Anthraquinones and lignans from Cassia occidentalis

Article abstract of DOI:10.1002/hlca.200900460

One new anthraquinone glycoside, 6-O-(α-L-rhamnopyranosyl-(1→6)- β-D-glucopyranosyl)emodin (1), and two new sesquilignans, seslignanoccidentaliols A (2) and B (3), were isolated from the whole plant of Cassia occidentalis. The structures of the new compounds were established by means of spectroscopic methods, especially 2D-NMR data (¹H, ¹H-COSY, HMQC, HMBC, and ROESY), as well as HR-ESI-MS analysis. One previously reported sesquilignan, erythro-guaiacylglycerol-β-O-4′- (5′)-methoxylariciresinol, was revised to be seslignanoccidentaliol A (2). The 6-O-(α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranosyl)emodin (1) exhibited moderate anti-HIV-1 activity with an EC₅₀ value of 2.90 μg/ml and a therapeutic-index (TI) value of 260.

Full text of DOI:10.1002/hlca.200900460

Helvetica Chimica Acta – Vol. 93 (2010)
1795
Anthraquinones and Lignans from Cassia occidentalis
a
b
a
a
a
a
a
b
by Shi-Fei Li ) ), Ying-Tong Di ), Yue-Hu Wang ), Cheng-Jian Tan ), Xin Fang ), Yu Zhang ) ),
c
d
a
a
a
Yong-Tang Zheng ), Ling Li ), Hong-Ping He ), Shun-Lin Li* ), and Xiao-Jiang Hao* )
a) State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of
Botany, Chinese Academy of Sciences, Kunming 650204, P. R. China
(
phone: þ 86-871-5223263; e-mail: lisl@mail.kib.ac.cn, haoxj@mail.kib.ac.cn)
b) Graduate School of Chinese Academy of Sciences, Beijing 100049, P. R. China
c) Laboratory of Molecular Immunopharmacology, Kunming Institute of Zoology, Chinese Academy of
Sciences, Kunming 650223, P. R. China
d) Yunnan Pharmacological Laboratories of Natural Products, Kunming Medical College, Kunming
6
50031, P. R. China
One new anthraquinone glycoside, 6-O-(a-l-rhamnopyranosyl-(1 ! 6)-b-d-glucopyranosyl)emodin
1), and two new sesquilignans, seslignanoccidentaliols A (2) and B (3), were isolated from the whole
(
plant of Cassia occidentalis. The structures of the new compounds were established by means of
1
1
spectroscopic methods, especially 2D-NMR data ( H, H-COSY, HMQC, HMBC, and ROESY), as well
as HR-ESI-MS analysis. One previously reported sesquilignan, erythro-guaiacylglycerol-b-O-4’-(5’)-
methoxylariciresinol, was revised to be seslignanoccidentaliol A (2). The 6-O-(a-l-rhamnopyranosyl-
(
2
1 ! 6)-b-d-glucopyranosyl)emodin (1) exhibited moderate anti-HIV-1 activity with an EC5 value of
0
.90 mg/ml and a therapeutic-index (TI) value of 260.
Introduction. – Cassia occidentalis L. (Leguminaceae) is used as traditional
medicine in the tropical areas of the world. A wide range of the chemical constituents
have been isolated from C. occidentalis, including sennoside, anthraquinone glycosides,
fatty oils, flavonoid glycosides, gallactomannan, polysaccharides, and tannins [1]. In
China, C. occidentalis L., named Wangjiangnan, was used for the treatment of some
diseases such as cough, asthma, and headache [2]. As one part of our investigations on
antiviral natural products from plants [3], the chemical constituents of C. occidentalis
was studied, which led to the isolation of one new anthraquinone glycoside, 6-O-(a-l-
1
rhamnopyranosyl-(1 ! 6)-b-d-glucopyranosyl)emodin ) (1), two new sesquilignans,
1
1
seslignanoccidentaliols A ) (2) and B ) (3), together with two known anthraquinones,
emodin (¼1,3,8-trihydroxy-6-methylanthracene-9,10-dione; 4) and physcion (5), and
five known lignans, threo-buddlenol B (6), erythro-buddlenol B (7), threo-buddlenol C
(
8), erythro-buddlenol C (9), and hedyotisol A (10), from the AcOEt part of MeOH
extracts of the plant. Among them, 6-O-(a-l-rhamnopyranosyl-(1 ! 6)-b-d-glucopyr-
anosyl)emodin (1) showed moderate inhibitory activity against HIV-1. This article
reports the structure elucidation of the new compounds as well as the bioassay results.
