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ISSN: 2056-9890

2-Chloro-N-ethyl-9-iso­propyl-9H-purin-6-amine

aDepartment of Chemistry, Faculty of Technology, Tomas Bata University in Zlin, Nám. T. G. Masaryka 275, Zlín, 762 72, Czech Republic, and bDepartment of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, Brno-Bohunice, 625 00, Czech Republic
*Correspondence e-mail: rvicha@ft.utb.cz

(Received 29 June 2012; accepted 15 August 2012; online 23 August 2012)

In the title compound, C10H14ClN5, the purine ring system is essentially planar, with an r.m.s. deviation from the least-squares plane defined by the nine constituent atoms of 0.0063 (11) Å. In the crystal, mol­ecules are linked by weak N—H⋯N and C—H⋯π inter­actions.

Related literature

For the synthesis, see: Fiorini & Abel (1998[Fiorini, M. T. & Abel, Ch. (1998). Tetrahedron Lett. 39, 1827-1830.]). For related structures, see: Kubicki & Codding (2001[Kubicki, M. & Codding, P. W. (2001). Acta Cryst. E57, o332-o334.]); Rouchal et al. (2009a[Rouchal, M., Nečas, M., Carvalho, F. P. de & Vícha, R. (2009a). Acta Cryst. E65, o298-o299.],b[Rouchal, M., Nečas, M. & Vícha, R. (2009b). Acta Cryst. E65, o1268.], 2010[Rouchal, M., Nečas, M. & Vícha, R. (2010). Acta Cryst. E66, o1016.]). For other related literature, see: Legraverend & Grierson (2006[Legraverend, M. & Grierson, D. S. (2006). Bioorg. Med. Chem. 14, 3987-4006.]).

[Scheme 1]

Experimental

Crystal data
  • C10H14ClN5

  • Mr = 239.71

  • Monoclinic, P 21 /n

  • a = 8.1385 (2) Å

  • b = 9.6245 (2) Å

  • c = 14.8388 (3) Å

  • β = 92.997 (2)°

  • V = 1160.72 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.31 mm−1

  • T = 120 K

  • 0.40 × 0.40 × 0.20 mm

Data collection
  • Oxford Diffraction Xcalibur diffractometer with a Sapphire2 (large Be window) detector

  • Absorption correction: multi-scan CrysAlis RED (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]) Tmin = 0.973, Tmax = 1.000

  • 13543 measured reflections

  • 2041 independent reflections

  • 1793 reflections with I > 2σ(I)

  • Rint = 0.015

Refinement
  • R[F2 > 2σ(F2)] = 0.025

  • wR(F2) = 0.069

  • S = 1.07

  • 2041 reflections

  • 152 parameters

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

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the center of gravity of the pyridine ring (C1/N1/C2–C4/ N2).

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H3⋯N4i 0.837 (16) 2.205 (17) 2.9979 (16) 158.2 (15)
C8—H8⋯Cg1ii 1.00 (1) 2.90 (1) 3.6403 (13) 131 (1)
Symmetry codes: (i) -x, -y+1, -z+1; (ii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: CrysAlis CCD (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]); data reduction: CrysAlis RED; 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 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

The wide range of biological activities of di-, tri-, or tetrasubstituted purines is closely associated with essentially unlimited number of substituents that can be combined in the C2, C6, C8 and N9 positions of the purine ring (Legraverend & Grierson, 2006). The title molecule has been prepared as a part of our ongoing study of novel 2,6,9-trisubstituted purine series (Rouchal et al., 2009a,b, 2010). To the best of our knowledge, the title compound has not been described in the literature so far.

In the title molecule (Fig. 1), the purine unit is essentially planar, with a r.m.s. deviation of 0.0063 (11) Å from the least-squares plane defined by the nine constituent atoms. Although all pyrimidine atoms lie essentially in plane, the ring is markedly deformed from regular hexagon geometry with N1–C2–N3 angle of 132.0 (11)°. In the crystal structure (Fig. 2), molecules are connected by weak intermolecular N—H···N and C—H···π interactions (Table 1).

