Structure elucidation of a dihydropyranone from Tapinanthus dodoneifolius

Article abstract of DOI:10.1021/np070355x

A new dihydropyranone, (R)-6-[(S)-2-hydroxy-4-(4-hydroxyphenyl)butyl]-5,6- dihydropyran-2-one (1), was isolated from Tapinanthus dodoneifolius. The structure was determined from spectroscopic and X-ray crystallographic analysis. Compound 1 (named dodonein

Full text of DOI:10.1021/np070355x

2006
J. Nat. Prod. 2007, 70, 2006–2009
Structure Elucidation of a Dihydropyranone from Tapinanthus dodoneifolius
Maurice Ouedraogo,† Hélène Carreyre,‡ Clarisse Vandebrouck,† Jocelyn Bescond,† Guy Raymond,† Innocent-Pierre Guissou,§
Christian Cognard,† Frédéric Becq,† Daniel Potreau,† Alain Cousson, Jérôme Marrot,O and Jean-Marie Coustard*,‡
Institut de Physiologie et Biologie Cellulaires, UniVersité de Poitiers, CNRS/UMR 6187, 40 AVenue du Recteur Pineau, F-86022 Poitiers
Cedex, France, Laboratoire de Synthèse et RéactiVité des Substances Naturelles, UniVersité de Poitiers, UMR CNRS 6514, 40 AVenue du
Recteur Pineau, F-86022 Poitiers Cedex, France, Institut de Recherche en Sciences de la Santé (IRSS/CNRST), BP 7192, Ouagadougou,
Burkina Faso, Laboratoire Léon Brillouin, CEA Saclay, Bâtiment 563, F-91191 Gif sur YVette Cedex, France, and Institut LaVoisier,
UMR CNRS 8180, UniVersité de Versailles, St Quentin en YVelines, 45 AVenue des Etats-Unis, F-78035 Versailles Cedex, France
ReceiVed July 21, 2007
A new dihydropyranone, (R)-6-[(S)-2-hydroxy-4-(4-hydroxyphenyl)butyl]-5,6-dihydropyran-2-one (1), was isolated from
Tapinanthus dodoneifolius. The structure was determined from spectroscopic and X-ray crystallographic analysis.
Compound 1 (named dodoneine) showed a relaxing effect on preconstricted rat aortic rings (IC50 of 81.4 ( 0.9 µM).
Tapinanthus dodoneifolius (DC) Dancer (Lorenthaceae), known
as African mistletoe, is a hemiplant parasite widely spread in the
Sahelian region. T. dodoneifolius is used as a remedy to treat
wounds, stomachache, diarrhea, cholera, nervous confusion, and
cardiovascular and respiratory diseases. Chemical screening indi-
cated the presence of tannins, anthracenosides, anthraquinones,
alkaloids, saponins, sterols, and triterpenes in the plant.1–4
phenolic ring is bearing a -CH2-CH2- group, a methylene group is
between two >CH-O-, and the R,ꢀ-unsaturated lactone ring is
substituted at the 6 position. The 1H and 13C NMR data of this 6-alkyl-
substituted-5,6-dihydro-2H-pyran-2-one moiety were very similar to
values reported elsewhere for compounds having comparable structural
features.5–7 Compound 1 exists as a sole dextrorotatory enantiomer,
as indicated by polarimetric analysis and chiral liquid chromatography.
The sample of T. dodoneifolius DC Danser used in this study
was collected in June 2005 on a sheanut tree (Vitellaria paradoxa
CF Gaertn (Sapotaceae)), in Loumbila, 20 km northeast from
Ouagadougou, Burkina Faso (West Africa).