1)
Arbitrary or trivial atom numbering, for systematic names, see Exper. Part.
ꢀ
2010 Verlag Helvetica Chimica Acta AG, Zꢁrich

1
796
Helvetica Chimica Acta – Vol. 93 (2010)
Results and Discussion. – Compound 1 was isolated as an orange-brown amorphous
solid. The molecular formula of 1 was determined to be C H O on the basis of
2
7
30 14
ꢀ
negative-ion-mode HR-ESI-MS (m/z 613.1326 ([M þ Cl] )). The IR spectrum showed
ꢀ
1
ꢀ1
absorption bands of OH (3431 cm ) and chelated C¼O (1628 cm ) groups.
Compound 1 was established as 6-O-(a-l-rhamnopyranosyl-(1 ! 6)-b-d-glucopyrano-
syl)emodin (1) by an extensive 1D- and 2D-NMR study and by comparison with
spectral data of compound 4.
The 13C-NMR (Table 1) spectra of 1 showed the prescence of 27 C-atoms
comprising two Me, one CH , and fourteen CH groups and ten quaternary C-atoms. In
2
13
the C-NMR spectra of 1, the signals due to the aglycone moiety were in good
agreement with those of emodin (4), except for glycosylation shifts of the signals of
C(5) (Dd ¼ þ1.2), C(6) (Dd ¼ ꢀ1.7), and C(7) (Dd ¼ þ0.4), suggesting that the sugar
moiety was linked to C(6) of the aglycone. Furthermore, in the NMR spectra of 1, two
anomeric C-atoms were identified at d(C) 100.6 and 99.8, correlating with the anomeric
H-atoms at d(H) 5.11 and 4.49, respectively, which indicated that compound 1 was a
emodin 6-glycosylglycoside. The sequential assignments of H- and C-atom resonances
of each monosaccharide were carried out by analysis of the 2D-NMR data from COSY,
HSQC, HMBC (Fig. 1), and ROESY experiments, as well as by their m pattern and

Helvetica Chimica Acta – Vol. 93 (2010)
1797
Table 1. 1H- (400 MHz) and 13C-NMR (100 MHz) Data of 1 ) and 4 ) in (D )DMSO. d in ppm, J in Hz.
1
1
6
1
4
d(H)
d(C)
d(H)
d(C)
C(1)
161.5
124.3
148.7
120.8
109.0
163.8
109.1
164.1
190.2
181.2
134.9
110.9
113.6
133.0
21.6
161.3
123.9
148.0
120.3
107.8
165.5
108.7
164.3
189.5
181.1
134.9
HꢀC(2)
7.20 (br. s)
7.16 (br. s)
C(3)
HꢀC(4)
HꢀC(5)
C(6)
7.55 (br. s)
7.23 (d, J ¼ 2.3)
7.49 (br. s)
7.12 (d, J ¼ 2.4)
HꢀC(7)
6.92 (d, J ¼ 2.3)
6.59 (d, J ¼ 2.4)
C(8)
C(9)
C(10)
C(11)
C(12)
C(13)
C(14)
a
)
113.2
132.6
21.4
MeꢀC(3)
2.42 (s)
Glc:
HꢀC(1’)
HꢀC(2’)
HꢀC(3’)
HꢀC(4’)
HꢀC(5’)
5.11 (d, J ¼ 7.0)
3.59 – 3.62 (m)
3.29 – 3.32 (m)
3.14 – 3.15 (m)
3.13 (overlapped)
3.84 (d, J ¼ 9.7),
99.8
73.1
76.2
69.8
75.8
66.1
CH (6’)
2
3
.39 (overlapped)
Rha:
HꢀC(1’’)
HꢀC(2’’)
HꢀC(3’’)
HꢀC(4’’)
HꢀC(5’’)
Me(6’’)
4.49 (br. d, J ¼ 7.3)
3.61 (overlapped)
3.45 – 3.47 (m)
100.6
70.3
70.7
72.1
68.3
17.9
3.08 – 3.12 (m)
3.37 (overlapped)
1.06 (d, J ¼ 6.2)
a) Undiscovered.
