Issue contents
Download PDF of article
Download CIF
3D view
Navigation
Highlighting
Dictionary of Crystallography reference
IUPAC Gold Book reference
more ...
Download citation
FormatBIBTeX
EndNote
RefMan
Refer
Medline
CIF
SGML
Plain Text
share
Previous article
Next article
Previous article
Issue contents
Download PDF of article
Download CIF
3D view
Navigation
Highlighting
Dictionary of Crystallography reference
IUPAC Gold Book reference
more ...
Download citation
FormatBIBTeX
EndNote
RefMan
Refer
Medline
CIF
SGML
Plain Text
share
Next article

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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 8| August 2011| Page o1986
doi:10.1107/S1600536811026869

1,3-Di­allyl-6-bromo-1H-imidazo[4,5-b]pyridin-2(3H)-one

Siham Dahmani,a* Youssef Kandri Rodi,a Santiago V. Luis,b Michael Boltec and Lahcen El Ammarid

aLaboratoire de Chimie Organique Appliquée, Université Sidi Mohamed, Ben Abdallah, Faculté des Sciences et Techniques, Route d'Immouzzer, BP 2202 Fès, Morocco, bDepartamento de Quimica Inorganica & Organica, ESTCE, Universitat Jaume I, E-12080 Castellon, Spain, cInstitut für Anorganische Chemie, J. W. Goethe-Universität Frankfurt, Max-von-Laue-Strasse 7, 60438 Frankfurt/Main, Germany, and dLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Battouta, BP 1014, Rabat, Morocco
*Correspondence e-mail: s_dahmani12@yahoo.fr

(Received 28 June 2011; accepted 5 July 2011; online 9 July 2011)

In the mol­ecule of the title compound, C12H12BrN3O, the fused-ring system is essentially planar, the largest deviation from the mean plane being 0.0148 (3) Å. The two allyl groups are nearly perpendicular to the imidazo[4,5-b]pyridine plane [C—C—N—C torsion angles of 81.6 (4) and −77.2 (4)°] and point in the same direction. The planes through the atoms forming each allyl group are nearly perpendicular to the imidazo[4,5-b]pyridin-2-one system, as indicated by the dihedral angles between them of 80.8 (5) and 73.6 (5)°.

Related literature

For background to the biological activity of substituted imidazopyridines and related compounds, see: Barraclough et al. (1990[Barraclough, P., Beams, R. M., Black, J. W., Cambridge, D., Collard, D., Damaine, D. A., Firmin, D., Gerskowitch, V. P., Glen, R. C., Giles, H., Hill, A. P., Hull, R. A. D., Iyer, R., King, W. R., Livingstone, D. J., Nobbs, M. S., Randall, P., Shah, G. P., Smith, S., Vine, S. J. & Whiting, M. V. (1990). Eur. J. Med. Chem. 25, 467-477.]); Bavetsias et al. (2007[Bavetsias, V., Sun, C., Bouloc, N., Reynisson, J., Workman, P., Linardopoulos, S. & McDonald, E. (2007). Bioorg. Med. Chem. 17, 6567-6571.], 2010[Bavetsias, V., Large, J. M., Sun, C., Bouloc, N., Kosmopoulou, M., Matteucci, M., Wilsher, N. E., Martins, V., Reynisson, J., Atrash, B., Faisal, A., Urban, F., Valenti, M. & Brandon, A. H. (2010). J. Med. Chem. 53, 5213-5228.]); Coates et al. (1993[Coates, W. J., Connolly, B., Dhanak, D., Flynn, S. T. & Worby, A. (1993). J. Med. Chem. 36, 1387-1392.]); Liu et al. (2008[Liu, L., Xu, P., Zhou, L. & Lei, P. S. (2008). Chin. Chem. Lett. 19, 1-4.]); Ryabukhin et al. (2006[Ryabukhin, S. V., Plaskon, A. S., Volochnyuk, D. M. & Tolmachev, A. A. (2006). Synthesis, 21, 3715-3726.]); Schiffmann et al. (2006[Schiffmann, R., Neugebauer, A. & Klein, C. D. (2006). J. Med. Chem. 49, 511-522.]).

