Tetra­hydro­alstonine

Cachet, X.; Porée, F.-H.; Michel, S.; Lemoine, P.

doi:10.1107/S1600536813021168

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 69| Part 9| September 2013| Pages o1389-o1390

doi:10.1107/S1600536813021168

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Tetrahydroalstonine

Xavier Cachet,^a François-Hugues Porée,^a ^* Sylvie Michel ^a and Pascale Lemoine ^b

^aLaboratoire de Pharmacognosie, UMR CNRS 8638, Faculté des Sciences Pharmaceutiques et Biologiques de Paris Descartes, 4, avenue de l'Observatoire, 75270 Paris Cedex 06, France, and ^bLaboratoire de Cristallographie et RMN biologiques, UMR CNRS 8015, Faculté des Sciences Pharmaceutiques et Biologiques de Paris Descartes, 4, avenue de l'Observatoire, 75270 Paris Cedex 06, France
^*Correspondence e-mail: francois-hugues.poree@parisdescartes.fr

(Received 1 July 2013; accepted 29 July 2013; online 7 August 2013)

In the title compound, C₂₁H₂₄N₂O₃ [systematic name: methyl (20α)-16,17-didehydro-19α-methyl-18-oxayohimban-16-carboxylate], the molecule adopts an L-type conformation. The crystal packing is governed by one N—H⋯π and one C—H⋯π interactions. The crystal cohesion is ensured by intermolecular van der Waals contacts [shortest O⋯O contact = 3.199 (2) Å].

Related literature

For the extraction of tetrahydroalstonine (THA) from natural sources, see: Zenk & Juenger (2007 ); Mandal et al. (1983 ); Langlois et al. (1979 ). For stereochemistry studies, see: Wenkert et al. (1961 ); Wenkert & Roychaudhuri (1957 ); Shamma & Richey (1963 ); Lounasmaa & Kan (1980 ); Höfle et al. (1980 ). For the semisynthesis, see: Poirot (2007 ); Beziat & Hatinguais (1977 ); Zsadon et al. (1979 ); Guéritte et al. (1983 ); Hemscheidt & Zenk (1985 ) and for synthetic studies, see: Gutzwiller et al. (1971 ); Wenkert et al. (1976 ); Zou et al. (2010 ). For the biological activity of TMA, see Zou et al. (2010); Sharma et al. (1988 ). For a related structure, see: Laus & Wurst (2008 ).

Experimental

Crystal data

C₂₁H₂₄N₂O₃
M_r = 352.42
Orthorhombic, P 2₁ 2₁ 2₁
a = 6.719 (1) Å
b = 8.169 (2) Å
c = 34.120 (5) Å
V = 1872.8 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 293 K
0.50 × 0.30 × 0.10 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan (COLLECT; Nonius, 2004 ) T_min = 0.982, T_max = 0.992
3300 measured reflections
3300 independent reflections
2537 reflections with I > 2σ(I)

Refinement

R[F² > 2σ(F²)] = 0.044
wR(F²) = 0.114
S = 1.01
3300 reflections
247 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.11 e Å⁻³
Δρ_min = −0.12 e Å⁻³
Absolute structure parameter: −0.3 (17)

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the C8–C13 and C2/C7/C8/C13/N1 rings, respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯Cg1ⁱ	0.86	2.85	3.550 (2)	139
C6—H6A⋯Cg2ⁱⁱ	0.97	2.8	3.429 (3)	121
Symmetry codes: (i) $[-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) $[-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: COLLECT (Nonius, 2004); cell refinement: SCALEPACK (Otwinowski & Minor, 1997 ); data reduction: DENZO (Otwinowski & Minor, 1997) and SCALEPACK; program(s) used to solve structure: SIR92 (Altomare et al., 1994 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ); software used to prepare material for publication: WinGX (Farrugia, 2012).