The dried and ground whole plant was extracted using an
accelerated solvent extractor apparatus (ASE, Dionex) operating
at 60 °C and under pressure. The physiological activity of the
methanolic extract was close to the effects observed from the
conventional extract of the whole plant. A TLC analysis of its
methanolic extract indicated the presence of the main compound
1, a viscous oil that slowly crystallized with one molecule of water
to afford colorless prisms that were further purified by crystallization
from petroleum ether/toluene: melting point 57–58 °C (uncorrected),
The relative configuration of both asymmetric carbons was estab-
lished as follows: reduction of 1 in methanol, with hydrogen over Pd/
C, led to the 1,3-diol methyl ester 2 (Scheme 1). This compound
reacted with 2,2-dimethoxypropane, under acidic catalysis, to afford
the isopropylydene derivative 3. In the 13C NMR spectrum, the
isopropylydene methyl groups resonated as separate signals at δC 19.87
and 30.25, consistent with a syn-1,3-diol configuration in the starting
compound 2 (Scheme 1). Otherwise, an anti-1,3-diol configuration
should have given two signals close to 25 ppm.8
[R]25 +40.2 (c 0.4, CHCl3, >99% ee). FT-IR analysis revealed
D
the presence of conjugated carbonyl (1698 cm-1) and OH (3351
cm-1) groups. UV absorption at λmax 275 nm indicated the presence
of an R,ꢀ-unsaturated δ-lactone moiety. The molecular weight was
estimated from an ESIMS experiment (M + Na+ 285 and M2 +
Na+ 547), and the molecular formula C15H18O4, with seven degrees
of unsaturation, was deduced from HRESIMS of the pseudomo-
1
lecular ion (M + Na)+. H NMR analysis in CDCl3 revealed the
In the biphasic system water/CH2Cl2 containing K2CO3, 1 underwent
an easy intramolecular cyclization by conjugate addition of the
hydroxyl group to the double bond, to afford the thermodynamically
stable bicyclic lactone 4.9 The spectroscopic properties of 4 agreed
with values reported elsewhere for related systems.9,10 Treatment of
4 with (1S)-(+)-10-camphorsulfonyl chloride afforded the correspond-
ing optically active camphorsulfonate 5. X-ray crystallographic
analysis, because of the known configuration of the camphorsulfonate
moieties, allowed the absolute configuration determination of every
asymmetric carbon in 5 (Scheme 1).11–13 The configurations of the
C-1 and C-7 carbons in the bicyclic compound 4 are identical to the
corresponding carbons in 1 (Scheme 1). These observations are in
agreement with the structure of the syn-1,3-diol methyl ester 2 and
also imply that no inversion of configuration had occurred during the
reduction of 1 with H2 over Pd/C (Figure 1). Thus, it was concluded
that 1 is (R)-6-[(S)-2-hydroxy-4-(4-hydroxyphenyl)butyl]-5,6-dihydro-
pyran-2-one, named dodoneine.
presence of a para-substituted phenyl ring, with signals at δ 6.98
and 6.69, two coupled vinylic protons at δ 6.82 and 5.95 (R,ꢀ-
conjugated lactone) on a cis-double-bond (J ≈ 9.6 Hz), two exchange-
able protons at δ 1.59 and 2.17 (broad signals, OH), and seven aliphatic
protons appearing as multiplets ranging from δ 4.57 to 1.72. The 13
C
NMR data showed 13 signals including a carbonyl resonance at δ
164.7, six aromatic or vinylic signals from δ 154.6 to 115.8, and six
aliphatic carbon signals ranging from δ 77.5 to 29.9. A DEPT 135
experiment revealed the presence of four CH2 and six CH groups (2
1
× two aromatic, two vinylic, and two >CH-O-). H-1H COSY,
HMBC, and HMQC experiments indicated that the para-substituted
* To whom correspondence should be directed. Tel: +33 (0)54 945 4100.
Fax: +33 (0)54 945 3501. E-mail: jean.marie.coustard@univ-poitiers.fr.
† Institut de Physiologie et Biologie Cellulaires, Université de Poitiers.
‡ Laboratoire de Synthèse et Réactivité des Substances Naturelles,
Université de Poitiers.