[Scheme 1]

Experimental

Crystal data

  • C12H12BrN3O

  • Mr = 294.16

  • Orthorhombic, P n a 21

  • a = 5.4110 (3) Å

  • b = 25.4205 (12) Å

  • c = 9.3170 (4) Å

  • V = 1281.56 (11) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 3.20 mm−1

  • T = 273 K

  • 0.52 × 0.32 × 0.14 mm
Data collection

  • Bruker CCD three-circle diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 1997[Bruker (1997). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.202, Tmax = 0.800

  • 8789 measured reflections

  • 3201 independent reflections

  • 2361 reflections with I > 2σ(I)

  • Rint = 0.027
Refinement

  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.100

  • S = 1.03

  • 3201 reflections

  • 156 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.44 e Å−3

  • Δρmin = −0.23 e Å−3

  • Absolute structure: Flack (1983)[Flack, H. D. (1983). Acta Cryst. A39, 876-881.], 1494 Friedel pairs

  • Flack parameter: 0.040 (17)

Data collection: SMART (Bruker, 1997[Bruker (1997). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1997[Bruker (1997). SMART, 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, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811026869/om2445sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811026869/om2445Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811026869/om2445Isup3.cml

checkCIF report


Comment top

Substituted imidazopyridines and structurally related compounds are of pharmacological and therapeutical interest. They have been tested for their potential as anticancer, inotropic (Barraclough et al., 1990), selective antihistamine (H1) agents and antibacterial activity (Liu et al., 2008). Imidazo[4,5-b]pyridine derivatives were also reported as Aurora kinases (Bavetsias et al., 2007); Bavetsias et al., 2010), and cyclic PDE inhibitors (Coates et al., 1993). The preparation of these compounds is usually straightforward, and a number of synthetic methods are already available (Ryabukhin et al., 2006; Schiffmann et al., 2006).

In this work, we report the synthesis of 1,3-diallyl-6-bromo-1,3-dihydroimidazo [4,5-b]pyridin-2-one via the reaction between 6-bromo-1,3-dihydro-imidazo [4,5 - b-]pyridin-2-one and allylbromide in DMF using K2CO3 as base (scheme1).

The Plot of the title compound molecule is shown in Fig.1. The two fused five and six-membered rings are nearly planar with the maximum deviation of -0.014 (3)Å from N1. The two allyl chains (–C7–C8–C9) and (–C10–C11–C12) are almost perpendicular to the imidazo[4,5-b]pyridine system mean plane as indicated by the following torsion angles C8–C7–N2–C5 and C11–C10–N3–C4 of 81.6 (4)° and -77.2 (4) ° respectively.

Related literature top

For background to the biological activity of substituted imidazopyridines and related compounds, see: Barraclough et al. (1990); Bavetsias et al. (2007, 2010); Coates et al. (1993); Liu et al. (2008); Ryabukhin et al. (2006); Schiffmann et al. (2006).

Experimental top

To a stirred solution of 6-bromo-1,3-dihydro-imidazo[4,5 - b-]pyridin-2- one (0.5 g; 2.33 mmol), K2CO3 (1.29 g; 9.34 mmol), and tetrabutylammonium bromide (0.07 g; 2.37 10 -4 mol) in DMF, allylbromide (0.5 ml; 5.84 mmol) was added dropwise. Stirring was continued at room temperature for 24 h. After completion of reaction (monitored by TLC), the salt was filtered and the solvent was removed under reduced pressure. The resulting residue was purified by column chromatography on silica gel using ethylacetate/hexane (1/1) as eluent. The crystals of the title compound are obtained by dissolving 80 mg of product in 4 ml of ethanol at about 353 K, followed by a slow evaporation of the solvent.

Refinement top

The origin of the non centro symmetric space group is fxed by the SHELXL program and the 1495 Friedel opposite refletions are not merged. H atoms were located in a difference map and treated as riding with C—H = 0.93 Å and 0.97 Å for aromatic and methylene respectively. All H atoms with Uiso(H) = 1.2 Ueq (aromatic and methylene).