1
Fig. 1. Key HMBC (H ! C) data of 1 )
1
coupling constants in the H-NMR spectrum. The sugar units were identified as an a-l-
rhamnopyranosyl (Rha) and a b-d-glucopyranosyl (Glc) unit [4]. In addition, acid
hydrolysis of 1 produced l-rhamnose and d-glucose as sugar residues, as determined by
GC analysis. A HMBC between C(6) on the aglycone and the HꢀC(1) of Glc
confirmed that the sugar chain was linked at C(6). The linkage of Rha to C(6’) of Glc
was supported by a HMBC between HꢀC(1’’) at d(H) 4.49 (br. d, J ¼ 7.3 Hz) and C(6’)

1
798
Helvetica Chimica Acta – Vol. 93 (2010)
at d(C) 66.1. Thus, compound 1 was identified to be 6-O-(a-l-rhamnopyranosyl-(1 !
6
)-b-d-glucopyranosyl)emodin.
Compound 2 was obtained as a white powder. It had the molecular formula
C H O as deduced from the positive-ion-mode HR-ESI-MS (m/z 609.2311
3
1
38 11
þ
þ
ꢀ1
(
[M þ Na] , C H O Na ). Its IR spectrum showed absorptions of OH (3432 cm )
31
38 11
ꢀ1 1
and aromatic moieties (1596, 1516, and 1462 cm ). The H-NMR data of 2 (Table 2)
indicated the presence of one 1,3,4,5-tetrasubstituted benzene ring (d(H) 6.74 (br. s,
2
H, HꢀC(2’,6’))) [5], two 1,3,4-trisubstituted benzene moieties (d(H) 6.67 (dd, J ¼ 7.8,
1
1
.8 Hz, 1 H), 6.74 (br. s, 1 H), and 6.84 (d, J ¼ 1.8 Hz, 1 H); d(H) 6.83 (d, J ¼ 1.7 Hz,
H), 6.79 (br. s, 1 H), and 7.05 (br. s, 1 H)), and four MeO and three CH O groups.
2
1
1
From
the
H, H-COSY
data
(Fig. 2),
four
partial
structures
a
(C(7)ꢀC(8)(C(9))ꢀC(8’)(C(9’))ꢀC(7’)), b (C(7’’)ꢀC(8’’)ꢀC(9’’)), c (C(5)ꢀC(6)),
and d (C(5’’)ꢀC(6’’)) were deduced. Among them, the partial structure consisting of a
tetrahydrofuran ring was supported by the HMBC (Fig. 2) of HꢀC(9) to C(7’). The
correlations of HꢀC(7) to C(1), C(2), and C(6), and of HꢀC(7’) to C(1’) and C(2’,6’)
indicated that partial structure a was connected to C(1) and C(1’). In addition, partial
structure b (ꢂguaiacylglycerylꢃ (¼2-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-1-(hy-
droxymethyl)ethyl) moiety) was conncected to C(4’) via an ether bridge as shown by
the correlation of HꢀC(8’’) to C(4’). The relative configuration of HꢀC(8)/HꢀC(8’)
and HꢀC(7’)/HꢀC(8’) were confirmed to be trans by the obvious correlations
HꢀC(8’)/H ꢀC(7), and HꢀC(7’)/HꢀC(8) in the ROESY plot (Fig. 3), and an
a
erythro-configuration of HꢀC(7’’)/HꢀC(8’’) was determined by the J value of
HꢀC(7’’) (d, J ¼ 4.4 Hz) [6]. Thus, the structure of seslignanoccidentaliol A (2) was
established as shown.
Fig. 2. Selected 2D-NMR correlations of 2 and 31)
In the literature [7], however, a natural product, named erythro-guaiacylglycerol-b-
O-4’-(5’)-methoxylariciresinol, with the same planar structure as 2 was found. Almost
1
13
the same H- and C-NMR data suggested that both compounds should have the same

Helvetica Chimica Acta – Vol. 93 (2010)
1799
Table 2. 1H- and 13C-NMR Data of Compounds 2 and 3. d in ppm, J in Hz.