Related literature top

For the synthesis, see: Fiorini & Abel (1998). For related structures, see: Kubicki & Codding (2001); Rouchal et al. (2009a,b, 2010). For other related literature, see: Legraverend & Grierson (2006).

Experimental top

The title compound was prepared according to slightly modified literature procedure (Fiorini & Abel, 1998). 2,6-Dichloro-9-isopropyl-9H-purine (100 mg, 0.43 mmol) and ethylamine hydrochloride (37 mg, 0.45 mmol) were dissolved in the mixture of DMF (3 cm3) and triethylamine (87 mg, 0.86 mmol). The resulting solution was stirred at 90 °C for 3 h. Subsequently, the mixture was diluted with water and extracted with ethyl acetate (6 × 10 cm3). Combined organic layers were washed twice with brine, dried over Na2SO4 and evaporated in vacuum. Crystallization of the crude product from diethyl ether at room temperature provided desired compound as colorless crystals (67 mg, 65%, mp 390–393 K) suitable for X-ray diffraction analysis.

Refinement top

All carbon bound H atoms were placed at calculated positions and were refined as riding with their Uiso set to either 1.2Ueq or 1.5Ueq (methyl) of the respective carrier atoms. The positions of methyl H atoms were optimized rotationally. Nitrogen bound H atom was located in a difference Fourier map and refined freely.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: CrysAlis RED (Oxford Diffraction, 2009); data reduction: CrysAlis RED (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
Fig. 1.The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are presented as small spheres of arbitrary radius.

Fig. 2. A view of the N—H···N (black dotted lines) and C—H···π (red dashed lines) interactions in the crystal structure of the title compound. H atoms non-participating in hydrogen-bonding were omitted for clarity. Symmetry codes: (i) -x, -y + 1, -z + 1; (ii) -x + 0.5, y - 0.5, -z + 0.5.
2-chloro-N-ethyl-9-isopropyl-9H-purine-6-amine top
Crystal data top
C10H14ClN5F(000) = 504
Mr = 239.71Dx = 1.372 Mg m3
Monoclinic, P21/nMelting point: 392 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 8.1385 (2) ÅCell parameters from 9070 reflections
b = 9.6245 (2) Åθ = 2.9–27.2°
c = 14.8388 (3) ŵ = 0.31 mm1
β = 92.997 (2)°T = 120 K
V = 1160.72 (4) Å3Block, colourless
Z = 40.40 × 0.40 × 0.20 mm
Data collection top
Oxford Diffraction Xcalibur
diffractometer with a Sapphire2 (large Be window) detector
2041 independent reflections
Radiation source: Enhance (Mo) X-ray Source1793 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.015
Detector resolution: 8.4353 pixels mm-1θmax = 25.0°, θmin = 2.9°
ω scanh = 99
Absorption correction: multi-scan
CrysAlis RED (Oxford Diffraction, 2009)
k = 1011
Tmin = 0.973, Tmax = 1.000l = 1717
13543 measured reflections
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.025 w = 1/[σ2(Fo2) + (0.0372P)2 + 0.3781P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.069(Δ/σ)max = 0.001
S = 1.07Δρmax = 0.21 e Å3
2041 reflectionsΔρmin = 0.22 e Å3
152 parameters
Crystal data top
C10H14ClN5V = 1160.72 (4) Å3
Mr = 239.71Z = 4
Monoclinic, P21/nMo Kα radiation
a = 8.1385 (2) ŵ = 0.31 mm1
b = 9.6245 (2) ÅT = 120 K
c = 14.8388 (3) Å0.40 × 0.40 × 0.20 mm
β = 92.997 (2)°
Data collection top
Oxford Diffraction Xcalibur
diffractometer with a Sapphire2 (large Be window) detector
2041 independent reflections
Absorption correction: multi-scan
CrysAlis RED (Oxford Diffraction, 2009)
1793 reflections with I > 2σ(I)
Tmin = 0.973, Tmax = 1.000Rint = 0.015
13543 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0250 restraints
wR(F2) = 0.069H atoms treated by a mixture of independent and constrained refinement
S = 1.07Δρmax = 0.21 e Å3
2041 reflectionsΔρmin = 0.22 e Å3
152 parameters
Special details top

