Pentasaccharide glycosides from the tubers of sweet potato (Ipomoea batatas)

Article abstract of DOI:10.1021/jf0733463

Sweet potato (Ipomoea batatas) has been used as food and herb in many countries. In this research on the active constituents of sweet potato, nine compounds were isolated and identified, including seven new resin glycosides, batatosides A-G (1-7), along with two known compounds, batatinoside I (8) and simonin IV (9). The structures of 1-9 have been established by a combination of spectroscopic and chemical methods. The major characteristics of the new compounds are the presence of three different substituents. The absolute configuration of aglycones was established as S by Mosher's method. Batatoside E (5) showed weak cytotoxic activity against Hep-2 cells.

Full text of DOI:10.1021/jf0733463

J. Agric. Food Chem. 2008, 56, 2363–2368 2363
Pentasaccharide Glycosides from the Tubers of
Sweet Potato (Ipomoea batatas)
YONGQIN YIN,† YI LI,‡ AND LINGYI KONG*,†
Department of Natural Medicinal Chemistry, China Pharmaceutical University, 24 Tong Jia Xiang,
Nanjing 210009, People’s Republic of China, and Analytical and Testing Center, Nanjing Normal
University, 122 Ning Hai Road, Nanjing 210097, People’s Republic of China
Sweet potato (Ipomoea batatas) has been used as food and herb in many countries. In this research
on the active constituents of sweet potato, nine compounds were isolated and identified, including
seven new resin glycosides, batatosides A-G (1–7), along with two known compounds, batatinoside
I (8) and simonin IV (9). The structures of 1–9 have been established by a combination of spectroscopic
and chemical methods. The major characteristics of the new compounds are the presence of three
different substituents. The absolute configuration of aglycones was established as S by Mosher’s
method. Batatoside E (5) showed weak cytotoxic activity against Hep-2 cells.
KEYWORDS: Ipomoea batatas; resin glycoside; cinnamic acid; batatoside
INTRODUCTION
MATERIALS AND METHODS
General Procedures. Optical rotations were measured with a JASCO
P-1020 polarimeter. UV and IR spectra were recorded with Shimadzu
UV-2501PC and Nicolet Impact 410 spectrometers, respectively. 1H
and 13C NMR, HSQC, HMBC, and TOCSY spectra were taken with
Bruker ACF-600 spectrometers (600 and 150 MHz, respectively) in
pyridine-d5; chemical shifts are reported in parts per million as δ relative
to Me4Si (internal standard). Mass spectra were obtained on an MS
Agilent 1100 series LC/MSD ion trap mass spectrometer (ESIMS), and
HR-ESIMS were recorded with an Agilent TOF MSD 1946D spec-
trometer. TLC was performed on precoated silica gel 60 F254 (Qingdao
Marine Chemical Co. Ltd.) and detected by spraying with 10% H2SO4/
EtOH. Column chromatography was carried out with silica gel H
(Qingdao Marine Chemical Co. Ltd.), Sephadex LH-20 (20–100 µ,
Pharmacia), and ODS-C18 (100–200 µ, Waters). Preparative HPLC was
carried out using an Agilent 1100 series instrument with a 200 mm ×
20 mm i.d. Shimpak RP-C18 column (Shimadzu) and UV detector at
280 nm.
Plant Material. The tubers of I. batatas were collected in Yanlin
County, Hunan Province, People’s Republic of China, in September
2004 and identified by Prof. Min-jian Qin, Department of Medicinal
Plants, China Pharmaceutical University. A voucher specimen (No.
040912) was deposited in the Department of Natural Medicinal
Chemistry, China Pharmaceutical University.
Extraction and Isolation. Tubers (18 kg) of I. batatas were crushed
and dried in the shade for 1 week. The pieces were extracted with 95%
EtOH (3 × 20 L × 2 h) at 80 °C, and the extraction solution was
concentrated under a vacuum and allowed to stand overnight. The
solution was further concentrated to produce a residue, which was
partitioned between CHCl3 (5 × 0.5 L) and water (0.5 L) to give 45
and 18 g of extracts from these two layers, respectively. The CHCl3
extract was subjected to chromatography on a 60 cm × 5 cm 200–300
mesh silica gel (300 g), eluted with CHCl3/MeOH (100:3f100:50).
Fractions of 245-272 (1.8 g) eluted with CHCl3/MeOH (100:10) were
further submitted to chromatography on a 30 cm × 1.5 cm (60 µm)
RP-C18 and eluted with MeOH/H2O (90:10f100:0) to afford fraction
1 (0.3 g) with 90:10 MeOH/H2O, fraction 2 (0.9 g) with 95:5 MeOH/
Ipomoea batatas (L.) Lam. (Convolvulaceae) with the com-
mon name of sweet potato is also known as “shanyu”,
“hongshu”, “digua”, and “hongshao” in mainland of China. The
colors of the peel and flowers of sweet potato are different
depending on the location of growth. The aerial part of the sweet
potato is used as a vegetable and the underground part is used
as food or a raw material in industry (1). Scammony root
(ConVolVulus scammonia) of Mexican jalaps, which was
introduced to Europe by Spanish colonists, was utilized as a
purgative medicine (2, 3). The antibacterial activities of the 22
oligosaccharides from Ipomoea tricolor and Ipomoea orizabensis
were evaluated against a panel of Staphylococcus aureus strains
possessing or lacking specific efflux pumps (4). One of the six
pentasaccharides from Ipomoea murucoides exhibited marginal
cytotoxicity against Hep-2 cells (5). In Chinese traditional
medicine, the tubers of I. batatas have been used as a medicinal
herb to promote the production of body fluids, hemostasis, and
apocenosis (6). Recently, two new ester-type dimer resin
glycosides were described from I. batatas tubers collected in
Mexico (7). Considering the usage as food and vegetable as
well as pharmacological activities of I. batatas, we have been
encouraged to investigate the constituents further. This study
was designed to isolate and structurally elucidate new resin
glycosides batatosides A (1)-G (7) as well as known resin
glycosides batatinoside I (8) and simonin IV (9) and to
investigate the cytotoxic activity of these compounds against
Hep-2 cells.
* Author to whom correspondence should be addressed (telephone
+86 25 85391289; fax +86 25 85301528; e-mail lykong@
jlonline.com).
† China Pharmaceutical University.
‡ Nanjing Normal University.
10.1021/jf0733463 CCC: $40.75  2008 American Chemical Society
Published on Web 03/15/2008

