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

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ISSN: 2056-9890

3β-Acet­­oxy-lup-20(29)-en-28-yl 1H-1,2,4-tri­azole-1-carboxyl­ate

aLaboratório de Química Farmacêutica, Faculdade de Farmácia, Universidade de Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, P-3000-548 Coimbra, Portugal, and bCEMDRX, Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, P-3004-516 Coimbra, Portugal
*Correspondence e-mail: jap@pollux.fis.uc.pt

(Received 21 October 2010; accepted 25 October 2010; online 31 October 2010)

The title triterpene, C35H53N3O4, is a C-28 carbamate derivative of 3β-acet­oxy­betulin prepared in a one-step reaction from the commercially available 1,1′-carbonyl-di(1,2,4-triazole) (CDT), crystallized from acetone/n-hexane. All rings are trans fused. The carbamate and acetate substituents are in axial and equatorial positions, respectively. A quantum chemical ab initio Roothaan Hartree–Fock calculation of the equilibrium geometry of the isolated mol­ecule gives values for bond lengths and valency angles in close agreement with experimental values. The calculation also reproduces the observed mol­ecular conformation, with puckering parameters that agree well with those determined from the crystallographic study.

Related literature

For the cytotoxic activity of penta­cyclic triterpenoids, see: Petronelli et al. (2009[Petronelli, A., Pannitteri, G. & Testa, U. (2009). Anticancer Drugs, 20, 880-892.]); Fulda (2009[Fulda, S. (2009). Mol. Nutr. Food Res. 53, 140-146.]); Salvador (2010[Salvador, J. A. R. (2010). Pentacyclic Triterpenes as Promising Agents in Cancer, edited by J. A. R. Salvador. Hauppauge, New York: Nova Science Publishers.]). For the biological activity of betulin and betulinic acid, see: Dzubak et al. (2006[Dzubak, P., Hajduch, M., Vydra, D., Hustova, A., Kvasnica, M., Biedermann, D., Markova, L., Urban, M. & Sarek, J. (2006). Nat. Prod. Rep. 23, 294-411.]); Tolstikova et al. (2006[Tolstikova, T. G., Sorokina, I. V., Tolstikov, G. A., Tolstikov, A. G. & Flekhter, O. B. (2006). Russ. J. Bioorg. Chem. 32, 37-49.]). For the synthesis of carbamate derivatives of betulin and betulinic acid, see: Santos et al. (2009[Santos, R. C., Salvador, J. A. R., Marín, S. & Cascante, M. (2009). Bioorg. Med. Chem. 17, 6241-6250.], 2010b[Santos, R. C., Salvador, J. A. R., Marín, S., Cascante, M., Moreira, J. N. & Dinis, T. C. P. (2010b). Bioorg. Med. Chem. 18, 4385-4396.]). For related structures, see Santos et al. (2010a[Santos, R. C., Matos Beja, A., Salvador, J. A. R. & Paixão, J. A. (2010a). Acta Cryst. E66, o1878-o1879.]). For puckering and asymmetry parameters, see Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]); Duax & Norton (1975[Duax, W. L. & Norton, D. A. (1975). Atlas of Steroid Structure. New York: Plenum Press.]). The quantum chemical calculations were performed with the computer program GAMESS (Schmidt et al., 1993[Schmidt, M. W., Baldrige, K. K., Boatz, J. A., Elbert, S. T., Gordon, M. S., Jensen, J. J., Koseki, S., Matsunaga, N., Nguyen, K. A., Sue, S., Windus, T. L., Dupuis, M. & Montgomery, J. A. (1993). J. Comput. Chem. 14, 1347-1363.]).

[Scheme 1]

Experimental

Crystal data
  • C35H53N3O4

  • Mr = 579.80

  • Orthorhombic, P 21 21 21

  • a = 9.2108 (4) Å

  • b = 15.5383 (6) Å

  • c = 22.9270 (9) Å

  • V = 3281.3 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 293 K

  • 0.28 × 0.24 × 0.23 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2000[Sheldrick, G. M. (2000). SADABS. University of Göttingen, Germany.]) Tmin = 0.880, Tmax = 1.00

  • 61378 measured reflections

  • 4625 independent reflections

  • 3264 reflections with I > 2σ(I)

  • Rint = 0.046

Refinement
  • R[F2 > 2σ(F2)] = 0.047

  • wR(F2) = 0.137

  • S = 1.02

  • 4625 reflections

  • 386 parameters

  • H-atom parameters constrained

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.26 e Å−3

Data collection: APEX2 (Bruker, 2006[Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2006[Bruker (2006). APEX2 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: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Pentacyclic triterpenoids are a class of pharmacologically active and structurally rich natural products with privileged motifs for further modifications and structure–activity relationship (SAR) analyses (Petronelli et al., 2009). Some natural triterpenoids such as betulin and betulinic acid have shown remarkable effects in suppressing tumorigenesis as well as in inhibiting tumor (Fulda, 2009). Recently, we focused our attention on the synthesis of lupane-type carbamates and N-acylheterocyclic bearing derivatives. Our results showed that addition of an heterocyclic moiety at the C-3 and/or C-28 positions of betulin and betulinic acid can result in more potent in vitro anticancer agents than betulinic acid, with IC50 values between 0.8 and 28.2 µM, in some human cancer cell lines of different tumor types (Santos et al., 2009, 2010b). The general procedure for the synthesis of the novel lupane derivatives involved dissolution of the corresponding lupanes and CDI, CBMI or CDT in THF at reflux, under N2 (Santos et al., 2009, 2010b). In this case the reaction of 3β-acetoxybetulin with CDT afforded the carbamate derivative 3β-acetoxy-lup-20 (29)-en-28-yl-1H-1,2,4-triazole-1-carboxylate in good yield (Santos et al., 2010b).