Experimental. Spectral properties of title compound:1H NMR (CDCl3): 1.30 (t, J = 7.3 Hz, 3H, NHCH2CH3), 1.57 (d, J = 6.6 Hz, 6H, CH(CH3)2), 3.72 (m, 2H, NHCH2CH3), 4.80 (septet, J = 6.9 Hz, 1H, CH(CH3)2), 5.84 (bs, 1H, NHCH2CH3), 7.76 (s, 1H, NC8HN) p.p.m.. 13 C NMR (CDCl3): 15.1(CH3), 23.0(CH3), 36.0(CH2), 47.1(CH), 119.0(C), 137.6(CH), 154.5(C), 155.5(C) p.p.m.. IR (KBr): 3103(m), 2974(m), 2933(w), 1726(w), 1605(s), 1560(m), 1481(w), 1454(w), 1435(w), 1404(m), 1362(m), 1309(s), 1227(s), 1188(w), 130(w), 1034(s), 941(m), 874(m), 785(m), 657(m), 609(w) cm-1. GC—EI—MS (200 °C, 70 eV): 241(M+(37Cl), 30), 240 (13), 239(M+(35Cl), 95), 226 (20), 225 (7), 224 (62), 213 (10), 211 (32), 199 (9), 198 (18), 197 (27), 196 (45), 184 (32), 183 (9), 182 (100), 171 (17), 169 (54), 161 (27), 160 (17), 156 (6), 155 (10), 154 (19), 153 (8), 146 (20), 134 (43), 133 (22), 120 (6), 119 (47), 118 (5), 108 (9), 107 (12), 106 (7), 93 (8), 92 (21), 80 (7), 68 (5), 67 (9), 66 (11), 65 (6), 55 (6), 54 (12), 53 (9), 44 (74), 43 (34), 42 (11), 41 (34), 40 (6) m/z(%). Elemental analysis calc for C10H14ClN4 (239.70) C 50.11, H 5.89, N 29.22; found C 50.16, H 5.92, N 29.02.