§ Institut de Recherche en Sciences de la Santé, Ouagadougou.
Laboratoire Léon Brillouin, Saclay.
Experiments using dodoneine (1) were performed on rat aortic
rings mounted in an organ bath apparatus to study the vasodilator
O Institut Lavoisier, Versailles.
10.1021/np070355x CCC: $37.00
2007 American Chemical Society and American Society of Pharmacognosy
Published on Web 12/06/2007

Notes
Journal of Natural Products, 2007, Vol. 70, No. 12 2007
Scheme 1. Dodoneine (1) Chemical Transformationsa
Figure 2. Vasorelaxant effect of dodoneine (1) on rat aorta.
Concentration-dependent curve is displayed, showing the vasore-
laxation effect on the aortic rings preconstricted with 1 µM
norepinephrine.
ceae)) near the town of Loumbila, 20 km northeast of Ouagadougou,
Burkina Faso (West Africa), in June 2005. A voucher specimen was
deposited in the Herbarium of the Department of Vegetal Biology,
University of Ouagadougou, Burkina Faso, with the reference no. 002.
Extraction and Isolation. The air-dried and ground whole plant
of T. dodoneifolius (49.7 g) was packed in the column of the accelerated
solvent extractor apparatus (ASE, Dionex). The extraction temperature
was set to 60 °C with a flow rate of 10 mL/min. The column was first
percolated with petroleum ether (3 × 100 mL), then with CH2Cl2 (3 ×
100 mL), methanol (3 × 100 mL), and finally water (100 mL). The
solvents were eliminated under reduced pressure, to afford 1.6, 1.2,
10.1, and 3.3 g of extracted material as viscous, colored oils or solid
(water), respectively.
a (a) H2-Pd/C(10%) in methanol, (b) 2,2-dimethoxypropane in anhydrous
acetone, para-toluenesulfonic acid as catalyst, ∆, (c) K2CO3 as catalyst, in the
biphasic system water/CH2Cl2, (d) (1S)-(+)-10-camphorsulfonyl chloride in
pyridine, DMAP as catalyst.
The methanolic extract (3.00 g) was chromatographed on silica gel,
using CH2Cl2/EtOH (0 to 5% EtOH) to afford compound 1 (0.90 g,
3.0%) as a colorless, very viscous oil that slowly crystallized.
(R)-6-[(S)-2-Hydroxy-4-(4-hydroxyphenyl)butyl]-5,6-dihydropy-
ran-2-one (1): colorless crystals C15H18O4 ·H2O (petroleum ether/
toluene); mp 57–58 °C; [R]25D +40.2 (c 0.40 CHCl3); UV (EtOH) λmax
(log ꢀ) 227 (2.59), 275 (1.86) nm; IR (KBr) νmax 3351, 2920, 1698,
1
1514 cm-1; H NMR (CDCl3, 500 MHz) δH 6.98 (d, J ) 8.5 Hz, 2H,
H-2′), 6.88 (dt, J ) 9.7, 4.3 Hz, 1H, H-4), 6.69 (dt, J ) 8.5, 2.5 Hz,
2H, H-3′′), 6.02 (dt, J ) 10.4, 1.5 Hz, 1H, H-3), 4.64 (dddd, J ) 7.7,
7.7, 7.7, 5.4 Hz, 1H, H-6), 3.80 (br multiplet, 1H, H-2′), 2.60 (m, 2H,
H-4′), 2.38 (m, 2H, H-5), 2.00 (dt, J ) 14.7, 8.2 Hz, 1H, H-1′), 2.15
(br s, 1H, OH), 1.78 (m, 1H, H-1′), 1.72 (m, 2H, H-3′), 1.5 (br s, 1H,
OH); 13C NMR (CDCl3, 75 MHz) δC 164.7 (qC, C-2), 154.6 (qC, C-4″),
145.9 (CH, C-4), 133.9 (qC, C-1′′), 129.8 (2 × CH, C-2′′), 121.6 (CH,
C-3), 115.7 (2 × CH, C-3′′), 77.5 (CH, C6), 69.0 (CH, C-2′), 42.4
(CH2, C-1′), 39.7 (CH2, C-3′), 31.2 (CH2, C-4′), 29.9 (CH2, C-5);
ESIMS m/z 285 (M + Na)+; HRESIMS m/z 285.1094 (calcd for
C15H18O4Na, 285.1103).
