Phy rochemisrry ,
Vol. 46, No. 4. pp. 745- 749,
1997
C 1997 Published by Elsevier Science Ltd. All rights resewed
Pergamon zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
Printed in Great Britain
@X-9422:97
PII: SOO31-9422(97)0019!&4
LIGNOIDS,
FLAVONOIDS
AND POLYKETIDES
%17.00+0.130
OF VIROLA zyxwvutsrqponmlkjih
SURINAMENSIS
EMA ESTER DE
zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
ALMEIDA BLUMENTHAL,* MARCELO SOBRALDA
zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQ
SILVA~ and MASSAYOSHI YOSHILIA~
Laboratorio de Quimica Organica, Instituto Butantan, C.P.65, C.E.P.01051, Sao Paulo-SP, Brazil; t Laboratorio de
Tecnologia Farmaceutica, Universidade Federal da Paraiba, C.P. 5009, C.E.P.58051-970, Joso Pessoa, Paraiba-PB, Brazil;
$ Instituto de Quimica-Universidade
de Sao Paulo, C.P. 26077, C.E.P.05599-970, SBo Paulo-SP, Brazil; Instituto de
Quimica, Universidade Estadual Paulista, C.P. 355, C.E.P. 14800-900, Araraquara, SPo Paulo-SP, Brazil
(Received
Key Word Index-Fir&
surinamensis;
10 December
Myristicaceae;
1996)
seeds; lignoids; llavonoids;
polyketides.
Abstract-From
the seeds of Virola surinamensis, which were collected near Altamira and near Maraba, Para
State, Brazil, the following substances were isolated by chromatographic
techniques: two dibenzylbutanediol
lignans, dihydrocubebin
and the new dihydrocubebin
monolaurate,
two furofuran lignans, sesamin and asarinin, three dibenzylbutyrolactol
lignans, cubebin, ,!?-O-methylcubebin
and a-U-methylcubebin,
one dibenzylbutyrolactone
lignan, hinokinin,
one aryltetralin
neolignan,
galbulin, two tetrahydrofuran
neolignans,
galgravin and the new 4’-hydroxy-3’-methoxy-3,4-methylenedioxy-S.8’,7.0.7’-neolignan,
one flavone, tithonine, one isoflavone, irisolidone, and two new polyketides, 3-hydroxy-l-(1 %phenylpentadecanoyl)-2,6-cyclohexanedione and I-(5-phenylpentanoyl)-2,6-cyclohexanedione.
Different chemical constitutions
of the fruits from
the two localities were observed. 0 1997 Published by Elsevier Science Ltd
INTRODUCTION
RESULTS AND DISCUSSION
Previous studies on Virolu species describe the occurHexane extracts of teguments and kernels from frurence of the lignans dihydrocubebin
(la) [l, 21, sesits of V. surinamensis collected near Altamira, Para
amin (2a) [l-5], asarinin (2b) zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
[l ,2, 61, cubebin (3b) [l,
State, Brazil, were submitted
to chromatographic
fractionation
affording
dihydrocubebin
(la) [ 111,
2,6], hinokinin (3e) [l, 2,3,6], the neolignans, galbulin
(4) [3] and galgravin (5a) 171,and the flavone tithonine
dihydrocubebin
monolaurate
(lb), sesamin (2a) [12,
131, asarinin (2b) [14], /3 and a-cubebin (3a and 3b)
(6) [2]. Leaves of V. surinamensis collected at Aura
[15, 161, hinokinin (3e) [17], galbulin (4) [18, 191, Hb
Forest Reserve, Beltm, Para State, Brazil, contain
and 8c. The chloroform
extract gave P-O-methylvirolin and surinamensin
which showed activity
cubebin (3~) [20] and a-0-methylcubebin
(3d) [2(1],
against penetration
of cercaria of Schistosoma manbesides la and 3e.
soni [S]. More
recently,
11 lignans,
three proChromatographic
fractionation
of the chloroform
piophenone
derivatives and two y-lactones were isoextract of kernels from fruits of V. surinamensis collated from leaves and seeds of V. surinamensis collected near Maraba, Para State, Brazil, afforded gallected at Combu Island, Para State, Brazil [9].
gravin (5a) [21, 221, 5c and tithonine (6) [23], besides
The chemical variability observed in specimens of
2a and 3b. The chloroform
extract from pericarps
V. surinamensis from different localities stimulated the
yielded irisolidone (7) [24].