2a
)
3 )
b
d(H)
d(C)
d(H)
d(C)
C(1)
133.2
112.9
147.9
145.6
115.7
121.7
33.4
128.4
107.3
148.4
142.0
148.4
107.3
198.1
HꢀC(2)
6.84 (d, J ¼ 1.8)
7.41 (br. s)
7.41 (br. s)
C(3)
C(4)
HꢀC(5)
6.74 (br. s)
HꢀC(6)
6.67 (dd, J ¼ 7.8, 1.8)
2.93 (dd, J ¼ 16.8, 6.3)
2.54 (dd, J ¼ 16.8, 13.8)
2.66 – 2.75 (m)
H ꢀC(7)
a
H ꢀC(7)
b
HꢀC(8)
43.4
73.3
4.27 – 4.31 (m)
4.22 (br. s)
4.21 (d, J ¼ 2.8)
49.7
71.1
H ꢀC(9)
4.00 (dd, J ¼ 10.5, 8.5)
a
H ꢀC(9)
3.70 – 3.75 (m)
b
C(1’)
141.5
103.6
153.9
135.1
153.9
103.6
83.5
139.3
104.5
154.0
135.6
154.0
104.5
84.1
HꢀC(2’)
6.74 (br. s)
6.79 (br. s)
C(3’)
C(4’)
C(5’)
HꢀC(6’)
HꢀC(7’)
HꢀC(8’)
6.74 (br. s)
6.79 (br. s)
4.90 (d, J ¼ 5.6)
2.31 – 2.38 (m)
3.87 – 3.93 (m)
3.72 (overlapped)
4.71 (d, J ¼ 7.6)
2.63 – 2.68 (m)
3.73 (d, J ¼ 5.2)
53.8
60.4
54.7
61.2
H ꢀC(9’)
a
H ꢀC(9’)
b
C(1’’)
133.7
110.8
148.2
146.4
115.2
119.9
73.3
133.7
110.7
147.9
146.3
115.1
120.0
73.1
HꢀC(2’’)
7.05 (br. s)
7.03 (d, J ¼ 1.6)
C(3’’)
C(4’’)
HꢀC(5’’)
HꢀC(6’’)
HꢀC(7’’)
HꢀC(8’’)
6.79 (br. s)
6.83 (d, J ¼ 1.7)
4.98 (br. d J ¼ 4.4 )
4.14 – 4.18 (m)
3.87 (overlapped)
3.42 – 3.51 (m)
3.84 (s)
6.77 (br. s)
6.83 (overlapped)
4.97 (d, J ¼ 4.4)
4.13 – 4.16 (m)
3.82 (overlapped)
3.41 (dd, J ¼ 12.0, 2.8)
3.89 (s)
3.89 (s)
3.85 (s)
3.82 (s)
87.8
60.8
87.8
60.8
H ꢀC(9’’)
a
H ꢀC(9’’)
b
MeOꢀC(3)
MeOꢀC(5)
MeOꢀC(3’,5’)
MeOꢀC(3’’)
56.1
–
56.4
56.1
56.6
56.6
56.5
56.1
–
3.85 (s)
3.82 (s)
a) In CD OD. ) In (D )Acetone.
b
3
6
relative configuration. However, the relative configuration of HꢀC(8)/HꢀC(8’) in [7]
was determined to be cis only by a HꢀC(8)/HꢀC(8’) correlation in the NOESY plot,
which is opposite to our experiment. Since HꢀC(8) and HꢀC(8’) are vicinal H-atoms
and their NOE correlation for conformational analysis is unreliable, we consider that
the relative cis-configuration of HꢀC(8)/HꢀC(8’) in [7] is wrong, and should be trans.
Moreover, the 1D-NMR spectroscopic data of the tetrahydrofuran moiety of 2
(
Table 2) were almost identical to those of lignans with the same moiety, which also
supported our results [8 – 10].