Figure 1. X-ray crystal structure of camphorsulfonate 5 showing
the stereogenic centers.
activity.14,15 Dodoneine (1) relaxed preconstricted aortic rings with
half-maximal relaxation IC50 value of 81.4 ( 0.9 µM (n ) 4)
(Figure 2).
Experimental Section
The enantiomeric excess was determined by chiral stationary-phase
HPLC analysis (Daicel Chiralcel OD-H (4.5 mm × 25 cm) column
with eluent i-PrOH/hexane 40/60, flow rate 0.8 mL ·min-1, tR 8.41 min).
(5R,7S)-5,7-Dihydroxy-9-(4-methoxyphenyl)nonanoic acid methyl
ester (2). Compound 1 (52 mg, 0.20 mmol) in MeOH (4 mL) under
stirring was treated with Pd/C 10% (25 mg) under H2 for 2 h. After
filtration through sintered glass and washing of the filter with CH2Cl2
(2 × 2 mL), the organic phases were reassembled, then evaporated
under vacuum. A short column chromatography (Polar phase cyano-
General Experimental Procedures. Melting points were deter-
mined on a Büchi melting point B-545 apparatus and are uncorrected.
Optical rotations were measured at room temperature on a Schmidt
Polatronic HH8 polarimeter. UV spectra were recorded on a Genesys
Thermo Spectronic 10UV spectrophotometer. IR spectra were recorded
on a Nicolet Magna 750 FTIR as a KBr pellet. NMR spectra were
recorded on a Bruker Advance DPX300 spectrometer (1H at 300 MHz
and 13C at 75 MHz) or a Bruker Advance DPX500 spectrometer (1H at
500 MHz and 13C at 125 MHz), in CDCl3 solution at 25 °C, and the
solvent signal was used as a secondary reference for 13C NMR analysis.
Analytical HPLC was performed on a Waters 2487 chromatograph
equipped with a UV dual detector (measured at 227 and 275 nm).
Preparative extraction was realized on an ASE 100 Dionex apparatus.
Plant Material. Tapinanthus dodoneifolius (DC.) Danser was
collected on a sheanut tree (Vitellaria paradoxa CF Gaertn (Sapota-
propylsilane bonded to silica gel 40 µm, 60 Å/CH2Cl2) afforded 2 (56
1
mg, 95%) as a colorless oil: [R]25 -10.8 (c 0.88, CHCl3); H NMR
D
(CDCl3, 300 MHz) δH 7.30 (br s, 1H, OH phenol). 6.98 (d, J ) 8.5
Hz, 2H ar), 6.74 (d, J ) 8.5 Hz, 2H, arH), 4.11 (br s, 2 × OH alcohol),
3.84 (br s, 2 × >CH-O), 3.65 (s, 3H, OCH3 ester), 2.54 (m, 2H,
benzylic CH2), 2.32 (t, J ) 7.3 Hz, 2H, CH2), 1.68 (m, 4H), 1.56 (m,

2008 Journal of Natural Products, 2007, Vol. 70, No. 12
Notes
2H), 1.47 (m, 2H); 13C NMR (CDCl3, 75 MHz) δC 174.7 (CdO ester),
154.2 (ipso C-OH), 133.3 (ipso C-alkyl), 129.5 (2 × arC), 115.3 (2 ×
arC), 72.31 (>CH-O), 72.23 (>CH-O), 51.7 (OCH3 ester), 42.5 (CH2,
C-6), 39.7 (CH2), 37.2 (CH2), 35.7 (CH2), 33.8 (CH2), 30.7 (CH2), 20.5
(CH2, C-3); ESIMS m/z 319 (M + Na)+; HRESIMS m/z 319.1514
(calcd for C16H24O5Na+, 319.1521).