analysis of fruits collected at Xingu river-bank (AltaThe lignans 3c, 3d and isoflavone 7 in Virolu and
mira-PA)
and Tocantins
river-bank
(Maraba-PA).
polyketides in V. surinamensis were isolated for the
These fruits contain two dibenzylbutanediol
lignans,
first time. Compounds 3c and 3d can be artifacts [20].
two furofuran lignans, three dibenzylbutyrolactol
ligThe lignan zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONM
lb, neolignan 5c and polyketides 8b and
nans, one dibenzylbutyrolactone
lignan, one aryl8c are unknown compounds.
tetralin neolignan, two tetrahydrofuran
neolignans,
The compounds
la, 2a-5a,
6 and 7, previously
one flavone, one isoflavone and two polyketides. The
isolated,
were
identified
by
comparison
with reported
nomenclature
and the numbering of lignans and neospectroscopic
data.
lignans follow the rules outlined in a review [lo].
Compound
lb showed many spectral
features in
common with dihydrocubebin
(la) zyxwvutsrqponmlkjihgfed
[l 11. The IR spectrum showed hydroxyl and carbonyl absorptions
at
3498 and 1733 cm-‘. The mass spectrum did not exhi*Author to whom correspondence should be addressed.
745
146
E. E. DEALMEIDA BLUMENTHAL~~
zyxwvutsrqponmlkjihgfedcbaZYXWVUTSR
al.
OH
Pi
la - R=H zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
2a - *a-Pi
1b - R=CO(CH2)&H3
2 b - tip-Pi
R2
Pi
Ve
4
3a-RI=
P-OH;Rz=H
3 b - RI = a-OH; R2=H
3c - Rl = P-OCH,; R2=H
3d - RI = a-OCH+ R2=H
38 _ Ri=R2=0
Ar
6
0
Sa - Rl=RLP-CHa;
Arl=Arka-Ve
Sb - R1=@CHa; R&-CH3;
Aha-Ve;
SC - Rf=P-CH3; RLa-CHg
Arl=a-Pi; A&@Gu
P
OH
A&p-Ve
0
0 zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
1’
1’
n
0
4
R
Sa - R=OH; n=10
8 b - R=OH; n=l4
SC - R=H; rrd
OH
0
Pi = 3,4-methybnedioxyphenyl
Ve =3,4dimethoxyphenyl
Gu 4hydroxy-3-methoxyphenyoxyphenyl
9
bit a [Ml+ at m/z 540. Elemental analysis, carbon
counts of the 13C NMR spectrum and proton integration of the ‘H NMR spectrum confirmed the linear
chain with 12 carbons. The mass spectrum shoaed
fragmentation
at m/z 340 corresponding
with
[M - CH3(CH2),,,COOH]+.
Constituents of zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLK
Virolasurinamensis
147
The ‘H NMR spectrum of 5c showed an all transgalbulin (4, 6 mg). Fr. C was submitted to flash CC
configuration of the tetrahydrofuran ring as in gal(silica gel, hexane-EtOAc, 7:3), followed by prep.
belgin (5b) [25]. These compounds differ only in the
TLC (silica gel, hexane-EtOAc, CHCl,-EtOAc) and
pattern of the aromatic rings: the veratryl groups of recrystallization from Me&X-hexane
giving dihy5b were replaced by piperonyl and guaiacyl groups in
drocubebin (la, 11 mg) and cubebin (3a and 3b, 123
5c. Compounds 5b and 5c showed the same [c$ value
mg).
and the structure (7S, 85, 7’S, 8’S)-4’-hydroxy-3’The CHCl, extract (7.4 g) was submitted to CC
methoxy-3,4-methylenedioxy-8.8’,7.0.7’-neolignan(silica gel, hexane-EtOAc, 9: 1, EtOAc) furnishing
A:1,3,5,1’,3’,5’ can be depicted for compound 5c.
initially frs D (223 mg) and E (4.4 g). Fr. D was
The IR absorptions and ‘H NMR spectra of comsubmitted to prep. TLC (silica gel, hexane-EtOAc),
pounds 8a [26] and Sb are closely comparable. The
followed by recrystallization from MeOH, yielding
mass spectrum of 8b exhibited a [M]+ at m/z 428 dihydrocubebin (la, 60 mg), /I-U-methylcubebin (3c,
supporting the presence of four additional methylene
23 mg) and a-0-methylcubebin
(3d, 25 mg). Fr. E
groups in the aliphatic chain. The structure of Se was
consisted essentially of a mixt. of la, 3c, 3d and 3e; it
established on the basis of ‘H and 13C NMR of the
was not fractionated.