Mindful of the biological and synthetic importance of such molecules, we report in this communication the molecular structure of the 3β-acetoxy-lup-20 (29)-en-28-yl-1H-1,2,4-triazole-1-carboxylate determined by single-crystal X-ray diffraction, and compare it with that of the free molecule as given by quantum mechanical ab initio calculation. The structure of this compound with the corresponding atomic numbering scheme is shown in Fig. 1.

All six-membered rings are fused trans and have slightly distorted chair conformations; the 5-membered ring adopts a twisted conformation around C17—C18, as shown by the Cremer & Pople (1975) parameters: [ring A: Q = 0.565 (3) Å, θ = 3.4 (3)° and φ = 129 (5)°; B: Q = 0.569 (3) Å, θ = 8.9 (3)° and φ = 17.9 (18)°; C: Q = 0.605 (3) Å, θ = 7.9 (3)° and φ = 323.7 (19)°; D: Q = 0.558 (3) Å, θ = 173.7 (3)° and φ = 80 (3)°; E: q2 = 0.451 (3) Å, φ2 = 9.6 (4)°].

The carbamate and acetate substituints are in axial and equatorial positions, respectively.

In order to gain some insight on how the crystal packing of (I) might affect the molecular geometry we have performed a quantum chemical calculation on the equilibrium geometry of the free molecule. These ab initio calculations reproduce well the observed bond length and valency angles of the molecule with the exception of bonds C30—C20 [obs: 1.467 (5) calc: 1.511 Å] and N28—C28B [obs: 1.331 (6) calc: 1.366 Å] Also, the calculated conformation of the rings are very close to the experimental values. The conformation of the molecule mainly differs from a small rotation of the triazole-carboxylate substituent around the C28–O28A bond as shown by the values of the C28—O28A—C28A—O28B torsion angle [obs: 149.6 (3) calc: 179.4]

There are no strong hydrogen bonds in the crystal structure, due to the lack of strong H-donors.

Related literature top

For the cytotoxic activity of pentacyclic triterpenoids, see: Petronelli et al. (2009); Fulda (2009); Salvador (2010). For the biological activity of betulin and betulinic acid, see: Dzubak et al. (2006); Tolstikova et al. (2006). For the synthesis of carbamate derivatives of betulin and betulinic acid, see: Santos et al. (2009, 2010b). For related structures, see Santos et al. (2010a). For puckering and asymmetry parameters, see Cremer & Pople (1975); Duax & Norton (1975). The quantum chemical calculations were performed with the computer program GAMESS (Schmidt et al., 1993).

Experimental top

The synthesis of 3β-acetoxy-lup-20 (29)-en-28-yl-1H-1,2,4-triazole-1-carboxylate was efficiently accomplished by reaction with CDT (Santos et al., 2009). The product of this reaction was isolated in 74% yield and identified as the title compound from MS, IR, 1H and 13C NMR spectroscopy data (Santos et al., 2010b). Recrystallization from acetone/n-hexane at room temperature gave colourless single crystals suitable for X-ray diffraction analysis.

The ab initio calculations were performed with the computer program GAMESS (Schmidt et al., 1993). A molecular orbital Roothaan Hartree-Fock method was used with an extended 6-31 G(d,p) basis set. Tight conditions for convergence of both the self-consistent field cycles and maximum density and energy gradient variations were imposed (10-6 atomic units). The program was run on the Milipeia cluster of UC-LCA (using 16 Opteron cores, 2.2 GHz running Linux).

Refinement top

All H atoms were refined as riding on their parent atoms using SHELXL97 defaults. The absolute configuration was not determined from the X-ray data, as the molecule lacks any strong anomalous scatterer atom at the Mo Kα wavelength, but was known from the synthetic route. Friedel pairs of reflections (2247 pairs) were merged before refinement.

Structure description top

Pentacyclic triterpenoids are a class of pharmacologically active and structurally rich natural products with privileged motifs for further modifications and structure–activity relationship (SAR) analyses (Petronelli et al., 2009). Some natural triterpenoids such as betulin and betulinic acid have shown remarkable effects in suppressing tumorigenesis as well as in inhibiting tumor (Fulda, 2009). Recently, we focused our attention on the synthesis of lupane-type carbamates and N-acylheterocyclic bearing derivatives. Our results showed that addition of an heterocyclic moiety at the C-3 and/or C-28 positions of betulin and betulinic acid can result in more potent in vitro anticancer agents than betulinic acid, with IC50 values between 0.8 and 28.2 µM, in some human cancer cell lines of different tumor types (Santos et al., 2009, 2010b). The general procedure for the synthesis of the novel lupane derivatives involved dissolution of the corresponding lupanes and CDI, CBMI or CDT in THF at reflux, under N2 (Santos et al., 2009, 2010b). In this case the reaction of 3β-acetoxybetulin with CDT afforded the carbamate derivative 3β-acetoxy-lup-20 (29)-en-28-yl-1H-1,2,4-triazole-1-carboxylate in good yield (Santos et al., 2010b).