APEX2 CCD area-detector diffractometer using Mo KR radiation (λ
) 0.71073 Å). Six sets of narrow data frames (60 s per frame) were
collected at different values of θ for one and five initial values of ꢁ
and ω using 0.5° increments of ꢁ or ω, respectively. Data reductions
were accomplished using SAINT V7.03.11 The substantial redundancy
(3.84) in data allowed a semiempirical absorption correction (SADABS
V2.10)11 to be applied, on the basis of multiple measurements of
equivalent reflections. The structures were solved by direct methods,
developed by successive difference Fourier syntheses, and refined by
full-matrix least-squares on all F2 data using SHELXTL V6.14.12
Hydrogen atoms were included in calculated positions and allowed
to ride on their parent atoms. Crystal data: C25H32O7S, Mw ) 476.57,
monoclinic, space group P21; dimensions: a ) 8.700(4) Å, b )
10.245(5) Å, c ) 13.949(7) Å, ꢀ ) 100.21(2)°, V ) 1223.5(10) Å3; Z
) 2; Dc ) 1.294 g cm-3; µ ) 0.174 mm-1; total reflections collected:
12 246; independent reflections: 4296 (2613Fo > 4σ(Fo)); data were
collected up to a 2θmax value of 50° (99.9% coverage), F(000) ) 508,
number of variables: 300; R1 ) 0.0732, wR2 ) 0.2069, GOF ) 0.984;
max./min., absolute structure parameter -0.04(14), residual electron
4-{(4S,6R)-6-[2-(4-Hydroxyphenyl)ethyl]-2,2-dimethyl-[1,3]dioxin-
4-yl}butyric acid methyl ester (3). To a stirred solution of 2 (27.5
mg, 0.093 mmol) in anhydrous acetone (4 mL) were added
(MeO)2CMe2 (21 mg, 0.202 mmol) and p-TsOH (4 mg). After refluxing
under nitrogen for 3 h, the solvent was eliminated under vacuum. The
residue was dissolved in CH2Cl2 (3 mL), neutralized with 2 drops of
Na2CO3 saturated solution, then dried with anhydrous MgSO4. The
organic phase was removed and the solid residue further extracted with
CH2Cl2 (3 mL). The organic phases were reassembled, then concentrated
under vacuum. A short column chromatography (Polar phase cyano-
propylsilane bonded to silica gel 40 µm, 60 Å/hexane/CH2Cl2, 3:1)
afforded 3 (26 mg, 83%) as a colorless oil: [R]25 -10.5 (c 0.80,
D
CHCl3); 1H NMR (CDCl3, 300 MHz) δH 7.03 (dt, J ) 8.2, 2.3 Hz, 2H,
meta-phenol), 6.75 (dt, J ) 8.2, 2.3 Hz, 2H, ortho-phenol), 5.29 (br s,
1H, --OH), 3.76 (m, 2H, 2 × >CH-O), 3.66 (s, 3H, OCH3 ester),
2.60 (m, 2H, CH2), 2.31 (t, J ) 7.6 Hz, CH2), 1.6–2.8 (m, 4H), 1.4–1.6
(m, 2H), 1.401 (s, 3H, isopropylydene CH3), 1.396 (s, 3H, isopropy-
lydene CH3), 1.25 (m, 2H). 13C NMR (CDCl3, 75 MHz) δC 174.2 (CdO
ester), 153.7 (ipso C-phenol), 134.0 (ipso C-alkyl), 129.6 (2 × CH
meta-phenol), 115.1 (2 × CH ortho-phenol), 98.6 (isopropylydene qC),
68.6 (>CH-O), 67.8 (>CH-O), 51.5 (ester OMe), 38.1 CH2 (ꢀ-ar CH2),
36.9 (dioxane CH2), 35.7 (γ-ester CH2), 33.8 (R-ester CH2), 30.2 (CH3
isopropylydene), 30.2 (benzylic CH2), 20.6 (ꢀ-ester CH2), 19.9 (CH3
isopropylydene); ESIMS m/z 359 (M + Na)+; HRESIMS m/z 359.1840
(calcd for C19H28O5Na+, 359.1834).
density 0.434 /-0.230 e Å-3
.