cyclohexyl moiety of 9 [27] and the w-phenylacyl moiFrom seeds of fruits collected near Maraba, kernels
ety of 8a. The methylenic chain length was established
(300 g) and pericarps (200 g) were sepd, milled and
from the [Ml+ at m/z 272.
extracted with CHC13 at room temp. The CHCII
The lignan cubebin was isolated as a mixture of #l- extract (18 g) of kernels was crystallized from EtOH.
(3a) and ce(3b) anomers. We are including 13CNMR
Fatty material was filtered off and the mother liquo’
data for /I-cubebin whose ‘H NMR data were preconed under vacuum to yield 6 g. This residue was
viously described [ 151. zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
submitted to silica gel CC eluting with hexane and
hexane-EtOAc mixts of increasing polarity providing
frs F (2.2 g), G (1.8 g) and H (1.1 g). Part offr. F (220
EXPERIMENTAL
mg) was submitted to prep. TLC (silica gel, benzeneGeneral. Prep. TLC, flash CC and CC were carried
EtOAc) and recrystallization from hexane, affording
out on silica gel PF-254,60H and 60 (Merck), respecgalgravin (5a, 25 mg), cubebin (3b, 45 mg) and 5c (15’
tively. Mps are uncorr. ‘H NMR (200 MHz) and 13C mg). Part of fr. G (200 mg) was submitted to prep.
NMR (50 MHz) spectra were recorded in CDCl, with
TLC (silica gel, benzene_EtOAc) affording 5c (13 mg).
tithonine (6, 12 mg) and cubebin (3b, 65 mg). Fr. H
TMS as int. standard. EIMS were obtained at 70 eV.
was recrystallized from MeOH yielding sesamin (2a.
Plant material. Ripening fruits were collected near
350 mg).
Altamira and near Maraba, Para State, Brazil, by
The CHCl, extract (3.8 g) of pericarps was subDr Hipolito F. Paulino Filho (Universidade Estadual
mitted to recrystallization from EtOH and filtration
Paulista, Araraquara, SLo Paulo State, Brazil). The
of fatty material. The coned mother liquor (2.4 g) was
specimens were identified by Dr William A. Rodrigues
submitted to prep. TLC (silica gel, benzene_EtOAc),
(Instituto National
de Pesquisas da Amazonia,
followed by recrystallization from Me&O, affording
Manaus, Amazonas State, Brazil).
irisolidone (7, 14 mg).
Isolation of constituents. Seeds from both fruits were
(8R,8’R)- 9- Dodecanoy l- 9’- hy droxy - 3,4,3’,4’removed and air-dried. Teguments and kernels (200
dimethy lenedioxy - 8.8’~lignan- A: 1,3,5,1’,3’,5’ (lb). Oil.
g) from seeds collected near Altamira were milled
[alo- 13.3” (CHCl,; ~0.075). IR vE,“:cm-‘: 3498,2926,
and extracted in a Soxhlet apparatus successively with
2855,2776, 1733, 1609, 1490, 1443, 1362, 1247, 1189,
hexane and CHCI,. The hexane extract (11.3 g) was
1041, 930. ‘H NMR (200 MHz, CDC&): 6 0.85 (t,
suspended in hot MeOH and kept overnight at 0”.