Supporting information

Crystal structure: contains datablock I. DOI: 10.1107/S1600536813021168/bq2388sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813021168/bq2388Isup2.hkl

checkCIF report

Comment top

Tetrahydroalstonine (THA) is an indolomonoterpenoid alkaloid possessing a 5-fused ring corynanthean type skeleton (Höfle et al. 1980; Zenk & Juenger 2007). Depending on the stereochemistry at the positions C3, C15, C19 and C20, several subgroups of corynanthe alkaloids have been distinguished (Lounasmaa & Kan, 1980). THA belongs to the alloheteroyohimbine subgroup together with rauniticine (Shamma & Richey 1963). Its distribution is restricted to plants belonging to the sole plants of the Apocynaceae, Rubiaceae and Loganiaceae families. THA constitutes the main by-product of the marketed drug raubasine (ajmalicine) industrial production (Poirot 2007; Beziat & Hatinguais 1977; Zsadon et al. 1979). Indeed, this molecule is readily available in a large amount by the reduction with NaBH₄ of serpentine present in the underground parts of Catharanthus roseus (Mandal et al. 1983). This reaction directly carried out on a total alkaloid extract also affords THA resulting from alstonine reduction. Furthermore, this method followed by the isolation of THA and raubasine has been employed for a convenient determination of the alstonine and serpentine respective content in the aerial parts of Catharanthus ovalis (Langlois et al. 1979). The structure of THA has been elucidated after extensive NMR studies during the period 1950–1960 (Wenkert & Roychaudhuri 1957; Wenkert et al. 1961). In the corynanthe series, only the crystal structure of akuammigine (as picrate hydrate) has been previously reported (Laus & Wurst 2008). There have been only a few reports of the THA biological activities (Zou et al. 2010; Sharma et al. 1988). The X-ray data of THA confirmed the relative allo configuration of the C3, C15, C19 and C20 stereocenters. With reference of the known (15S)- configuration due to the biosynthesis, the absolute configuration of the other stereocenters is thus given by (3S, 19S, 20S). The aromatic rings A (C8-C13) and B (C2/C7/C8/C13/N1) are planar. Ring C (C2/C3/N4/C5-C7) adopts a half-chair conformation with N4 above the medium A/B plane by 0.437 (4) Å and C5 below the medium A/B plane by 0.334 (4) Å, respectively. The C/D ring is a trans-fused quinolizidine. Ring D (C3/C14/C15/C20/C21/N4) is a regular chair with H—C3 α axial. The D/E rings are cis-fused; H—C15 and H—C20 are α, the first one being in axial position and the second in equatorial. Ring E (C15-C20) is a half-chair with C19 above the median plan (C15—C16—C17—O18) by -0.273 (5) Å and C20 below the same plan by 0.497 (4) Å. The α Me—C19 group adopts a pseudoequatorial position (Figure 1.). The crystal packing of the compound is governed by one N—H···Cg (π ring, Cg centroid of ring A) interaction and one C—H···Cg (π ring, Cg centroid of ring B) interaction. The crystal cohesion is ensured by intermolecular van der Waals contacts, the shortest is equal to 3.199 (2) Å for O18 and O24.

Related literature top

For the extraction of tetrahydroalstonine (THA) from natural sources, see: Zenk & Juenger (2007); Mandal et al. (1983); Langlois et al. (1979). For stereochemistry studies, see: Wenkert et al. (1961); Wenkert & Roychaudhuri (1957); Shamma & Richey (1963); Lounasmaa & Kan (1980); Höfle et al. (1980). For the semisynthesis, see: Poirot (2007); Beziat & Hatinguais (1977); Zsadon et al. (1979); Guéritte et al. (1983); Hemscheidt & Zenk (1985) and for synthetic studies, see: Gutzwiller et al. (1971); Wenkert et al. (1976); Zou et al. (2010). For the biological activity of TMA, see Zou et al. (2010); Sharma et al. (1988). For a related structure, see: Laus & Wurst (2008).

Experimental top

The typical conditions used for the semi-synthesis were followed. The pulverized dried roots of Catharanthus roseus (20.0 g) were extracted overnight with a (1:1) mixture of CH₂Cl₂/MeOH. After filtration and solvent removal, the alkaloid extract was dissolved in MeOH and NaBH₄ (500 mg) was slowly added at 0°C. After completion of the reduction (TLC control), water was added and the solution was extracted with CH₂Cl₂ (alkaloids were monitored with the Dragendorff reagent). The combined organic layers were dried over MgSO₄, filtered and concentrated in vacuo. The residue was purified by chromatography on silica gel (Eluent CH₂Cl₂/MeOH 99/1) to give THA and raubasine as white powders. The former was crystallized from MeOH to give THA as colorless plates suitable for X-ray diffraction.

