.207 (3)
C8—N11.373 (2)C20—N31.341 (3)
C10—C111.391 (3)C20—O21.356 (3)
C10—C151.395 (3)
O2—C19—C18106.27 (19)C12—C13—C14120.0 (2)
O2—C19—H19A110.5C12—C13—H13120.0
C18—C19—H19A110.5C14—C13—H13120.0
O2—C19—H19B110.5C13—C14—C15119.9 (2)
C18—C19—H19B110.5C13—C14—H14120.0
H19A—C19—H19B108.7C15—C14—H14120.0
N1—C1—C2123.65 (16)C14—C15—C10120.6 (2)
N1—C1—C6117.21 (14)C14—C15—H15119.7
C2—C1—C6119.10 (17)C10—C15—H15119.7
C3—C2—C1119.32 (19)N1—C16—C17112.34 (17)
C3—C2—H2120.3N1—C16—H16A109.1
C1—C2—H2120.3C17—C16—H16A109.1
C2—C3—C4121.64 (19)N1—C16—H16B109.1
C2—C3—H3119.2C17—C16—H16B109.1
C4—C3—H3119.2H16A—C16—H16B107.9
C5—C4—C3119.6 (2)N3—C17—C16113.57 (17)
C5—C4—H4120.2N3—C17—H17A108.9
C3—C4—H4120.2C16—C17—H17A108.9
C4—C5—C6120.45 (19)N3—C17—H17B108.9
C4—C5—H5119.8C16—C17—H17B108.9
C6—C5—H5119.8H17A—C17—H17B107.7
N2—C6—C5117.88 (16)N3—C18—C19101.73 (18)
N2—C6—C1122.23 (16)N3—C18—H18A111.4
C5—C6—C1119.82 (16)C19—C18—H18A111.4
N2—C7—C8122.68 (15)N3—C18—H18B111.4
N2—C7—C10117.29 (15)C19—C18—H18B111.4
C8—C7—C10120.03 (15)H18A—C18—H18B109.3
O1—C8—N1120.46 (16)O3—C20—N3128.4 (2)
O1—C8—C7123.54 (17)O3—C20—O2121.6 (2)
N1—C8—C7116.00 (15)N3—C20—O2109.92 (17)
C11—C10—C15118.96 (17)C8—N1—C1122.27 (13)
C11—C10—C7122.94 (17)C8—N1—C16115.38 (15)
C15—C10—C7118.04 (16)C1—N1—C16122.29 (15)
C12—C11—C10119.8 (2)C7—N2—C6119.49 (14)
C12—C11—H11120.1C20—N3—C17122.08 (16)
C10—C11—H11120.1C20—N3—C18111.48 (17)
C13—C12—C11120.6 (2)C17—N3—C18122.53 (17)
C13—C12—H12119.7C20—O2—C19109.14 (19)
C11—C12—H12119.7
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···O10.932.332.860 (3)116
C17—H17B···O10.972.533.061 (2)114
C2—H2···O1i0.932.423.283 (3)154
C5—H5···O3ii0.932.503.244 (3)137
C18—H18B···O1i0.972.443.367 (3)159
Symmetry codes: (i) x1/2, y+3/2, z1/2; (ii) x, y+2, z1/2.

Experimental details

Crystal data
Chemical formulaC19H17N3O3
Mr335.36
Crystal system, space groupMonoclinic, Cc
Temperature (K)296
a, b, c (Å)9.6314 (5), 16.6596 (9), 10.0749 (5)
β (°) 98.097 (3)
V3)1600.46 (14)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.43 × 0.31 × 0.19
Data collection
DiffractometerBruker X8 APEXII area-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
23600, 2249, 1897
Rint0.078
(sin θ/λ)max1)0.694
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.097, 1.03
No. of reflections2249
No. of parameters226
No. of restraints2
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.21, 0.23

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···O10.932.332.860 (3)115.9
C17—H17B···O10.972.533.061 (2)114.2
C2—H2···O1i0.932.423.283 (3)153.7
C5—H5···O3ii0.932.503.244 (3)137.2
C18—H18B···O1i0.972.443.367 (3)158.9
Symmetry codes: (i) x1/2, y+3/2, z1/2; (ii) x, y+2, z1/2.
 

Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.

References

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