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 > 2σ(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
Cl10.71286 (4)0.25662 (4)0.37828 (2)0.02326 (12)
N10.46503 (13)0.39081 (11)0.30528 (7)0.0176 (2)
N20.45822 (13)0.33371 (11)0.46370 (7)0.0172 (2)
N30.24124 (14)0.38987 (12)0.55160 (7)0.0195 (3)
H30.147 (2)0.4230 (17)0.5565 (11)0.027 (4)*
N40.08494 (13)0.52739 (11)0.38017 (7)0.0194 (3)
N50.21933 (13)0.51796 (11)0.25145 (7)0.0180 (2)
C10.52134 (15)0.33857 (13)0.38306 (8)0.0169 (3)
C20.31722 (15)0.45181 (13)0.31630 (8)0.0164 (3)
C30.23370 (15)0.45883 (13)0.39493 (9)0.0164 (3)
C40.30943 (15)0.39438 (13)0.47204 (8)0.0166 (3)
C50.31812 (16)0.31996 (15)0.63006 (8)0.0211 (3)
H5A0.27940.36350.68550.025*
H5B0.43880.33290.63010.025*
C60.27990 (19)0.16560 (16)0.63171 (10)0.0312 (4)
H6A0.33270.12380.68610.047*
H6B0.32180.12120.57810.047*
H6C0.16060.15210.63210.047*
C70.08323 (16)0.56029 (14)0.29428 (9)0.0199 (3)
H70.00510.60940.26440.024*
C80.25198 (17)0.53989 (14)0.15553 (9)0.0210 (3)
H80.15940.59620.12770.025*
C90.40995 (17)0.62252 (15)0.14745 (9)0.0250 (3)
H9A0.40350.70890.18200.038*
H9B0.42440.64450.08390.038*
H9C0.50370.56740.17120.038*
C100.25535 (19)0.40217 (16)0.10584 (10)0.0285 (3)
H10A0.15060.35370.11190.043*
H10B0.34550.34480.13170.043*
H10C0.27220.41900.04180.043*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.01873 (19)0.0305 (2)0.02086 (19)0.00947 (13)0.00355 (13)0.00232 (13)
N10.0166 (6)0.0174 (6)0.0189 (6)0.0010 (4)0.0019 (4)0.0002 (4)
N20.0164 (5)0.0172 (6)0.0181 (5)0.0006 (4)0.0015 (4)0.0013 (4)
N30.0169 (6)0.0237 (6)0.0181 (6)0.0048 (5)0.0037 (4)0.0010 (4)
N40.0170 (6)0.0193 (6)0.0220 (6)0.0021 (4)0.0018 (4)0.0002 (5)
N50.0164 (6)0.0199 (6)0.0179 (5)0.0021 (4)0.0012 (4)0.0019 (5)
C10.0148 (6)0.0156 (7)0.0203 (6)0.0007 (5)0.0019 (5)0.0015 (5)
C20.0158 (6)0.0141 (7)0.0191 (6)0.0012 (5)0.0004 (5)0.0003 (5)
C30.0151 (6)0.0143 (7)0.0200 (6)0.0007 (5)0.0014 (5)0.0015 (5)
C40.0169 (6)0.0136 (6)0.0192 (6)0.0023 (5)0.0010 (5)0.0027 (5)
C50.0202 (7)0.0265 (8)0.0166 (6)0.0029 (6)0.0020 (5)0.0003 (5)
C60.0311 (8)0.0295 (9)0.0329 (8)0.0026 (6)0.0016 (6)0.0085 (6)
C70.0159 (6)0.0200 (7)0.0238 (7)0.0025 (5)0.0014 (5)0.0015 (6)
C80.0202 (7)0.0261 (8)0.0169 (6)0.0038 (5)0.0008 (5)0.0044 (5)
C90.0255 (7)0.0241 (8)0.0258 (7)0.0015 (6)0.0046 (6)0.0065 (6)
C100.0300 (8)0.0333 (9)0.0220 (7)0.0012 (6)0.0001 (6)0.0046 (6)
Geometric parameters (Å, º) top
Cl1—C11.7516 (13)C5—H5A0.9900
N1—C11.3189 (16)C5—H5B0.9900
N1—C21.3561 (16)C6—H6A0.9800
N2—C11.3274 (16)C6—H6B0.9800
N2—C41.3558 (16)C6—H6C0.9800
N3—C41.3312 (17)C7—H70.9500
N3—C51.4572 (17)C8—C101.518 (2)
N3—H30.837 (17)C8—C91.5217 (19)
N4—C71.3126 (17)C8—H81.0000
N4—C31.3861 (17)C9—H9A0.9800
N5—C71.3677 (17)C9—H9B0.9800
N5—C21.3733 (16)C9—H9C0.9800
N5—C81.4766 (16)C10—H10A0.9800
C2—C31.3824 (18)C10—H10B0.9800
C3—C41.4143 (18)C10—H10C0.9800
C5—C61.518 (2)
C1—N1—C2109.23 (11)C5—C6—H6A109.5
C1—N2—C4117.17 (11)C5—C6—H6B109.5
C4—N3—C5122.83 (12)H6A—C6—H6B109.5
C4—N3—H3119.4 (11)C5—C6—H6C109.5
C5—N3—H3117.6 (11)H6A—C6—H6C109.5
C7—N4—C3103.48 (10)H6B—C6—H6C109.5
C7—N5—C2105.47 (10)N4—C7—N5114.31 (12)
C7—N5—C8126.60 (11)N4—C7—H7122.8