Computing details top

Data collection: COLLECT (Nonius, 2004); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top

Fig. 1. Molecular view of the compound showing atomic numbering. Displacements ellipsoids at the 50% probability level.

Methyl (20α)-16,17-didehydro-19α-methyl-18-oxayohimban-16-carboxylate top

Crystal data top

C₂₁H₂₄N₂O₃	F(000) = 752
M_r = 352.42	D_x = 1.250 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: P 2ac 2ab	Cell parameters from 1924 reflections
a = 6.719 (1) Å	θ = 0.4–25.4°
b = 8.169 (2) Å	µ = 0.08 mm⁻¹
c = 34.120 (5) Å	T = 293 K
V = 1872.8 (6) Å³	Parallelepiped, colourless
Z = 4	0.50 × 0.30 × 0.10 mm

Data collection top

Nonius KappaCCD diffractometer	3300 independent reflections
Radiation source: fine-focus sealed tube	2537 reflections with I > 2σ(I)
Horizonally mounted graphite crystal monochromator	R_int = 0.000
Detector resolution: 9 pixels mm^-1	θ_max = 25.3°, θ_min = 3.5°
CCD scans	h = −8→8
Absorption correction: multi-scan (COLLECT; Nonius, 2004)	k = −9→9
T_min = 0.982, T_max = 0.992	l = −40→40
3300 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.114	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	w = 1/[σ²(F_o²) + (0.0585P)² + 0.175P] where P = (F_o² + 2F_c²)/3
3300 reflections	(Δ/σ)_max < 0.001
247 parameters	Δρ_max = 0.11 e Å⁻³
0 restraints	Δρ_min = −0.12 e Å⁻³

Crystal data top

C₂₁H₂₄N₂O₃	V = 1872.8 (6) Å³
M_r = 352.42	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 6.719 (1) Å	µ = 0.08 mm⁻¹
b = 8.169 (2) Å	T = 293 K
c = 34.120 (5) Å	0.50 × 0.30 × 0.10 mm

Data collection top

Nonius KappaCCD diffractometer	3300 independent reflections
Absorption correction: multi-scan (COLLECT; Nonius, 2004)	2537 reflections with I > 2σ(I)
T_min = 0.982, T_max = 0.992	R_int = 0.000
3300 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.044	0 restraints
wR(F²) = 0.114	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	Δρ_max = 0.11 e Å⁻³
3300 reflections	Δρ_min = −0.12 e Å⁻³
247 parameters

Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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