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); 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, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. : Plot of the molecule of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small circles.
1,3-Diallyl-6-bromo-1H-imidazo[4,5-b]pyridin-2(3H)-one top
Crystal data top
C12H12BrN3OF(000) = 592
Mr = 294.16Dx = 1.525 Mg m−3
Orthorhombic, Pna21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: p 2c -2nCell parameters from 3201 reflections
a = 5.4110 (3) Åθ = 1.6–28.5°
b = 25.4205 (12) ŵ = 3.20 mm−1
c = 9.3170 (4) ÅT = 273 K
V = 1281.56 (11) Å3Block, colourless
Z = 40.52 × 0.32 × 0.14 mm
Data collection top
Bruker CCD three-circle
diffractometer		3201 independent reflections
Radiation source: sealed tube2361 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.027
phi and ω scansθmax = 28.5°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Bruker, 1997)		h = −6→7
Tmin = 0.202, Tmax = 0.800k = −25→34
8789 measured reflectionsl = −12→12
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)] = 0.036H-atom parameters constrained
wR(F2) = 0.100 w = 1/[σ2(Fo2) + (0.0402P)2 + 0.2176P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max < 0.001
3201 reflectionsΔρmax = 0.44 e Å−3
156 parametersΔρmin = −0.23 e Å−3
1 restraintAbsolute structure: Flack (1983), 1494 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.040 (17)
Crystal data top
C12H12BrN3OV = 1281.56 (11) Å3
Mr = 294.16Z = 4
Orthorhombic, Pna21Mo Kα radiation
a = 5.4110 (3) ŵ = 3.20 mm−1
b = 25.4205 (12) ÅT = 273 K
c = 9.3170 (4) Å0.52 × 0.32 × 0.14 mm
Data collection top
Bruker CCD three-circle
diffractometer		3201 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 1997)		2361 reflections with I > 2σ(I)
Tmin = 0.202, Tmax = 0.800Rint = 0.027
8789 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.036H-atom parameters constrained
wR(F2) = 0.100Δρmax = 0.44 e Å−3
S = 1.03Δρmin = −0.23 e Å−3
3201 reflectionsAbsolute structure: Flack (1983), 1494 Friedel pairs
156 parametersAbsolute structure parameter: 0.040 (17)
1 restraint
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 Rw factor 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
Br10.99838 (6)0.148410 (15)0.99886 (11)0.07396 (14)
N10.5607 (5)0.19539 (10)0.6617 (3)0.0585 (6)
N20.2257 (4)0.14754 (9)0.5520 (3)0.0541 (6)
N30.2480 (5)0.07428 (9)0.6813 (3)0.0552 (6)
O1−0.0599 (4)0.08103 (10)0.5080 (4)0.0730 (6)
C10.7552 (5)0.14820 (11)0.8523 (3)0.0515 (7)
C20.7283 (6)0.19139 (12)0.7678 (4)0.0592 (8)
H20.83210.21990.78420.071*
C30.6043 (6)0.10361 (12)0.8374 (3)0.0532 (7)
H30.62090.07390.89480.064*
C40.4298 (5)0.10753 (12)0.7306 (3)0.0496 (6)
C50.4169 (6)0.15329 (11)0.6493 (4)0.0489 (6)
C60.1188 (6)0.09843 (13)0.5717 (4)0.0579 (7)
C70.1361 (6)0.18683 (13)0.4530 (4)0.0621 (8)
H7A0.13490.22070.50110.075*
H7B−0.03310.17840.42740.075*
C80.2846 (7)0.19138 (15)0.3195 (4)0.0706 (9)
H80.23710.21730.25480.090 (12)*
C90.4653 (9)0.1641 (3)0.2855 (6)0.0939 (15)
H9A0.52010.13760.34660.113*
H9B0.54610.17010.19890.113*
C100.1712 (7)0.02523 (13)0.7497 (4)0.0694 (9)
H10A0.00910.01560.71370.083*
H10B0.15620.03110.85220.083*
C110.3410 (8)−0.01892 (15)0.7256 (5)0.0771 (10)
H110.3027−0.05030.77170.129 (19)*
C120.5362 (7)−0.01882 (17)0.6479 (6)0.0832 (12)