Mindful of the biological and synthetic importance of such molecules, we report in this communication the molecular structure of the 3β-acetoxy-lup-20 (29)-en-28-yl-1H-1,2,4-triazole-1-carboxylate determined by single-crystal X-ray diffraction, and compare it with that of the free molecule as given by quantum mechanical ab initio calculation. The structure of this compound with the corresponding atomic numbering scheme is shown in Fig. 1.

All six-membered rings are fused trans and have slightly distorted chair conformations; the 5-membered ring adopts a twisted conformation around C17—C18, as shown by the Cremer & Pople (1975) parameters: [ring A: Q = 0.565 (3) Å, θ = 3.4 (3)° and φ = 129 (5)°; B: Q = 0.569 (3) Å, θ = 8.9 (3)° and φ = 17.9 (18)°; C: Q = 0.605 (3) Å, θ = 7.9 (3)° and φ = 323.7 (19)°; D: Q = 0.558 (3) Å, θ = 173.7 (3)° and φ = 80 (3)°; E: q2 = 0.451 (3) Å, φ2 = 9.6 (4)°].

The carbamate and acetate substituints are in axial and equatorial positions, respectively.

In order to gain some insight on how the crystal packing of (I) might affect the molecular geometry we have performed a quantum chemical calculation on the equilibrium geometry of the free molecule. These ab initio calculations reproduce well the observed bond length and valency angles of the molecule with the exception of bonds C30—C20 [obs: 1.467 (5) calc: 1.511 Å] and N28—C28B [obs: 1.331 (6) calc: 1.366 Å] Also, the calculated conformation of the rings are very close to the experimental values. The conformation of the molecule mainly differs from a small rotation of the triazole-carboxylate substituent around the C28–O28A bond as shown by the values of the C28—O28A—C28A—O28B torsion angle [obs: 149.6 (3) calc: 179.4]

There are no strong hydrogen bonds in the crystal structure, due to the lack of strong H-donors.