C2—N5—C8127.93 (11)N5—C7—H7122.8
N1—C1—N2132.00 (12)N5—C8—C10110.62 (11)
N1—C1—Cl1113.92 (9)N5—C8—C9110.24 (11)
N2—C1—Cl1114.06 (9)C10—C8—C9112.42 (12)
N1—C2—N5127.02 (11)N5—C8—H8107.8
N1—C2—C3126.96 (12)C10—C8—H8107.8
N5—C2—C3106.02 (11)C9—C8—H8107.8
C2—C3—N4110.72 (11)C8—C9—H9A109.5
C2—C3—C4116.66 (12)C8—C9—H9B109.5
N4—C3—C4132.59 (12)H9A—C9—H9B109.5
N3—C4—N2118.86 (12)C8—C9—H9C109.5
N3—C4—C3123.20 (12)H9A—C9—H9C109.5
N2—C4—C3117.94 (11)H9B—C9—H9C109.5
N3—C5—C6112.64 (11)C8—C10—H10A109.5
N3—C5—H5A109.1C8—C10—H10B109.5
C6—C5—H5A109.1H10A—C10—H10B109.5
N3—C5—H5B109.1C8—C10—H10C109.5
C6—C5—H5B109.1H10A—C10—H10C109.5
H5A—C5—H5B107.8H10B—C10—H10C109.5
C2—N1—C1—N22.0 (2)C5—N3—C4—N21.24 (19)
C2—N1—C1—Cl1179.87 (9)C5—N3—C4—C3178.29 (12)
C4—N2—C1—N11.4 (2)C1—N2—C4—N3179.07 (11)
C4—N2—C1—Cl1179.56 (9)C1—N2—C4—C30.48 (17)
C1—N1—C2—N5179.90 (12)C2—C3—C4—N3178.20 (12)
C1—N1—C2—C30.80 (18)N4—C3—C4—N30.3 (2)
C7—N5—C2—N1179.21 (12)C2—C3—C4—N21.33 (17)
C8—N5—C2—N10.8 (2)N4—C3—C4—N2179.24 (13)
C7—N5—C2—C30.21 (14)C4—N3—C5—C685.04 (16)
C8—N5—C2—C3179.74 (12)C3—N4—C7—N50.27 (15)
N1—C2—C3—N4179.04 (12)C2—N5—C7—N40.05 (15)
N5—C2—C3—N40.38 (14)C8—N5—C7—N4179.99 (12)
N1—C2—C3—C40.68 (19)C7—N5—C8—C10114.50 (14)
N5—C2—C3—C4178.74 (11)C2—N5—C8—C1065.56 (16)
C7—N4—C3—C20.40 (14)C7—N5—C8—C9120.53 (14)
C7—N4—C3—C4178.41 (14)C2—N5—C8—C959.40 (17)
Hydrogen-bond geometry (Å, º) top
Cg1 is the center of gravity of the pyridine ring (C1, N1, C2, C3, C4, N2).
D—H···AD—HH···AD···AD—H···A
N3—H3···N4i0.837 (16)2.205 (17)2.9979 (16)158.2 (15)
C8—H8···Cg1ii1.00 (1)2.90 (1)3.6403 (13)131 (1)
Symmetry codes: (i) x, y+1, z+1; (ii) x+1/2, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC10H14ClN5
Mr239.71
Crystal system, space groupMonoclinic, P21/n
Temperature (K)120
a, b, c (Å)8.1385 (2), 9.6245 (2), 14.8388 (3)
β (°) 92.997 (2)
V3)1160.72 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.31
Crystal size (mm)0.40 × 0.40 × 0.20
Data collection
DiffractometerOxford Diffraction Xcalibur
diffractometer with a Sapphire2 (large Be window) detector
Absorption correctionMulti-scan
CrysAlis RED (Oxford Diffraction, 2009)
Tmin, Tmax0.973, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
13543, 2041, 1793
Rint0.015
(sin θ/λ)max1)0.594
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.025, 0.069, 1.07
No. of reflections2041
No. of parameters152
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.21, 0.22

Computer programs: CrysAlis CCD (Oxford Diffraction, 2009), CrysAlis RED (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008).

Hydrogen-bond geometry (Å, º) top
Cg1 is the center of gravity of the pyridine ring (C1, N1, C2, C3, C4, N2).
D—H···AD—HH···AD···AD—H···A
N3—H3···N4i0.837 (16)2.205 (17)2.9979 (16)158.2 (15)
C8—H8···Cg1ii0.9997 (13)2.90380 (10)3.6403 (13)131.15 (8)
Symmetry codes: (i) x, y+1, z+1; (ii) x+1/2, y+1/2, z+1/2.
 

Acknowledgements

The financial support of this work by the Tomas Bata Foundation and by the Inter­nal Founding Agency of Tomas Bata University in Zlin (project No. IGA/FT/2012/016) is gratefully acknowledged.

References

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