Contraction Measurement on Isolated Aortic Rings. All experi-
ments were performed on male Wistar rats (250-300 g).14,15 The
thoracic aorta of animals killed by cervical dislocation was removed
and placed into Krebs solution containing 120 mM NaCl, 4.7 mM KCl,
2.5 mM CaCl2, 1.2 mM MgCl2, 15 mM NaHCO3, 1.2 mM KH2PO4,
11 mM D-glucose, and 10 mM Hepes, pH 7.4. After separation of
connective tissues, the thoracic segment of aorta was cut into rings of
3 mm in length. The preparation was then transferred into a 5 mL organ
bath containing Krebs solution bubbled with a mixture of 95% O2 and
5% CO2. Each aortic ring was suspended between two stainless steel
hooks. One of the hooks was mounted at the bottom of the bath, whereas
the other was connected to a IT1-25 force displacement transducer
(Emka Technologies). All experiments were performed at 37 °C. A
basal tension of 2 g was applied in all experiments. During 1 h, tissues
were rinsed three times in Krebs solution, and the basal tone was always
monitored and adjusted to 2 g. Norepinephrine (10-6 M) was used to
evoke the sustained contractile response. Once the sustained tension
was established, the tissues were allowed to equilibrate further for 30
min before cumulative addition of 1 to the bath. Cumulative concen-
tration–response relationship for the relaxant effect of dodoneine was
determined in aortic rings following stable contraction. The relaxant
effect was expressed as percentage contraction of the norepinephrine-
constricted arterial rings. IC50 is the drug concentration inducing a half-
maximal vasorelaxation effect (or inhibition of contraction). Data are
presented as mean ( SE of four experiments.
(1R,5S,7S)-[2-(4-Hydroxyphenyl)ethyl]-2,6-dioxabicyclo[3.3.1]-
nonan-3-one (4). To a stirred solution of dodoneine 1 (57 mg, 0.2
mmol) in CH2Cl2 (3.5 mL) were added K2CO3 (15 mg) and water (0.5
mL), and the mixture was stirred under N2 for 6 h. The organic phase
was separated and washed with brine (2 × 1 mL), dried over MgSO4,
and evaporated under vacuum to afford a white product, which was
further crystallized from acetonitrile (47 mg, 87%): mp 170–171 °C;
[R]25D -37.5 (c 0.44, CHCl3); 1H NMR (MeOH/CDCl3 300 MHz) δH
6.99 (dt, J ) 8.5, 2.4 Hz, 2H, meta-phenol), 6.71 (dt, J ) 8.5, 2.5 Hz,
2H, ortho-phenol), 4.87 (m, 1H, >CH-O), 4.34 (br s, 1H, >CH-O),
3.65 (m, 1H, >CH-O), 2.6 (cm, 4H), 1.98 (m, 3H), 1.92 (m, 1H), 1.7
(cm, 3H); 13C NMR (MeOH/CDCl3, 75 MHz) δC 172.4 (CdO lactone),
155.9 (ipso C-OH), 133.3 (ipso C-alkyl), 130.0 (2 × CH, meta-phenol),
115.9 (2 × CH, ortho-phenol), 74.7 (>CH-O), 66.8 (>CH-O), 65.5
(>CH-O), 38.6 (CH2), 37.6 (CH2), 36.8 (CH2), 31.1 (CH2), 30.1 (CH2);
ESIMS m/z 285 (M + Na)+; HRESIMS m/z 285.1093 (calcd for
C15H18O4Na+, 285.11028).