H12A0.58280.01160.59950.100*
H12B0.6313−0.04910.64000.100*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.05433 (18)0.1026 (3)0.0649 (2)0.00262 (14)−0.01189 (13)−0.0127 (2)
N10.0564 (13)0.0460 (14)0.0731 (17)−0.0070 (11)−0.0083 (14)0.0032 (13)
N20.0478 (13)0.0545 (14)0.0599 (15)−0.0015 (10)−0.0090 (11)0.0029 (10)
N30.0493 (13)0.0476 (13)0.0686 (15)−0.0089 (10)−0.0042 (12)0.0025 (11)
O10.0564 (12)0.0847 (15)0.0781 (16)−0.0178 (10)−0.0148 (16)−0.0040 (16)
C10.0412 (14)0.0642 (18)0.0489 (15)0.0007 (13)−0.0024 (12)−0.0096 (13)
C20.0507 (16)0.0556 (17)0.071 (2)−0.0074 (13)−0.0041 (15)−0.0080 (15)
C30.0489 (15)0.0567 (17)0.0539 (16)0.0026 (13)0.0034 (14)0.0046 (13)
C40.0416 (14)0.0549 (17)0.0522 (16)−0.0013 (11)0.0038 (12)−0.0024 (13)
C50.0446 (14)0.0454 (16)0.0566 (17)0.0003 (11)−0.0005 (14)−0.0055 (13)
C60.0531 (17)0.0630 (18)0.0575 (17)−0.0051 (14)−0.0016 (15)−0.0051 (15)
C70.0550 (17)0.0651 (19)0.0662 (19)0.0019 (13)−0.0108 (15)0.0016 (15)
C80.077 (2)0.083 (2)0.0523 (17)−0.0094 (19)−0.0090 (18)0.0031 (17)
C90.092 (4)0.119 (4)0.071 (3)0.003 (2)0.017 (2)−0.005 (3)
C100.065 (2)0.062 (2)0.081 (2)−0.0164 (15)0.0003 (19)0.0097 (17)
C110.089 (3)0.056 (2)0.086 (3)−0.0155 (18)0.004 (2)0.0058 (18)
C120.086 (3)0.066 (3)0.098 (3)−0.0118 (17)0.008 (2)−0.014 (2)
Geometric parameters (Å, º) top
Br1—C11.896 (3)C4—C51.390 (4)
N1—C51.328 (4)C7—C81.485 (5)
N1—C21.345 (4)C7—H7A0.9700
N2—C51.383 (4)C7—H7B0.9700
N2—C61.388 (4)C8—C91.240 (6)
N2—C71.444 (4)C8—H80.9300
N3—C41.376 (4)C9—H9A0.9300
N3—C61.381 (4)C9—H9B0.9300
N3—C101.461 (4)C10—C111.467 (6)
O1—C61.218 (4)C10—H10A0.9700
C1—C21.359 (4)C10—H10B0.9700
C1—C31.404 (4)C11—C121.281 (6)
C2—H20.9300C11—H110.9300
C3—C41.375 (5)C12—H12A0.9300
C3—H30.9300C12—H12B0.9300
C5—N1—C2113.5 (3)N2—C7—C8114.0 (3)
C5—N2—C6108.7 (2)N2—C7—H7A108.7
C5—N2—C7126.6 (2)C8—C7—H7A108.7
C6—N2—C7124.5 (3)N2—C7—H7B108.7
C4—N3—C6109.6 (3)C8—C7—H7B108.7
C4—N3—C10125.6 (3)H7A—C7—H7B107.6
C6—N3—C10123.9 (3)C9—C8—C7126.6 (4)
C2—C1—C3122.2 (3)C9—C8—H8116.7
C2—C1—Br1119.3 (2)C7—C8—H8116.7
C3—C1—Br1118.5 (2)C8—C9—H9A120.0
N1—C2—C1124.0 (3)C8—C9—H9B120.0
N1—C2—H2118.0H9A—C9—H9B120.0
C1—C2—H2118.0N3—C10—C11114.1 (3)
C4—C3—C1114.4 (3)N3—C10—H10A108.7
C4—C3—H3122.8C11—C10—H10A108.7
C1—C3—H3122.8N3—C10—H10B108.7
C3—C4—N3133.4 (3)C11—C10—H10B108.7
C3—C4—C5119.3 (3)H10A—C10—H10B107.6
N3—C4—C5107.3 (3)C12—C11—C10127.0 (4)
N1—C5—N2125.5 (3)C12—C11—H11116.5
N1—C5—C4126.7 (3)C10—C11—H11116.5
N2—C5—C4107.8 (2)C11—C12—H12A120.0
O1—C6—N3126.9 (3)C11—C12—H12B120.0
O1—C6—N2126.4 (3)H12A—C12—H12B120.0
N3—C6—N2106.6 (3)
C5—N1—C2—C11.8 (5)N3—C4—C5—N1−179.7 (3)
C3—C1—C2—N1−1.2 (5)C3—C4—C5—N2−179.1 (3)
Br1—C1—C2—N1−179.5 (3)N3—C4—C5—N20.5 (3)
C2—C1—C3—C40.2 (4)C4—N3—C6—O1−176.8 (4)
Br1—C1—C3—C4178.6 (2)C10—N3—C6—O1−7.0 (5)
C1—C3—C4—N3−179.4 (3)C4—N3—C6—N20.7 (3)
C1—C3—C4—C50.0 (4)C10—N3—C6—N2170.5 (3)
C6—N3—C4—C3178.7 (3)C5—N2—C6—O1177.2 (4)
C10—N3—C4—C39.2 (6)C7—N2—C6—O11.4 (5)
C6—N3—C4—C5−0.7 (3)C5—N2—C6—N3−0.4 (3)
C10—N3—C4—C5−170.3 (3)C7—N2—C6—N3−176.1 (3)
C2—N1—C5—N2178.2 (3)C5—N2—C7—C881.6 (4)
C2—N1—C5—C4−1.6 (5)C6—N2—C7—C8−103.5 (3)
C6—N2—C5—N1−179.9 (3)N2—C7—C8—C92.7 (6)
C7—N2—C5—N1−4.3 (5)C4—N3—C10—C11−77.2 (4)
C6—N2—C5—C4−0.1 (3)C6—N3—C10—C11114.7 (4)
C7—N2—C5—C4175.5 (3)N3—C10—C11—C12−3.3 (6)
C3—C4—C5—N10.8 (5)