J = 6.3 Hz, 3H-12”), 1.23 (br s, 2H-3” to 2H-1 l”),
The insoluble portion (0.9 g) was sepd by filtration,
1.88-1.97 (m, H-8, H-8’), 2.28 (t, J = 7.5 Hz; 2H-2”),
submitted to silica gel CC and elution with hexane2.53 (dd, J= 7.8, 13.8 Hz; 2H-7, 2H-7’), 2.70 (dd,
EtOAc mixts of increasing polarities; recrystallization
from Me,C&hexane
afforded polyketide 8b (0.4 g). J = 6.8, 13.8 Hz; 2H-7, 2H-7’) 3.59 (d, J = 5.4 Hz;
2H-9’), 4.01 (dd, J = 5.4, 11.3 Hz; 2H-9), 4.12 (dd,
The mother liquor was coned under vacuum and the
J= 6.0, 11.3Hz;2H-9),5.90(s,20CH,0),6.50-6.71
residue (8.5 g) partitioned between hexane and MeOH
(m, 6ArH). “C NMR (50 MHz, CDCl,): 6 13.7 (C(1: 9). The MeOH layer (2.5 g) was submitted to flash
12”), 22.3 (C-11”), 24.6 (C-3”) 28.9-29.3 (C-4” to CCC (silica gel, hexane-EtOAc, 4: 1) providing frs A
9”), 31.6 (C-lo”), 34.1 (C-2”), 35.1 (C-7), 35.3 (C-7’),
(173 mg), B (1.2 g) and C (466 mg). Fr. A was sub40.4 (C-8), 43.6 (C-8’), 62.6 (C-9’), 64.6 (C-9), 101.1
mitted to CC (silica gel, benzene), followed by prep.
(OCH,O), 108.4 (C-2, C-2’), 109.5 (C-5, C-5’), 122.1
TLC (silica gel, hexane-EtOAc) and finally recrys(C-6, C-6’), 145.8 (C-4, C-4’), 147.6 (C-3, C-3’), 173.7
tallization from Me&O-hexane giving sesamin (2a,
12 mg) asarinin (2b, 24 mg) and Sc (19 mg). Fr. B (C-l”). MS m/z (rel. int.): 340 (9) 135 (100). (Found:
C, 71.54; H, 8.33. C32H4407 requires: C, 71.11; H,
was submitted to CC (silica gel, hexaneCHC&, 1: l),
8.15%).
followed by prep. TLC (silica gel, benzene-MeOH,
(8R,8’R,9S)- 9- Hy droxy - 3,4,3’,4’- dimethy lenedioxy hexane-EtOAc,
CHCl,) yielding dihydrocubebin
8.8’,9.0.9’-lignand:
1,3,5,1’,3’,5’ (3a). 13C NMR (50
monolaurate (lb, 6 mg), hinokinin (3e, 815 mg) and
748
E. E.DEALMEDABLUMENTHAL~~
MHz, CDC&): S 33.5 (C-7), 38.8 (C-7’), 42.8 (C-8’),
51.9 (C-8), 72.4 (C-9’), 98.7 (C-9), 100.8 (OCH,O),
108.1 (C-2, C-2’), 109.1 (C-5,C-5’)
121.4(C-6’), 121.7
(C-6), 133.8 (C-l’), 134.5 (C-l), 145.7 (C-4, C-4’),
147.6 (C-3, C-3’).
zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQ
al.
(C-4), 24.2 (C-3’), 31.1 (C-4’), 33.2 (C-5), 35.7 (C-5’),
38.8 (C-3), 40.4 (C-2’), 113.0 (C-l), 125.7 (C-9’), 128.3
(C-7’, C-l l’), 128.4 (C-8’, C-lo’), 142.3 (C-6’), 195.3
(C-6), 198.6 (C-2), 206.1 (C-l’). MS m/z (rel. int.): 272
[Ml+ (l), 167 (63), 139 (lOO), 91 (48).
(8R,8’R,9S)- 9fi- M ethoxy - 3,4,3’,4’- dimethy tene-
dioxy-8.8’.9.0.9’-lignan-A:
1,3,5,1’,3’,5’ (Se). Amorphous solid. [alp-2.2”
(CHC&, c 0.2). i3C NMR (50
MHz, CDCl,): 6 33.6 (C-7), 39.3 (C-7’), 43.2 (C-8’),
52.1 (C-8), 54.5 (OCH& 72.2 (C-9’), 100.8 (OCH,O),
105.4 (C-9), 108.1 (C-2, C-2’), 108.9 (C-S’), 109.2 (C5), 121.4 (C-6’), 121.6 (C-6), 134.0 (C-l’), 134.8 (C-l),
145.6 (C-4’), 145.9 (C-4), 147.5 (C-3’), 147.7 (C-3).
(8R,8’R,9R)- 9a- M ethoxy - 3,4,3’,4’- dimethy lene-
dioxy-8.8’,9.0.9’-lignan-A:
1,3,5,1’,3’,5’ (3d). Oil.