Acknowledgment. Thanks to CNRS-France and to the University
of Poitiers-France (“Programme d’Actions Incitatives”) for financial
support. Thanks also to “Agence Universitaire de la Francophonie”
for a research grant to one of us (M.O.). Special thanks to D. Lesur
(University of Picardie, France) and to L. Lemée (UMR 6514,
University of Poitiers, France).
((S)-7,7-Dimethyl-2-oxo-bicyclo[2.2.1]hept-1-yl)methanesulfonic acid
4-[2-((1R,3S,5S)-7-oxo-2,6-dioxabicyclo[3.3.1]non-3-yl)ethyl)phenyl es-
ter (5). To a solution of bicyclic lactone 4 (44 mg, 0.09 mmol) in
pyridine (1.5 mL) were added (1S)-(+)-10-camphorsulfonyl chloride
(205 mg, 0.8 mmol) and DMAP (5 mg) at RT. After 1 h reaction time,
CH2Cl2 (6 mL) was added, and the resulting solution was washed with
a 10% solution of NaHCO3 (3 × 5 mL). The organic phase was dried
with MgSO4 and evaporated under vacuum to afford a viscous oil.
Preparative thin-layer chromatography over silica gel (CH2Cl2/MeOH,
98:2) afforded camphorsulfonate 5 (50 mg, 68%), which was crystal-
lized from acetonitrile: mp 143–144 °C, [R]25D +12.7 (c 0.44, CHCl3);
1H NMR (CDCl3, 300 MHz) δH 7.21 (s, 4H, arH), 4.90 (br s, 1H, >CH-
O), 4.40 (br s, 1H, >CH-O), 3.77 (br s, 1H, >CH-O), 3.80 (d, J )
15.0 Hz, 1H), 3.19 (d, J ) 15.0 Hz, 1H), 2.80 (m, 3H), 2.5 (m, 3H),
References and Notes
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(11) APEX2 version 2.0–2; Bruker AXS: Madison, WI, 2003.
(12) SHELXTL version 6.14; Bruker AXS: Madison, WI, 2001.
2.0 (cm, 6H), 1.6 (cm, 5H), 1.15 (s, 3H, CH3), 0.91 (s, 3H, CH3); 13
C
NMR (CDCl3, 75 MHz) δC 214.1 (CdO ketone), 169.7 (CdO lactone),
147.4 (ipso C-OH), 140.8 (ipso C-alkyl), 129.7 (2 × CH, meta-phenol),
122.0 (2 × CH ortho-phenol), 73.0 (>CH-O), 65.9 (>CH-O), 65.0
(>CH-O), 58.1 (qC), 47.9 (qC), 47.4, 42.8 (CH), 42.4 (CH2), 37.5
(CH2), 36.9 (CH2), 36.4 (CH2), 31.0 (CH2), 29.7 (CH2), 26.8 (CH2),
25.1 (CH2), 19.9 (CH3), 19.7 (CH3).
X-ray Crystallographic Analysis of Compound 5.13 Suitable
single crystals for X-ray analyses were grown from a solution of
acetonitrile. A colorless crystal of dimensions 0.28 × 0.22 × 0.04 mm
was mounted with Araldite on a glass fiber. X-ray intensity data were
collected at room temperature, T ) 293(2) K, on a Bruker-Nonius X8-

Notes
Journal of Natural Products, 2007, Vol. 70, No. 12 2009
(13) Crystallographic data for compound 5 have been deposited with the
Cambridge Crystallographic Data Centre (deposit number CCDC
653149). Copies of the data can be obtained, free of charge, on
application to the Director, CCDC, 12 Union Road, Cambridge CB2
1EZ,UK(fax:+44-(0)1223-336033ore-mail:deposit@ccdc.cam.ac.uk),
or http//www.ccdc.cam.ac.uk.
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