For the cytotoxic activity of pentacyclic triterpenoids, see: Petronelli et al. (2009); Fulda (2009); Salvador (2010). For the biological activity of betulin and betulinic acid, see: Dzubak et al. (2006); Tolstikova et al. (2006). For the synthesis of carbamate derivatives of betulin and betulinic acid, see: Santos et al. (2009, 2010b). For related structures, see Santos et al. (2010a). For puckering and asymmetry parameters, see Cremer & Pople (1975); Duax & Norton (1975). The quantum chemical calculations were performed with the computer program GAMESS (Schmidt et al., 1993).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. ORTEPII plot of the title compound showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% level. H atoms are depicted as spheres of arbitrary radii.
3β-Acetoxy-lup-20 (29)-en-28-yl 1H-1,2,4-triazole-1-carboxylate top
Crystal data top
C35H53N3O4Dx = 1.174 Mg m3
Mr = 579.80Melting point: 386 K
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
a = 9.2108 (4) ÅCell parameters from 5792 reflections
b = 15.5383 (6) Åθ = 2.6–22.2°
c = 22.9270 (9) ŵ = 0.08 mm1
V = 3281.3 (2) Å3T = 293 K
Z = 4Triangular prism, colourless
F(000) = 12640.28 × 0.24 × 0.23 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
4625 independent reflections
Radiation source: fine-focus sealed tube3264 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.046
φ and ω scansθmax = 28.5°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)
h = 1212
Tmin = 0.880, Tmax = 1.00k = 2020
61378 measured reflectionsl = 3030
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)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.137H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0682P)2 + 0.4749P]
where P = (Fo2 + 2Fc2)/3
4625 reflections(Δ/σ)max < 0.001
386 parametersΔρmax = 0.27 e Å3
0 restraintsΔρmin = 0.26 e Å3
Crystal data top
C35H53N3O4V = 3281.3 (2) Å3
Mr = 579.80Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 9.2108 (4) ŵ = 0.08 mm1
b = 15.5383 (6) ÅT = 293 K
c = 22.9270 (9) Å0.28 × 0.24 × 0.23 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
4625 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)
3264 reflections with I > 2σ(I)
Tmin = 0.880, Tmax = 1.00Rint = 0.046
61378 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0470 restraints
wR(F2) = 0.137H-atom parameters constrained
S = 1.02Δρmax = 0.27 e Å3
4625 reflectionsΔρmin = 0.26 e Å3
386 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
C10.6151 (3)0.06751 (16)0.10936 (12)0.0579 (7)
H1A0.70060.10400.10920.069*
H1B0.58850.05740.14970.069*
C20.4912 (4)0.11521 (19)0.07917 (14)0.0684 (8)
H2A0.52090.13170.04020.082*
H2B0.46830.16720.10070.082*
C30.3584 (3)0.05852 (19)0.07579 (12)0.0614 (7)
H30.32800.04440.11560.074*
C40.3822 (3)0.02562 (18)0.04263 (11)0.0554 (6)
C50.5098 (3)0.07087 (16)0.07423 (10)0.0471 (5)
H50.47530.07790.11440.057*
C60.5400 (3)0.16314 (17)0.05369 (12)0.0563 (7)
H6A0.59080.16170.01660.068*
H6B0.44880.19320.04800.068*
C70.6316 (3)0.21111 (16)0.09849 (12)0.0556 (6)
H7A0.57690.21560.13450.067*
H7B0.64900.26910.08440.067*
C80.7783 (3)0.16820 (14)0.11152 (10)0.0446 (5)
C260.8744 (3)0.18187 (17)0.05709 (10)0.0548 (6)
H26A0.82040.16710.02270.082*
H26B0.95890.14590.05980.082*
H26C0.90360.24110.05500.082*
C90.7526 (3)0.07045 (14)0.12451 (9)0.0433 (5)
H90.69880.06970.16140.052*
C100.6540 (3)0.01952 (15)0.08079 (10)0.0465 (5)
C250.7321 (3)0.00105 (19)0.02266 (11)0.0613 (7)
H25A0.69600.05170.00640.092*
H25B0.83460.00400.02950.092*
H25C0.71440.04740.00410.092*
C110.8960 (3)0.02553 (15)0.13842 (11)0.0502 (6)
H11A0.87640.03380.14880.060*
H11B0.95620.02530.10370.060*