1
800
Helvetica Chimica Acta – Vol. 93 (2010)
1
Fig. 3. Key ROESY (H $ H) correlations of 2 )
Compound 3 was obtained as a white, optically active powder. It exhibited an [M þ
þ
Na] ion peak at m/z 653.2210 in the positive-ion mode HR-ESI-MS, corresponding to
the molecular formula C H O . The IR spectrum displayed absorption bands of OH
3
2
38 13
ꢀ
1
ꢀ1
1
13
(
3440 cm ) and aromatic moieties (1639, 1512, and 1461 cm ). Its H- and C-NMR
spectroscopic data (Table 2) were similar to those of compound 2 indicating that 3 was
13
a sesquilignan. Comparison of the C-NMR spectrum of compound 3 with that of 2
2
showed that 3 had an additional C¼O group at d(C) 198.1, an sp quatenary C-atom
3
2
(
d(C) 148.4) and one more MeO group, in place of an sp CH (d(C) 33.4) and an sp
2
1
13
CH group (d(C) 115.7) in 2. Comprehensive analysis of the H- and C-NMR data and
D-NMR spectra of 3, especially H, H-COSY, HMQC, HMBC, and ROESY,
1
1
2
elucidated the structure of 3. Thus HMBCs (Fig. 2) from HꢀC(2), HꢀC(6), and
HꢀC(8’) to C(7) (d(C) 198.1) indicated that the C¼O group was located at C(7), while
the additional MeO was at C(5) due to the HMBC of MeOꢀC(5) to C(5). The
remaining structure and relative configuration of 3 were identical to those of 2 as
determined by HMBC (Fig. 2) and ROESY NMR experiments. In 1982, Nakatsubo
and co-workers [11] reported the acetylation product of 3 in a study on the degradation
process of trimeric lignin model compounds on a fungus. They speculated the presence
of compound 3 as an intermediate in the reaction system but did not obtained it. The
isolation and structure elucidation of compound 3 is reported for the first time.
The seven known compounds were identified as emodin (4) [12], physicon (5) [12],
threo-buddlenol B (6) [6][13], erythro-buddlenol B (7) [6][13], threo-buddlenol C (8)
[
6][14], erythro-buddlenol C (9) [6][14], and hedyotisol A (10) [13] by comparison of
their spectroscopic data with literature data.
Compound 1 was tested for cytotoxicity against C8166 cells (CC ) and showed
50
moderate cytotoxic activity with a CC value of 756 mg/ml. Its anti-HIV-1 activity was
50
evaluated by an inhibition assay for the cytopathic effects of HIV-1 (EC ), with AZT
50
as a positive control. Compound 1 showed anti-HIV-1 activity with an EC50 value of
2.90 mg/ml and a therapeutic-index (TI) value of 260.
This work was supported by the National Natural Science Foundation of China (30760306) and the
Yunnan Provincial Science Foundation (2006C009Z).

Helvetica Chimica Acta – Vol. 93 (2010)
1801
Experimental Part
General. Column chromatography (CC): silica gel (SiO ; 200 – 300 mesh, 10 – 40 mm; Qingdao
2
Haiyang Chemical Factory, China); RP-C18 reversed-phase SiO (40 – 63 mm; Daiso Co., Japan), and
2
Sephadex LH-20 (Amersham Pharmacia Biotech, Sweden). HPLC: Agilent-1100 workstation Zorbax-
SB-C18 column (250 ꢁ 9.4 mm); DAD detector). GC: HP5890 (Agilent, America) with a quartz cap.
column (30 mm ꢁ 0.32 mm ꢁ 0.25 mm); FID detection. Optical rotations: Horiba-SEPA-300 polarimeter
or Jasco-DIP-370 digital polarimeter. UV Spectra: Shimadzu-UV-2401PC spectrometer; l in nm. IR
max
ꢀ
1
Spectra: Bio-Rad-FTS-135 spectrometer; KBr pellets; ˜n in cm . 1D- and 2D-NMR Spectra: DRX-500 or
Bruker-AM-400 spectrometer; d in ppm, J in Hz; Me Si as internal standard. ESI- and HR-ESI-MS: VG-
4
Auto-Spec-3000 spectrometer; in m/z (rel. %).
Plant Material. The whole plant of C. occidentalis, collected in Xishuangbanna of Yunnan Province,
P. R. China, in October 2007, was identified by Prof. Jing-Yun Cui, Xishuangbanna Tropical Botanical
Garden, Chinese Academy of Sciences.
Extraction and Isolation. The whole air-dried plant of C. occidentalis (12.0 kg) was extracted with
MeOH under refluxing to give a crude extract. After removal of the solvent by evaporation, the residue
was suspended in H O and then extracted successively with petroleum ether, AcOEt, and BuOH. The
2
AcOEt extract was concentrated to yield a residue (300 g). Then, this residue was subjected to CC (SiO2,
CHCl /MeOH 10 :1, 5 :1, 1:1, and 0 :1): Fractions 1 – 4. Fr. 1 was subjected repeatedly to CC (RP-C and
3
18
SiO ): 4 (15.0 mg) and 5 (5.0 mg). Fr. 2 was subjected repeatedly to CC (RP-C and SiO ): Frs. 2A – 2E.