[&-- 17.9“ (CHCl,; c 0.2). 13C NMR (50 MHz,
CDCl,): 6 38.7 (C-7’), 39.2 (C-7), 45.8 (C-8’), 52.4 (CS), 54.7 (OCH& 72.0 (C-9’), 100.8 (OCH,O), 108.0
(C-2, C-2’), 108.9 (C-5’), 109.1 (C-5), 109.9 (C-9),
121.4 (C-6’), 121.7 (C-6), 133.4 (C-l’), 134.2 (C-l),
145.7 (C-4’), 145.8 (C-4), 147.5 (C-3’), 147.6 (C-3).
(7S,8S,7’S,8’S)- 4’- Hy droxy - 3’- methoxy - 3,4-
methylenedioxy-8.8’,7.0.7’-neolignan-A:
1,3,5,1’,3’,5’
(5~). Oil. [ol]b- 17.9” (CHCl,; c 0.125) ‘H NMR (200
MHz, CDCl,): 6 1 .O (d, J = 5.8 Hz; 3H-9,3H-9’), 1.02
(d, J = 5.7 Hz; 3H-9, 3H-9’), 1.66-1.79 (m, H-8, H8’), 3.89 (s, OCH1), 4.59 (d, J = 9.2 Hz; H-7, H-7’),
5.56 (s, OH), 5.92 (s, OCH20), 6.73-7.01 (m, 6ArH).
13C NMR (50 MHz, CDC&): 6 13.8 (C-9, C-9’), 50.8
(C-8’), 51.1 (C-8), 55.9 (OCH,), 88.2 (C-7), 88.4 (C7’), 100.9 (OCH,O), 106.6 (C-2), 107.9 (C-5), 108.6
(C-2’), 114.0 (C-5’), 119.4 (C-6’), 119.7 (C-6), 134.1
(C-l’), 136.6 (C-l), 145.1 (C-4), 146.6 (C-3’), 146.9
(C-4), 147.8 (C-3). MS m/z (rel. int.): 342 [Ml+ (43),
192 (66) 190 (lOO), 180 (13), 178 (25), 177 (26), 175
(55) 164 (20), 162 (27), 152 (17), 151 (91) 150 (18),
149 (49).
3- Hy droxy 1-( 15- pheny lpentadecanoy l)- 2,6cy clohexanedione (8b). Colorless crystals. Mp 69-70”
(Me,CO-hexane).
[c(]n-5.0’ (CHC&; c 0.2). IR v:g
cm-‘: 3424,2919,2848,
1666, 1544, 1495, 1467, 1405,
1114, 755, 704. ‘H NMR (200 MHz, CDCl,): S 1.19
(br s, 9CH2), 1.54 (m, 3CH2), 1.62-1.85 (m, H-4,,),
2.24-2.37 (m, H-4,,), 2.53 (t, J= 7.7 Hz; 2H-15’),
2.68-2.76 (m, 2H-5), 2.80-3.08 (m, 2H-2’), 3.88 (s,
OH), 4.03 (dd, J = 4.4, 13.2 Hz; H-3), 7.04-7.24 (m,
5ArH). 13C NMR (50 MHz, CDC&): 6 24.5 (C-3’),
27.1 (C-5), 29.3-29.6 (C-4’to C-13’), 31.3 (C-4), 31.5
(C-14’), 36.0 (C-15’), 40.2 (C-2’), 71.6 (C-3), 110.3 (Cl), 125.5 (C-19’), 128.2 (C-17’, C-21’), 128.4 (C-18’,
C-20’), 142.9 (C-16’), 195.6 (C-6), 197.9 (C-2), 206.1
(C-l’). MS m/z (rel. int.): 428 [Ml+ (loo), 183 (19),
155 (3), 91 (33).
l- (5- Pheny lpentanoy f)- 2,6- cy clohexanedione
Acknowledgements- - W e
CAPES,
aid.
FAPESP
are grateful
and FEDIB
to CNPq,
for financial
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CDC&): 6 1.66-1.70 (m, 2H-3’, 2H-4’), 1.90-1.99 (m,
2H-4), 2.48 (t, J = 6.5 Hz; 2H-3, 2H-5’), 2.65 (t,
J = 6.2 Hz; 2H-5), 3.05 (t, J = 6.7 Hz; 2H-2’), 7.137.31 (m, SArH). “C NMR (50 MHz, CDCI,): 6 19.0
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Constituents zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIH
of Vii-ola surinamensis
749
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