C120.9794 (3)0.06810 (16)0.18781 (11)0.0531 (6)
H12A1.07330.04050.19180.064*
H12B0.92670.06000.22400.064*
C131.0015 (3)0.16425 (15)0.17724 (10)0.0466 (5)
H131.05610.16950.14070.056*
C140.8528 (3)0.21018 (15)0.16712 (10)0.0472 (5)
C270.7567 (3)0.20149 (19)0.22234 (12)0.0619 (7)
H27A0.80410.22880.25470.093*
H27B0.74190.14170.23100.093*
H27C0.66460.22860.21550.093*
C150.8773 (4)0.30855 (15)0.15862 (13)0.0604 (7)
H15A0.92080.31780.12060.072*
H15B0.78350.33690.15860.072*
C160.9732 (4)0.35123 (18)0.20470 (13)0.0652 (8)
H16A0.98960.41090.19410.078*
H16B0.92380.35020.24200.078*
C171.1182 (3)0.30553 (16)0.21027 (11)0.0559 (6)
C181.0915 (3)0.20927 (16)0.22413 (11)0.0512 (6)
H181.03310.20790.25980.061*
C191.2424 (3)0.17477 (17)0.24085 (11)0.0565 (6)
H191.29550.16240.20480.068*
C211.3161 (4)0.2544 (2)0.27089 (16)0.0756 (9)
H21A1.33070.24350.31210.091*
H21B1.40950.26630.25310.091*
C221.2130 (4)0.3306 (2)0.26217 (14)0.0734 (9)
H22A1.15420.33980.29670.088*
H22B1.26700.38280.25390.088*
O28B1.4367 (4)0.38506 (16)0.09786 (15)0.1169 (11)
O28A1.2328 (2)0.40742 (11)0.14684 (10)0.0707 (6)
C281.2065 (4)0.31540 (16)0.15439 (13)0.0631 (8)
H28A1.29780.28460.15760.076*
H28B1.15310.29260.12140.076*
C28A1.3511 (3)0.43009 (17)0.12090 (12)0.0579 (7)
C301.1593 (5)0.0930 (3)0.33192 (15)0.1015 (13)
H30A1.05860.09140.32110.152*
H30B1.17760.14340.35500.152*
H30C1.18270.04260.35420.152*
C291.3388 (5)0.0314 (2)0.26551 (18)0.0934 (12)
H29A1.34550.01640.28970.112*
H29B1.39470.03450.23180.112*
C201.2492 (4)0.0955 (2)0.27912 (12)0.0679 (8)
N28A1.3661 (3)0.52003 (13)0.11931 (9)0.0551 (5)
C28C1.4730 (4)0.5648 (2)0.09318 (16)0.0800 (10)
H28C1.54970.54000.07290.096*
N28C1.4553 (4)0.64662 (19)0.09998 (13)0.0913 (10)
C28B1.3339 (6)0.6496 (2)0.13141 (16)0.1047 (16)
H28D1.29410.70150.14370.126*
N28B1.2732 (4)0.57561 (17)0.14415 (13)0.0927 (10)
O3A0.2407 (3)0.10679 (15)0.04757 (9)0.0766 (6)
C3A0.1539 (4)0.1536 (2)0.08194 (17)0.0746 (9)
C3B0.0438 (5)0.2023 (3)0.0477 (2)0.1178 (17)
H3B10.00810.24050.07310.177*
H3B20.09160.23500.01780.177*
H3B30.02310.16270.03000.177*
O3B0.1642 (3)0.15572 (16)0.13343 (11)0.0893 (7)
C230.2444 (4)0.0802 (2)0.04879 (15)0.0751 (9)
H23A0.16170.04700.03670.113*
H23B0.25250.13050.02470.113*
H23C0.23260.09720.08880.113*
C240.4052 (4)0.0100 (2)0.02329 (11)0.0722 (9)
H24A0.47410.03570.02870.108*
H24B0.44130.06160.04110.108*
H24C0.31450.00570.04100.108*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0710 (18)0.0417 (12)0.0609 (14)0.0054 (13)0.0163 (14)0.0070 (11)
C20.081 (2)0.0515 (15)0.0729 (18)0.0131 (16)0.0204 (17)0.0042 (13)
C30.0663 (18)0.0673 (17)0.0506 (13)0.0177 (15)0.0091 (13)0.0030 (12)
C40.0584 (16)0.0628 (16)0.0450 (12)0.0015 (14)0.0051 (12)0.0002 (11)
C50.0529 (14)0.0493 (13)0.0391 (11)0.0029 (12)0.0007 (11)0.0023 (10)
C60.0595 (17)0.0511 (15)0.0585 (14)0.0087 (13)0.0062 (13)0.0123 (12)
C70.0610 (16)0.0405 (12)0.0653 (15)0.0070 (13)0.0060 (14)0.0056 (11)
C80.0538 (15)0.0354 (11)0.0446 (11)0.0047 (10)0.0025 (11)0.0067 (9)
C260.0673 (17)0.0485 (13)0.0486 (12)0.0040 (13)0.0025 (13)0.0091 (11)
C90.0534 (14)0.0369 (10)0.0395 (10)0.0001 (11)0.0002 (10)0.0067 (8)
C100.0555 (14)0.0405 (11)0.0435 (11)0.0016 (11)0.0033 (11)0.0037 (10)
C250.0696 (19)0.0622 (16)0.0521 (13)0.0051 (15)0.0017 (13)0.0098 (12)
C110.0582 (15)0.0324 (11)0.0599 (13)0.0004 (11)0.0062 (13)0.0073 (10)
C120.0591 (16)0.0415 (12)0.0588 (14)0.0021 (12)0.0110 (12)0.0105 (11)
C130.0557 (15)0.0379 (11)0.0460 (12)0.0008 (11)0.0006 (11)0.0022 (9)
C140.0564 (15)0.0370 (11)0.0483 (12)0.0012 (11)0.0037 (12)0.0003 (9)
C270.0609 (17)0.0701 (18)0.0546 (14)0.0003 (15)0.0088 (14)0.0073 (13)