	x	y	z	U_iso*/U_eq
N1	0.0941 (2)	1.03273 (19)	0.22093 (5)	0.0543 (4)
H1	0.0106	1.0929	0.2084	0.065*
C2	0.2643 (3)	0.9635 (2)	0.20539 (6)	0.0498 (4)
C3	0.3268 (3)	0.9745 (3)	0.16349 (6)	0.0554 (5)
H3	0.388 (3)	1.082 (3)	0.1594 (6)	0.072 (6)*
N4	0.4687 (2)	0.8412 (2)	0.15597 (6)	0.0661 (5)
C5	0.6291 (3)	0.8379 (3)	0.18547 (8)	0.0769 (7)
H5A	0.6887	0.9457	0.1874	0.092*
H5B	0.7315	0.7616	0.1772	0.092*
C6	0.5502 (3)	0.7872 (3)	0.22502 (8)	0.0703 (6)
H6A	0.5248	0.6704	0.2252	0.084*
H6B	0.6483	0.8111	0.2451	0.084*
C7	0.3616 (3)	0.8781 (2)	0.23357 (6)	0.0560 (5)
C8	0.2480 (3)	0.8919 (2)	0.26876 (6)	0.0561 (5)
C9	0.2699 (4)	0.8333 (3)	0.30708 (7)	0.0713 (6)
H9	0.3806	0.7713	0.3139	0.086*
C10	0.1262 (5)	0.8682 (3)	0.33441 (8)	0.0834 (8)
H10	0.1396	0.8284	0.3598	0.100*
C11	−0.0392 (5)	0.9624 (3)	0.32467 (7)	0.0834 (7)
H11	−0.1357	0.9828	0.3436	0.100*
C12	−0.0628 (4)	1.0259 (3)	0.28766 (6)	0.0701 (6)
H12	−0.1717	1.0912	0.2815	0.084*
C13	0.0803 (3)	0.9893 (2)	0.25995 (6)	0.0542 (5)
C14	0.1540 (3)	0.9621 (3)	0.13484 (5)	0.0536 (5)
H14A	0.0620	1.0515	0.1395	0.064*
H14B	0.0834	0.8602	0.1392	0.064*
C15	0.2267 (4)	0.9687 (3)	0.09227 (6)	0.0640 (6)
H15	0.281 (4)	1.076 (3)	0.0888 (7)	0.073 (7)*
C16	0.0636 (4)	0.9412 (3)	0.06288 (6)	0.0662 (6)
C17	0.0518 (5)	0.8003 (3)	0.04332 (7)	0.0847 (8)
H17	−0.0469	0.7924	0.0243	0.102*
O18	0.1678 (3)	0.6694 (2)	0.04839 (6)	0.1032 (7)
C19	0.3020 (5)	0.6744 (3)	0.08207 (8)	0.0872 (8)
H19	0.2254	0.6518	0.1059	0.105*
C20	0.3918 (4)	0.8443 (3)	0.08520 (8)	0.0797 (7)
H20	0.465 (4)	0.871 (3)	0.0595 (7)	0.088 (7)*
C21	0.5520 (4)	0.8600 (4)	0.11650 (8)	0.0887 (8)
H21A	0.6530	0.7770	0.1122	0.106*
H21B	0.6151	0.9664	0.1143	0.106*
C22	0.4475 (7)	0.5356 (4)	0.07534 (11)	0.1426 (15)
H22A	0.5421	0.5670	0.0556	0.214*
H22B	0.3765	0.4401	0.0668	0.214*
H22C	0.5162	0.5117	0.0993	0.214*
C23	−0.0746 (4)	1.0739 (3)	0.05479 (6)	0.0695 (6)
O24	−0.2128 (3)	1.0354 (2)	0.02800 (5)	0.0910 (6)
O25	−0.0672 (3)	1.2070 (2)	0.06996 (5)	0.0945 (6)
C26	−0.3520 (5)	1.1602 (4)	0.01729 (10)	0.1060 (10)
H26A	−0.2815	1.2528	0.0069	0.159*
H26B	−0.4264	1.1930	0.0400	0.159*
H26C	−0.4414	1.1184	−0.0023	0.159*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0552 (9)	0.0540 (8)	0.0537 (9)	0.0087 (8)	−0.0107 (8)	−0.0008 (8)
C2	0.0463 (10)	0.0450 (9)	0.0581 (11)	0.0012 (9)	−0.0105 (9)	−0.0051 (8)
C3	0.0481 (11)	0.0531 (11)	0.0651 (13)	−0.0025 (10)	−0.0025 (9)	−0.0021 (10)
N4	0.0456 (9)	0.0757 (12)	0.0770 (13)	0.0066 (9)	0.0038 (9)	−0.0051 (9)
C5	0.0452 (12)	0.0821 (16)	0.103 (2)	0.0048 (12)	−0.0055 (13)	−0.0034 (15)
C6	0.0513 (12)	0.0617 (12)	0.0980 (18)	0.0078 (11)	−0.0201 (13)	−0.0022 (12)
C7	0.0530 (11)	0.0462 (10)	0.0687 (14)	0.0017 (9)	−0.0153 (10)	−0.0056 (9)
C8	0.0641 (12)	0.0417 (9)	0.0625 (13)	−0.0021 (10)	−0.0205 (11)	−0.0017 (9)
C9	0.0917 (17)	0.0530 (12)	0.0691 (15)	−0.0038 (13)	−0.0249 (14)	0.0064 (11)
C10	0.125 (2)	0.0657 (14)	0.0599 (15)	−0.0183 (17)	−0.0172 (16)	0.0068 (11)
C11	0.115 (2)	0.0756 (14)	0.0595 (14)	−0.0120 (18)	0.0064 (14)	−0.0098 (12)
C12	0.0783 (15)	0.0660 (12)	0.0661 (14)	0.0020 (13)	−0.0016 (12)	−0.0122 (11)
C13	0.0597 (11)	0.0488 (10)	0.0540 (11)	0.0013 (9)	−0.0095 (9)	−0.0051 (8)
C14	0.0508 (11)	0.0587 (11)	0.0512 (11)	0.0008 (10)	0.0007 (9)	−0.0045 (9)
C15	0.0718 (15)	0.0622 (12)	0.0579 (12)	−0.0037 (13)	0.0122 (11)	0.0005 (10)
C16	0.0851 (16)	0.0686 (14)	0.0451 (11)	−0.0008 (13)	0.0087 (11)	0.0000 (10)
C17	0.116 (2)	0.0844 (17)	0.0538 (14)	0.0096 (18)	−0.0026 (14)	−0.0102 (12)
O18	0.1444 (18)	0.0837 (12)	0.0815 (13)	0.0226 (13)	−0.0117 (13)	−0.0251 (10)
C19	0.116 (2)	0.0745 (16)	0.0709 (16)	0.0229 (16)	0.0094 (16)	−0.0093 (12)
C20	0.0769 (16)	0.0944 (18)	0.0676 (15)	0.0116 (15)	0.0276 (14)	−0.0005 (13)
C21	0.0621 (15)	0.111 (2)	0.0934 (19)	0.0084 (16)	0.0258 (15)	−0.0032 (16)
C22	0.191 (4)	0.117 (2)	0.120 (3)	0.072 (3)	−0.003 (3)	−0.029 (2)
C23	0.0886 (17)	0.0782 (16)	0.0418 (11)	0.0033 (14)	0.0077 (12)	0.0046 (10)
O24	0.1015 (13)	0.1035 (13)	0.0679 (10)	0.0172 (12)	−0.0157 (9)	−0.0089 (9)
O25	0.1331 (17)	0.0745 (10)	0.0759 (12)	0.0125 (12)	−0.0110 (11)	−0.0040 (9)
C26	0.102 (2)	0.122 (2)	0.094 (2)	0.027 (2)	−0.0055 (17)	0.0224 (17)