2
18
2
Fr. 2C was subjected to repeated CC (SiO , CHCl /MeOH 7:1 and 3 :1): Frs. 2C1 – 2C5. Further
2
3
purification of Frs. 2C2 and 2C3 by CC (Sephadex LH-20) and semi-prep. HPLC yielded 2 (8.0 mg), 3
6.0 mg), 6 (10.0 mg), and 7 (10.0 mg). Compounds 8 – 10 were obtained by the same procedures from
(
Fr. 2C4. Fr. 2C5 was purified by recrystallization and repeated CC (SiO ): 1 (15.0 mg).
2
Acid Hydrolysis of 1. Compound 1 (5.0 mg) was refluxed with 1m HCl/dioxane 1:1 (v/v, 2 ml) at 808
for 3 h. The mixture was neutralized with 1m NaOH and filtered. The filtrate was extracted with CHCl3
and H O, and then the H O-souble fraction was concentrated. The dried sugar residue was diluted in abs.
2
2
pyridine (1 ml), l-cysteine methyl ester hydrochloride (1.5 mg) was added, and the mixture was heated at
08 for 1 h. Then 1-(trimethylsilyl)-1H-imidazole (1.5 ml) was added, and the mixture was heated at 608
6
for another 30 min. An aliquot (4 ml) of the supernatant was removed and directly subjected to GC
analysis (column temp. 180 – 2808 at 38/min, carrier gas N (1 ml/min), injector and detector temp. 2508,
2
split ratio 1:50). The configurations of l-rhamnose and d-glucose for 1 were determined by comparison
of the retentions times of the corresponding derivatives with standard l-rhamnose and d-glucose, giving
single peaks at tR 15.826 and 19.208 min, resp.
6
-O-(a-l-Rhamnopyranosyl-(1 ! 6)-b-d-glucopyranosyl)emodin (¼ 3-{[6-O-(6-Deoxy-a-l-manno-
pyranosyl)-b-d-glucopyranosyl]oxyl}-1,8-dihydroxyanthracene-9,10-dione; 1): Orange-brown amor-
1
9:2
phous solid. [a] ¼ ꢀ124.3 (c ¼ 0.18, MeOH). UV (MeOH): 505, 304, 258, 237, 226, 202. IR (KBr):
D
1
13
3
431, 2922, 1628, 1479, 1387, 1263, 1217, 1067. H- and C-NMR: Table 1. HR-ESI-MS: 613.1326 ([M þ
ꢀ ꢀ
Cl] , C H O Cl ; calc. 613.1324).
27
30 14
Seslignanoccidentaliol A (¼ rel-(1R,2S)-2-{2,6-Dimethoxy-4-{(2S,3R,4S)-tetrahydro-4-[(4-hydroxy-
3
-methoxyphenyl)methyl]-3-(hydroxymethyl)furan-2-yl}phenoxy}-1-(4-hydroxy-3-methoxyphenyl)pro-
2
7:2
pane-1,3-diol; 2): White powder. [a]
D
¼ 0.0 (c ¼ 0.15, MeOH). UV (MeOH): 280, 204. IR (KBr): 3432,
1 13
2
(
937, 1596, 1516, 1462, 1425, 1273, 1235, 1123, 1034. H- and C-NMR: Table 2. HR-ESI-MS: 609.2312
þ
þ
[M þ Na] , C H O Na ; calc. 609.2311).
31
38 11
Seslignanoccidentaliol B (¼ rel-(4-Hydroxy-3,5-dimethoxyphenyl){(3R,4S,5R)-tetrahydro-5-{4-
[
4
(1R,2S)-2-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-1-(hydroxymethyl)ethoxy]-3,5-dimethoxyphenyl}-
-(hydroxymethyl)furan-3-yl)methanone; 3): White powder. [a] 2D 4:1 ¼ þ33.3 (c ¼ 0.09, MeOH). UV
(
MeOH): 301, 283, 205. IR (KBr): 3440, 2926, 1711, 1639, 1512, 1462, 1424, 1378, 1352, 1280, 1123, 1034.