C150.0696 (19)0.0367 (12)0.0749 (17)0.0053 (13)0.0024 (15)0.0028 (11)
C160.076 (2)0.0424 (13)0.0772 (18)0.0000 (15)0.0019 (16)0.0104 (13)
C170.0673 (17)0.0403 (12)0.0601 (14)0.0046 (13)0.0043 (14)0.0102 (11)
C180.0617 (16)0.0449 (13)0.0472 (12)0.0054 (12)0.0026 (12)0.0011 (10)
C190.0613 (16)0.0541 (14)0.0542 (13)0.0044 (13)0.0046 (13)0.0018 (11)
C210.075 (2)0.0687 (19)0.083 (2)0.0126 (17)0.0129 (18)0.0126 (16)
C220.084 (2)0.0630 (17)0.0735 (18)0.0137 (17)0.0030 (17)0.0216 (15)
O28B0.115 (2)0.0569 (14)0.178 (3)0.0232 (15)0.069 (2)0.0178 (16)
O28A0.0707 (14)0.0390 (9)0.1026 (15)0.0049 (9)0.0170 (12)0.0013 (9)
C280.077 (2)0.0369 (12)0.0758 (18)0.0084 (13)0.0056 (15)0.0017 (12)
C28A0.0659 (18)0.0434 (13)0.0644 (15)0.0007 (14)0.0034 (14)0.0015 (12)
C300.109 (3)0.129 (3)0.0663 (19)0.016 (3)0.009 (2)0.029 (2)
C290.114 (3)0.071 (2)0.095 (3)0.005 (2)0.026 (2)0.0128 (19)
C200.078 (2)0.0687 (18)0.0573 (15)0.0102 (17)0.0224 (15)0.0064 (13)
N28A0.0686 (15)0.0433 (11)0.0534 (11)0.0037 (11)0.0010 (11)0.0030 (9)
C28C0.077 (2)0.069 (2)0.095 (2)0.0130 (19)0.0108 (19)0.0151 (17)
N28C0.129 (3)0.0584 (16)0.0869 (19)0.0260 (19)0.008 (2)0.0077 (14)
C28B0.184 (5)0.0436 (16)0.087 (2)0.004 (2)0.043 (3)0.0026 (15)
N28B0.132 (3)0.0465 (13)0.099 (2)0.0014 (17)0.050 (2)0.0007 (14)
O3A0.0812 (15)0.0842 (15)0.0645 (12)0.0263 (13)0.0180 (12)0.0007 (11)
C3A0.074 (2)0.0611 (18)0.088 (2)0.0109 (17)0.0110 (19)0.0049 (17)
C3B0.117 (4)0.106 (3)0.130 (3)0.053 (3)0.046 (3)0.017 (3)
O3B0.0966 (18)0.0872 (16)0.0840 (16)0.0238 (15)0.0001 (14)0.0063 (13)
C230.0578 (18)0.084 (2)0.083 (2)0.0057 (18)0.0044 (17)0.0024 (17)
C240.078 (2)0.093 (2)0.0453 (13)0.0016 (19)0.0126 (14)0.0007 (14)
Geometric parameters (Å, º) top
C1—C21.527 (4)C15—H15A0.9700
C1—C101.545 (3)C15—H15B0.9700
C1—H1A0.9700C16—C171.518 (4)
C1—H1B0.9700C16—H16A0.9700
C2—C31.510 (4)C16—H16B0.9700
C2—H2A0.9700C17—C281.525 (4)
C2—H2B0.9700C17—C221.526 (4)
C3—O3A1.468 (3)C17—C181.549 (3)
C3—C41.528 (4)C18—C191.538 (4)
C3—H30.9800C18—H180.9800
C4—C231.533 (4)C19—C201.514 (4)
C4—C241.545 (4)C19—C211.570 (4)
C4—C51.550 (4)C19—H190.9800
C5—C61.534 (4)C21—C221.530 (5)
C5—C101.557 (3)C21—H21A0.9700
C5—H50.9800C21—H21B0.9700
C6—C71.524 (4)C22—H22A0.9700
C6—H6A0.9700C22—H22B0.9700
C6—H6B0.9700O28B—C28A1.179 (4)
C7—C81.536 (4)O28A—C28A1.290 (3)
C7—H7A0.9700O28A—C281.461 (3)
C7—H7B0.9700C28—H28A0.9700
C8—C261.545 (3)C28—H28B0.9700
C8—C91.566 (3)C28A—N28A1.405 (3)
C8—C141.588 (3)C30—C201.467 (5)
C26—H26A0.9600C30—H30A0.9600
C26—H26B0.9600C30—H30B0.9600
C26—H26C0.9600C30—H30C0.9600
C9—C111.528 (3)C29—C201.330 (5)
C9—C101.567 (3)C29—H29A0.9300
C9—H90.9800C29—H29B0.9300
C10—C251.541 (4)N28A—N28B1.343 (3)
C25—H25A0.9600N28A—C28C1.346 (4)
C25—H25B0.9600C28C—N28C1.292 (5)
C25—H25C0.9600C28C—H28C0.9300
C11—C121.520 (3)N28C—C28B1.331 (6)
C11—H11A0.9700C28B—N28B1.311 (4)
C11—H11B0.9700C28B—H28D0.9300
C12—C131.527 (3)O3A—C3A1.337 (4)
C12—H12A0.9700C3A—O3B1.185 (4)
C12—H12B0.9700C3A—C3B1.489 (5)
C13—C181.527 (3)C3B—H3B10.9600
C13—C141.562 (4)C3B—H3B20.9600
C13—H130.9800C3B—H3B30.9600
C14—C271.551 (4)C23—H23A0.9600
C14—C151.557 (3)C23—H23B0.9600
C27—H27A0.9600C23—H23C0.9600
C27—H27B0.9600C24—H24A0.9600
C27—H27C0.9600C24—H24B0.9600
C15—C161.529 (4)C24—H24C0.9600
C2—C1—C10114.0 (2)C16—C15—C14115.0 (2)
C2—C1—H1A108.8C16—C15—H15A108.5
C10—C1—H1A108.8C14—C15—H15A108.5
C2—C1—H1B108.8C16—C15—H15B108.5
C10—C1—H1B108.8C14—C15—H15B108.5
H1A—C1—H1B107.7H15A—C15—H15B107.5
C3—C2—C1110.2 (2)C17—C16—C15111.3 (2)
C3—C2—H2A109.6C17—C16—H16A109.4
C1—C2—H2A109.6C15—C16—H16A109.4
C3—C2—H2B109.6C17—C16—H16B109.4
C1—C2—H2B109.6C15—C16—H16B109.4
H2A—C2—H2B108.1H16A—C16—H16B108.0
O3A—C3—C2108.8 (2)C16—C17—C28110.6 (2)