Geometric parameters (Å, º) top

N1—C2	1.382 (3)	C14—H14A	0.9700
N1—C13	1.381 (2)	C14—H14B	0.9700
N1—H1	0.8600	C15—C16	1.502 (3)
C2—C7	1.356 (3)	C15—C20	1.524 (3)
C2—C3	1.492 (3)	C15—H15	0.96 (2)
C3—N4	1.470 (3)	C16—C17	1.333 (3)
C3—C14	1.521 (3)	C16—C23	1.454 (3)
C3—H3	0.98 (2)	C17—O18	1.334 (3)
N4—C21	1.466 (3)	C17—H17	0.9300
N4—C5	1.475 (3)	O18—C19	1.461 (3)
C5—C6	1.508 (3)	O18—O24ⁱ	3.199 (2)
C5—H5A	0.9700	C19—C22	1.515 (4)
C5—H5B	0.9700	C19—C20	1.517 (4)
C6—C7	1.497 (3)	C19—H19	0.9800
C6—H6A	0.9700	C20—C21	1.522 (4)
C6—H6B	0.9700	C20—H20	1.03 (3)
C7—C8	1.427 (3)	C21—H21A	0.9700
C8—C9	1.400 (3)	C21—H21B	0.9700
C8—C13	1.412 (3)	C22—H22A	0.9600
C9—C10	1.372 (4)	C22—H22B	0.9600
C9—H9	0.9300	C22—H22C	0.9600
C10—C11	1.392 (4)	C23—O25	1.205 (3)
C10—H10	0.9300	C23—O24	1.340 (3)
C11—C12	1.374 (3)	O24—C26	1.430 (3)
C11—H11	0.9300	C26—H26A	0.9600
C12—C13	1.381 (3)	C26—H26B	0.9600
C12—H12	0.9300	C26—H26C	0.9600
C14—C15	1.533 (3)