1
13
þ
þ
H- and C-NMR: Table 2. HR-ESI-MS: 653.2190 ([M þ Na] , C H O Na ; calc. 653.2210).
32
38 13
Anti-HIV-1 Assay. The cytotoxicity assay against C8166 cells (CC ) was assessed by using the MTT
50
(
¼2-(4,5-dimethylthiazol-2-yl)-3,5-diphenyl-2H-tetrazolium bromide) method, and the anti-HIV-1
activity was evaluated by the inhibition assay for the cytopathic effects of HIV-1 (EC ) [15].
50

1
802
Helvetica Chimica Acta – Vol. 93 (2010)
REFERENCES
[
[
[
1] J. C. Chukwujekwu, P. H. Coombes, D. A. Mulholland, J. van Staden, S. Afr. J. Bot. 2006, 72, 295.
2] Editorial Committee, ꢂChinese Bencaoꢃ, Shanghai Science and Technology Press, 1999, Vol. 4, p. 410.
3] Y. Li, L. Wang, S. Li, X. Chen, Y. Shen, Z. Zhang, H. He, W. Xu, Y. Shu, G. Liang, R. Fang, X. Hao,
Proc. Natl. Acad. Sci. U.S.A. 2007, 104, 8083; Y.-H. Wang, Z.-K. Zhang, F.-M. Yang, Q.-Y. Sun, H.-P.
He, Y.-T. Di, S.-Z. Mu, Y.-Lu, Y. Chang, Q.-T. Zheng, M. Ding, J.-H. Dong, X.-J Hao, J. Nat. Prod.
2
007, 70, 1458.
4] H. Yoshimitsu, M. Nishida, F. Hashimoto, M. Tanaka, Y. Sakata, M. Okawa, T. Nohara, J. Nat. Med.
007, 61, 334.
5] X.-W. Yang, P.-J. Zhao, Y.-L. Ma, H.-T. Xiao, Y.-Q. Zuo, H.-P. He, L. Li, X.-J. Hao, J. Nat. Prod. 2007,
0, 521.
6] T. Miyase, A. Ueno, N. Takizawa, H. Kobayashi, H. Oguchi, Chem. Pharm. Bull. 1987, 35, 3713; C. H.
Ludwig, B. J. Nist, J. L. McCarthy, J. Am. Chem. Soc. 1964, 96, 1186; G. D. Manners, E. P. Swan, Can.
J. Chem. 1971, 49, 3607; K. Kijima, H. Otsuka, T. Ide, C. Ogimi, E. Hirata, A. Takushi, Y. Takeda,
Phytochemistry 1998, 48, 669.
[
[
[
2
7
[
[
7] H.-Y. Han, H.-W. Liu, N.-L. Wang, X.-S. Yao, Nat. Prod. Res. 2008, 22, 984.
8] J. Lee, D. Lee, D. S. Jang, J.-W. Nam, J.-P. Kim, K. H. Park, M. S. Yang, E.-K. Seo, Chem. Pharm.
Bull. 2007, 55, 137.
[
9] J. Lee, E.-K. Seo, D. S. Jang, T. J. Ha, J.-P. Kim, J.-W. Nam, G. Bae, Y. M. Lee, M. S. Yang, J. S. Kim,
Chem. Pharm. Bull. 2009, 57, 298.
[
[
[
[
[
[
10] R.-Q. Mei, Y.-H. Wang, G.-H. Du, G.-M. Liu, L. Zhang, Y.-X. Cheng, J. Nat. Prod. 2009, 72, 621.
11] Y. Kamaya, F. Nakatsubo, T. Higuchi, Agric. Biol. Chem. 1983, 47, 299.
12] S. N. Ram, S. P. D. Dwivedi, V. B. Pandey, A. H. Shah, Fitoterapia 1988, 59, 78.
13] P. J. Houghton, Phytochemistry 1985, 24, 819.
14] S. Matsuda, S. Kadota, T. Tai, T. Kikuchi, Chem. Pharm. Bull. 1984, 32, 5066.
15] J. H. Wang, S. C. Tam, H. Huang, D.-Y. Ouyang, Y.-Y. Wang, Y.-T. Zheng, Biochem. Biophys. Res.
Commun. 2004, 317, 965.
Received December 18, 2009