O3A—C3—C4108.9 (2)C16—C17—C22116.7 (2)
C2—C3—C4114.1 (2)C28—C17—C22108.9 (2)
O3A—C3—H3108.3C16—C17—C18109.2 (2)
C2—C3—H3108.3C28—C17—C18110.7 (2)
C4—C3—H3108.3C22—C17—C18100.2 (2)
C3—C4—C23108.0 (2)C13—C18—C19120.4 (2)
C3—C4—C24111.8 (2)C13—C18—C17112.6 (2)
C23—C4—C24106.9 (2)C19—C18—C17104.1 (2)
C3—C4—C5105.3 (2)C13—C18—H18106.3
C23—C4—C5109.5 (2)C19—C18—H18106.3
C24—C4—C5115.1 (2)C17—C18—H18106.3
C6—C5—C4114.7 (2)C20—C19—C18117.7 (3)
C6—C5—C10110.7 (2)C20—C19—C21111.7 (2)
C4—C5—C10117.4 (2)C18—C19—C21103.0 (2)
C6—C5—H5104.1C20—C19—H19108.0
C4—C5—H5104.1C18—C19—H19108.0
C10—C5—H5104.1C21—C19—H19108.0
C7—C6—C5110.5 (2)C22—C21—C19106.5 (2)
C7—C6—H6A109.5C22—C21—H21A110.4
C5—C6—H6A109.5C19—C21—H21A110.4
C7—C6—H6B109.5C22—C21—H21B110.4
C5—C6—H6B109.5C19—C21—H21B110.4
H6A—C6—H6B108.1H21A—C21—H21B108.6
C6—C7—C8113.9 (2)C17—C22—C21105.0 (2)
C6—C7—H7A108.8C17—C22—H22A110.7
C8—C7—H7A108.8C21—C22—H22A110.7
C6—C7—H7B108.8C17—C22—H22B110.7
C8—C7—H7B108.8C21—C22—H22B110.7
H7A—C7—H7B107.7H22A—C22—H22B108.8
C7—C8—C26106.7 (2)C28A—O28A—C28117.5 (2)
C7—C8—C9109.0 (2)O28A—C28—C17106.6 (2)
C26—C8—C9111.94 (19)O28A—C28—H28A110.4
C7—C8—C14110.99 (19)C17—C28—H28A110.4
C26—C8—C14110.1 (2)O28A—C28—H28B110.4
C9—C8—C14108.12 (17)C17—C28—H28B110.4
C8—C26—H26A109.5H28A—C28—H28B108.6
C8—C26—H26B109.5O28B—C28A—O28A127.5 (3)
H26A—C26—H26B109.5O28B—C28A—N28A120.8 (3)
C8—C26—H26C109.5O28A—C28A—N28A111.5 (3)
H26A—C26—H26C109.5C20—C30—H30A109.5
H26B—C26—H26C109.5C20—C30—H30B109.5
C11—C9—C8110.6 (2)H30A—C30—H30B109.5
C11—C9—C10113.82 (19)C20—C30—H30C109.5
C8—C9—C10117.10 (18)H30A—C30—H30C109.5
C11—C9—H9104.6H30B—C30—H30C109.5
C8—C9—H9104.6C20—C29—H29A120.0
C10—C9—H9104.6C20—C29—H29B120.0
C25—C10—C1108.2 (2)H29A—C29—H29B120.0
C25—C10—C5114.2 (2)C29—C20—C30121.6 (3)
C1—C10—C5107.0 (2)C29—C20—C19119.9 (3)
C25—C10—C9112.1 (2)C30—C20—C19118.4 (3)
C1—C10—C9107.77 (18)N28B—N28A—C28C108.8 (3)
C5—C10—C9107.30 (19)N28B—N28A—C28A124.5 (3)
C10—C25—H25A109.5C28C—N28A—C28A126.7 (3)
C10—C25—H25B109.5N28C—C28C—N28A111.3 (3)
H25A—C25—H25B109.5N28A—C28C—C28B71.5 (2)
C10—C25—H25C109.5N28C—C28C—H28C124.4
H25A—C25—H25C109.5N28A—C28C—H28C124.4
H25B—C25—H25C109.5C28B—C28C—H28C164.2
C12—C11—C9113.2 (2)C28C—N28C—C28B101.8 (3)
C12—C11—H11A108.9N28B—C28B—N28C116.7 (3)
C9—C11—H11A108.9N28B—C28B—C28C78.3 (2)
C12—C11—H11B108.9N28B—C28B—H28D121.7
C9—C11—H11B108.9N28C—C28B—H28D121.7
H11A—C11—H11B107.8C28C—C28B—H28D160.0
C11—C12—C13112.0 (2)C28B—N28B—N28A101.4 (3)
C11—C12—H12A109.2C3A—O3A—C3117.3 (2)
C13—C12—H12A109.2O3B—C3A—O3A123.7 (3)
C11—C12—H12B109.2O3B—C3A—C3B124.5 (4)
C13—C12—H12B109.2O3A—C3A—C3B111.9 (3)
H12A—C12—H12B107.9C3A—C3B—H3B1109.5
C18—C13—C12114.1 (2)C3A—C3B—H3B2109.5
C18—C13—C14111.80 (19)H3B1—C3B—H3B2109.5
C12—C13—C14110.7 (2)C3A—C3B—H3B3109.5
C18—C13—H13106.6H3B1—C3B—H3B3109.5
C12—C13—H13106.6H3B2—C3B—H3B3109.5
C14—C13—H13106.6C4—C23—H23A109.5
C27—C14—C15105.7 (2)C4—C23—H23B109.5
C27—C14—C13109.8 (2)H23A—C23—H23B109.5
C15—C14—C13109.9 (2)C4—C23—H23C109.5
C27—C14—C8111.9 (2)H23A—C23—H23C109.5
C15—C14—C8111.42 (19)H23B—C23—H23C109.5
C13—C14—C8108.10 (18)C4—C24—H24A109.5
C14—C27—H27A109.5C4—C24—H24B109.5
C14—C27—H27B109.5H24A—C24—H24B109.5
H27A—C27—H27B109.5C4—C24—H24C109.5
C14—C27—H27C109.5H24A—C24—H24C109.5
H27A—C27—H27C109.5H24B—C24—H24C109.5
H27B—C27—H27C109.5
C10—C1—C2—C355.5 (3)C26—C8—C14—C1361.4 (2)
C1—C2—C3—O3A179.0 (2)C9—C8—C14—C1361.2 (2)
C1—C2—C3—C459.2 (3)C27—C14—C15—C1669.1 (3)
O3A—C3—C4—C2364.5 (3)C13—C14—C15—C1649.3 (3)
C2—C3—C4—C23173.7 (2)C8—C14—C15—C16169.1 (2)
O3A—C3—C4—C2452.9 (3)C14—C15—C16—C1754.0 (3)
C2—C3—C4—C2468.9 (3)C15—C16—C17—C2865.9 (3)