C2—N1—C13	108.68 (16)	C15—C14—H14B	109.4
C2—N1—H1	125.7	H14A—C14—H14B	108.0
C13—N1—H1	125.7	C16—C15—C20	109.01 (19)
C7—C2—N1	109.74 (19)	C16—C15—C14	113.25 (19)
C7—C2—C3	125.07 (18)	C20—C15—C14	111.00 (19)
N1—C2—C3	125.14 (17)	C16—C15—H15	109.3 (14)
N4—C3—C2	107.76 (17)	C20—C15—H15	108.5 (14)
N4—C3—C14	109.48 (16)	C14—C15—H15	105.7 (14)
C2—C3—C14	113.41 (16)	C17—C16—C23	120.7 (2)
N4—C3—H3	111.4 (13)	C17—C16—C15	120.5 (2)
C2—C3—H3	107.9 (13)	C23—C16—C15	118.75 (19)
C14—C3—H3	106.9 (13)	C16—C17—O18	126.3 (3)
C21—N4—C3	109.28 (18)	C16—C17—H17	116.8
C21—N4—C5	110.49 (19)	O18—C17—H17	116.8
C3—N4—C5	111.60 (17)	C17—O18—C19	116.12 (18)
N4—C5—C6	111.05 (18)	C17—O18—O24ⁱ	117.37 (15)
N4—C5—H5A	109.4	C19—O18—O24ⁱ	120.05 (15)
C6—C5—H5A	109.4	O18—C19—C22	105.0 (2)
N4—C5—H5B	109.4	O18—C19—C20	109.0 (2)
C6—C5—H5B	109.4	C22—C19—C20	116.0 (3)
H5A—C5—H5B	108.0	O18—C19—H19	108.9
C7—C6—C5	109.63 (18)	C22—C19—H19	108.9
C7—C6—H6A	109.7	C20—C19—H19	108.9
C5—C6—H6A	109.7	C19—C20—C21	114.0 (2)
C7—C6—H6B	109.7	C19—C20—C15	109.4 (2)
C5—C6—H6B	109.7	C21—C20—C15	110.4 (2)
H6A—C6—H6B	108.2	C19—C20—H20	108.9 (14)
C2—C7—C8	107.32 (17)	C21—C20—H20	104.1 (14)
C2—C7—C6	121.7 (2)	C15—C20—H20	109.9 (14)
C8—C7—C6	130.99 (19)	N4—C21—C20	111.5 (2)
C9—C8—C13	118.4 (2)	N4—C21—H21A	109.3
C9—C8—C7	134.6 (2)	C20—C21—H21A	109.3
C13—C8—C7	107.01 (17)	N4—C21—H21B	109.3
C10—C9—C8	119.3 (2)	C20—C21—H21B	109.3
C10—C9—H9	120.3	H21A—C21—H21B	108.0
C8—C9—H9	120.3	C19—C22—H22A	109.5
C9—C10—C11	120.9 (2)	C19—C22—H22B	109.5
C9—C10—H10	119.5	H22A—C22—H22B	109.5
C11—C10—H10	119.5	C19—C22—H22C	109.5
C12—C11—C10	121.3 (2)	H22A—C22—H22C	109.5
C12—C11—H11	119.3	H22B—C22—H22C	109.5
C10—C11—H11	119.3	O25—C23—O24	122.2 (2)
C11—C12—C13	117.8 (2)	O25—C23—C16	124.4 (2)
C11—C12—H12	121.1	O24—C23—C16	113.4 (2)
C13—C12—H12	121.1	C23—O24—C26	117.4 (2)
C12—C13—N1	130.62 (19)	O24—C26—H26A	109.5
C12—C13—C8	122.13 (19)	O24—C26—H26B	109.5
N1—C13—C8	107.25 (18)	H26A—C26—H26B	109.5
C3—C14—C15	111.33 (17)	O24—C26—H26C	109.5
C3—C14—H14A	109.4	H26A—C26—H26C	109.5
C15—C14—H14A	109.4	H26B—C26—H26C	109.5
C3—C14—H14B	109.4