Experimental details

Crystal data
Chemical formulaC12H12BrN3O
Mr294.16
Crystal system, space groupOrthorhombic, Pna21
Temperature (K)273
a, b, c (Å)5.4110 (3), 25.4205 (12), 9.3170 (4)
V (Å3)1281.56 (11)
Z4
Radiation typeMo Kα
µ (mm−1)3.20
Crystal size (mm)0.52 × 0.32 × 0.14
Data collection
DiffractometerBruker CCD three-circle
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 1997)
Tmin, Tmax0.202, 0.800
No. of measured, independent and
observed [I > 2σ(I)] reflections		8789, 3201, 2361
Rint0.027
(sin θ/λ)max (Å−1)0.670
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.100, 1.03
No. of reflections3201
No. of parameters156
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.44, −0.23
Absolute structureFlack (1983), 1494 Friedel pairs
Absolute structure parameter0.040 (17)

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

 

References

First citationBarraclough, P., Beams, R. M., Black, J. W., Cambridge, D., Collard, D., Damaine, D. A., Firmin, D., Gerskowitch, V. P., Glen, R. C., Giles, H., Hill, A. P., Hull, R. A. D., Iyer, R., King, W. R., Livingstone, D. J., Nobbs, M. S., Randall, P., Shah, G. P., Smith, S., Vine, S. J. & Whiting, M. V. (1990). Eur. J. Med. Chem. 25, 467–477.  CrossRef CAS Web of Science Google Scholar
 First citationBavetsias, V., Large, J. M., Sun, C., Bouloc, N., Kosmopoulou, M., Matteucci, M., Wilsher, N. E., Martins, V., Reynisson, J., Atrash, B., Faisal, A., Urban, F., Valenti, M. & Brandon, A. H. (2010). J. Med. Chem. 53, 5213–5228.  Web of Science CrossRef CAS PubMed Google Scholar
 First citationBavetsias, V., Sun, C., Bouloc, N., Reynisson, J., Workman, P., Linardopoulos, S. & McDonald, E. (2007). Bioorg. Med. Chem. 17, 6567–6571.  Web of Science CrossRef CAS Google Scholar
 First citationBruker (1997). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationCoates, W. J., Connolly, B., Dhanak, D., Flynn, S. T. & Worby, A. (1993). J. Med. Chem. 36, 1387–1392.  CrossRef CAS PubMed Web of Science Google Scholar
 First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
 First citationFarrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.  CrossRef CAS IUCr Journals Google Scholar
 First citationFlack, H. D. (1983). Acta Cryst. A39, 876–881.  CrossRef CAS Web of Science IUCr Journals Google Scholar
 First citationLiu, L., Xu, P., Zhou, L. & Lei, P. S. (2008). Chin. Chem. Lett. 19, 1–4.  Web of Science CrossRef CAS Google Scholar
 First citationRyabukhin, S. V., Plaskon, A. S., Volochnyuk, D. M. & Tolmachev, A. A. (2006). Synthesis, 21, 3715–3726.  Google Scholar
 First citationSchiffmann, R., Neugebauer, A. & Klein, C. D. (2006). J. Med. Chem. 49, 511–522.  Web of Science CrossRef PubMed CAS Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 8| August 2011| Page o1986
doi:10.1107/S1600536811026869
Follow Acta Cryst. E
Sign up for e-alerts
E-alerts
Follow Acta Cryst. on Twitter
Twitter
Follow us on facebook
Facebook
Sign up for RSS feeds
RSS