O3A—C3—C4—C5178.6 (2)C15—C16—C17—C22168.9 (2)
C2—C3—C4—C556.8 (3)C15—C16—C17—C1856.2 (3)
C3—C4—C5—C6171.9 (2)C12—C13—C18—C1953.6 (3)
C23—C4—C5—C656.1 (3)C14—C13—C18—C19179.8 (2)
C24—C4—C5—C664.4 (3)C12—C13—C18—C17177.0 (2)
C3—C4—C5—C1055.5 (3)C14—C13—C18—C1756.3 (3)
C23—C4—C5—C10171.3 (2)C16—C17—C18—C1359.0 (3)
C24—C4—C5—C1068.2 (3)C28—C17—C18—C1363.0 (3)
C4—C5—C6—C7162.3 (2)C22—C17—C18—C13177.9 (2)
C10—C5—C6—C762.0 (3)C16—C17—C18—C19168.9 (2)
C5—C6—C7—C858.4 (3)C28—C17—C18—C1969.1 (3)
C6—C7—C8—C2671.6 (3)C22—C17—C18—C1945.8 (3)
C6—C7—C8—C949.5 (3)C13—C18—C19—C2076.5 (3)
C6—C7—C8—C14168.4 (2)C17—C18—C19—C20156.1 (2)
C7—C8—C9—C11179.3 (2)C13—C18—C19—C21160.1 (2)
C26—C8—C9—C1162.9 (3)C17—C18—C19—C2132.7 (3)
C14—C8—C9—C1158.6 (2)C20—C19—C21—C22134.6 (3)
C7—C8—C9—C1048.0 (3)C18—C19—C21—C227.3 (3)
C26—C8—C9—C1069.8 (3)C16—C17—C22—C21158.4 (3)
C14—C8—C9—C10168.74 (19)C28—C17—C22—C2175.6 (3)
C2—C1—C10—C2572.6 (3)C18—C17—C22—C2140.7 (3)
C2—C1—C10—C550.9 (3)C19—C21—C22—C1721.1 (3)
C2—C1—C10—C9166.0 (2)C28A—O28A—C28—C17149.6 (3)
C6—C5—C10—C2567.9 (3)C16—C17—C28—O28A61.9 (3)
C4—C5—C10—C2566.5 (3)C22—C17—C28—O28A67.6 (3)
C6—C5—C10—C1172.46 (19)C18—C17—C28—O28A176.9 (2)
C4—C5—C10—C153.2 (3)C28—O28A—C28A—O28B6.8 (5)
C6—C5—C10—C957.0 (2)C28—O28A—C28A—N28A176.9 (2)
C4—C5—C10—C9168.60 (19)C18—C19—C20—C29133.8 (3)
C11—C9—C10—C2557.1 (3)C21—C19—C20—C29107.4 (3)
C8—C9—C10—C2574.1 (3)C18—C19—C20—C3048.4 (4)
C11—C9—C10—C161.8 (3)C21—C19—C20—C3070.5 (4)
C8—C9—C10—C1167.0 (2)O28B—C28A—N28A—N28B179.7 (3)
C11—C9—C10—C5176.71 (18)O28A—C28A—N28A—N28B3.1 (4)
C8—C9—C10—C552.1 (3)O28B—C28A—N28A—C28C0.1 (5)
C8—C9—C11—C1254.8 (3)O28A—C28A—N28A—C28C176.6 (3)
C10—C9—C11—C12170.86 (19)N28B—N28A—C28C—N28C0.4 (4)
C9—C11—C12—C1353.1 (3)C28A—N28A—C28C—N28C179.8 (3)
C11—C12—C13—C18177.0 (2)N28B—N28A—C28C—C28B0.6 (3)
C11—C12—C13—C1455.8 (3)C28A—N28A—C28C—C28B179.6 (3)
C18—C13—C14—C2766.3 (3)N28A—C28C—N28C—C28B0.2 (4)
C12—C13—C14—C2762.2 (3)C28C—N28C—C28B—N28B0.9 (5)
C18—C13—C14—C1549.6 (3)N28C—C28C—C28B—N28B179.2 (5)
C12—C13—C14—C15178.0 (2)N28A—C28C—C28B—N28B0.6 (3)
C18—C13—C14—C8171.36 (18)N28A—C28C—C28B—N28C179.8 (4)
C12—C13—C14—C860.2 (2)N28C—C28B—N28B—N28A1.1 (5)
C7—C8—C14—C2759.5 (3)C28C—C28B—N28B—N28A0.6 (3)
C26—C8—C14—C27177.5 (2)C28C—N28A—N28B—C28B0.9 (4)
C9—C8—C14—C2759.9 (3)C28A—N28A—N28B—C28B179.3 (3)
C7—C8—C14—C1558.5 (3)C2—C3—O3A—C3A89.2 (3)
C26—C8—C14—C1559.4 (3)C4—C3—O3A—C3A145.8 (3)
C9—C8—C14—C15178.0 (2)C3—O3A—C3A—O3B2.5 (5)
C7—C8—C14—C13179.37 (19)C3—O3A—C3A—C3B177.4 (3)

Experimental details

Crystal data
Chemical formulaC35H53N3O4
Mr579.80
Crystal system, space groupOrthorhombic, P212121
Temperature (K)293
a, b, c (Å)9.2108 (4), 15.5383 (6), 22.9270 (9)
V3)3281.3 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.28 × 0.24 × 0.23
Data collection
DiffractometerBruker APEXII CCD area-detector
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2000)
Tmin, Tmax0.880, 1.00
No. of measured, independent and
observed [I > 2σ(I)] reflections
61378, 4625, 3264
Rint0.046
(sin θ/λ)max1)0.671
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.137, 1.02
No. of reflections4625
No. of parameters386
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.27, 0.26

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

 

Acknowledgements

This work was supported by the Fundação para a Ciência e Tecnologia. RCS thanks the FCT for a grant (No. SFRH/BD/23700/2005). We gratefully acknowledge LCA-UC for the grant of computer time in the Milipeia cluster, and Mr Carlos Pereira for help in the analysis of the output of the GAMESS code.

References

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