C13—N1—C2—C7	−0.7 (2)	C7—C8—C13—N1	−0.3 (2)
C13—N1—C2—C3	176.71 (18)	N4—C3—C14—C15	−57.9 (2)
C7—C2—C3—N4	17.0 (3)	C2—C3—C14—C15	−178.22 (18)
N1—C2—C3—N4	−159.97 (17)	C3—C14—C15—C16	174.62 (19)
C7—C2—C3—C14	138.4 (2)	C3—C14—C15—C20	51.6 (3)
N1—C2—C3—C14	−38.6 (3)	C20—C15—C16—C17	17.6 (3)
C2—C3—N4—C21	−173.13 (18)	C14—C15—C16—C17	−106.5 (3)
C14—C3—N4—C21	63.1 (2)	C20—C15—C16—C23	−159.33 (19)
C2—C3—N4—C5	−50.6 (2)	C14—C15—C16—C23	76.6 (3)
C14—C3—N4—C5	−174.38 (18)	C23—C16—C17—O18	−179.2 (2)
C21—N4—C5—C6	−169.4 (2)	C15—C16—C17—O18	4.0 (4)
C3—N4—C5—C6	68.8 (2)	C16—C17—O18—C19	8.7 (4)
N4—C5—C6—C7	−45.6 (2)	C16—C17—O18—O24ⁱ	−143.1 (2)
N1—C2—C7—C8	0.5 (2)	C17—O18—C19—C22	−166.5 (3)
C3—C2—C7—C8	−176.90 (18)	O24ⁱ—O18—C19—C22	−15.5 (3)
N1—C2—C7—C6	178.97 (16)	C17—O18—C19—C20	−41.6 (3)
C3—C2—C7—C6	1.6 (3)	O24ⁱ—O18—C19—C20	109.46 (19)
C5—C6—C7—C2	12.5 (3)	O18—C19—C20—C21	−173.59 (19)
C5—C6—C7—C8	−169.4 (2)	C22—C19—C20—C21	−55.4 (3)
C2—C7—C8—C9	−179.6 (2)	O18—C19—C20—C15	62.3 (3)
C6—C7—C8—C9	2.1 (4)	C22—C19—C20—C15	−179.5 (2)
C2—C7—C8—C13	−0.1 (2)	C16—C15—C20—C19	−49.3 (3)
C6—C7—C8—C13	−178.41 (19)	C14—C15—C20—C19	76.1 (3)
C13—C8—C9—C10	1.8 (3)	C16—C15—C20—C21	−175.5 (2)
C7—C8—C9—C10	−178.8 (2)	C14—C15—C20—C21	−50.1 (3)
C8—C9—C10—C11	−0.7 (3)	C3—N4—C21—C20	−63.3 (3)
C9—C10—C11—C12	−1.1 (4)	C5—N4—C21—C20	173.5 (2)
C10—C11—C12—C13	1.8 (3)	C19—C20—C21—N4	−67.0 (3)
C11—C12—C13—N1	178.8 (2)	C15—C20—C21—N4	56.6 (3)
C11—C12—C13—C8	−0.7 (3)	C17—C16—C23—O25	−176.4 (3)
C2—N1—C13—C12	−179.0 (2)	C15—C16—C23—O25	0.5 (3)
C2—N1—C13—C8	0.6 (2)	C17—C16—C23—O24	2.8 (3)
C9—C8—C13—C12	−1.0 (3)	C15—C16—C23—O24	179.7 (2)
C7—C8—C13—C12	179.33 (19)	O25—C23—O24—C26	1.0 (4)
C9—C8—C13—N1	179.34 (18)	C16—C23—O24—C26	−178.2 (2)

Symmetry code: (i) x+1/2, −y+3/2, −z.

Hydrogen-bond geometry (Å, º) top

Cg1 and Cg2 are the centroids of the C8–C13 and C2/C7/C8/C13/N1 rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···Cg1ⁱⁱ	0.86	2.85	3.550 (2)	139
C6—H6A···Cg2ⁱⁱⁱ	0.97	2.8	3.429 (3)	121

Symmetry codes: (ii) −x, y+1/2, −z+1/2; (iii) −x+1, y−1/2, −z+1/2.

Hydrogen-bond geometry (Å, º) top

Cg1 and Cg2 are the centroids of the C8–C13 and C2/C7/C8/C13/N1 rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···Cg1ⁱ	0.86	2.85	3.550 (2)	139
C6—H6A···Cg2ⁱⁱ	0.97	2.8	3.429 (3)	121

Symmetry codes: (i) −x, y+1/2, −z+1/2; (ii) −x+1, y−1/2, −z+1/2.

Acknowledgements

The authors thank Université Paris Descartes and the CNRS for financial support.

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Volume 69| Part 9| September 2013| Pages o1389-o1390

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