2364 J. Agric. Food Chem., Vol. 56, No. 7, 2008
Yin et al.
H2O, and fraction 3 (0.6 g) with MeOH, respectively. Using preparative
HPLC (UV detector at 280 nm) over a C18 column, two peaks were
collected from fraction 1 eluted with 91% MeOH/H2O, to afford
batatoside A (1, 4.5 mg, tR 8.25 min) and batatoside B (2, 3.8 mg, tR
9.54 min). Fraction 2 afforded batatoside C (3, 18.4 mg, tR 11.10 min),
batatoside F (6, 15.6 mg, tR 5.91 min), batatoside G (7, 8.7 mg, tR 5.36
min), batatinoside I (8, 26.0 mg, tR 7.91 min), and simonin IV (9, 46.2
mg, tR 19.60 min), when eluted with 95% MeOH/H2O. Fraction 3 gave
batatoside D (4, 208.4 mg, tR 24.50) and batatoside E (5, 361.3 mg, tR
22.00min), when eluted with 98% MeOH/H2O.
Table 1. 13C NMR Data of Compounds 1–7 (C5D5N, 150 MHz)a
carbonb
1
2
3
4
5
6
7
Fuc-1
2
3
4
5
6
Rha-1
2
3
4
101.7
73.6
76.6
73.7
71.3
17.2
100.3
69.9
77.9
77.6
68.0
18.8
99.0
72.9
79.6
79.1
68.5
18.7
100.4
71.2
73.1
71.3
70.9
18.9
104.5
72.3
72.6
73.6
70.8
19.1
174.8
33.8
79.6
14.5
166.5
118.3
146.1
176.5
34.4
19.2
18.3
175.4
41.5
17.0
11.9
101.4
73.6
76.6
73.6
71.3
17.2
100.2
69.9
78.0
77.3
68.2
18.8
99.1
72.8
79.6
80.7
68.5
19.2
103.8
70.1
73.3
71.6
68.2
17.7
104.5
72.7
72.6
73.6
70.7
18.9
174.8
33.8
79.6
14.5
166.2
118.4
145.4
176.3
34.5
18.8
19.2
101.7
73.6
76.6
73.7
71.2
17.2
100.2
69.8
77.8
77.7
68.0
18.8
99.0
72.9
79.8
79.1
68.5
18.7
100.3
71.2
73.0
71.3
70.8
19.1
104.5
72.3
72.4
73.6
70.8
19.2
173.3
33.8
79.6
14.3
166.6
118.3
146.0
104.3
80.7
73.5
73.1
70.6
17.4
98.7
73.5
69.8
80.3
70.8
19.4
99.4
72.9
79.4
80.1
68.3
18.9
103.6
70.1
73.9
71.7
68.5
17.8
104.3
72.6
72.5
73.2
68.6
18.5
173.1
34.3
82.4
14.3
166.4
118.4
145.5
104
80.3
104.3
80.3
73.3
73.0
70.8
17.4
98.8
73.8
69.7
80.8
70.7
19.4
99.3
73.1
78.5
79.4
68.6
18.9
100.2
71.2
73.6
73.1
70.8
18.6
104.5
72.3
72.6
73.6
68.4
18.3
173.1
33.2
82.4
14.3
166.6
118.3
146.1
104.3
80.3
73.2
73.0
70.8
17.4
98.8
73.9
69.7
80.7
70.7
18.9
99.4
73.1
80.2
79.7
68.2
19.2
103.6
70.3
73.4
71.6
68.4
18.6
104.5
72.7
72.6
73.2
68.7
17.7
173.1
34.4
82.4
14.3
166.4
118.3
145.6
73.4
73.0
70.8
17.4
98.8
73.9
69.9
80.3
68.2
19.5
99.1
73.1
79.0
80.1
68.6
18.9
100.3
74.1
68.2
75.2
68.5
18.0
104.8
72.2
72.6
73.5
68.6
18.6
173.1
33.2
82.4
14.3
166.8
118.5
145.6
Batatoside A (1): amorphous white powder; mp 122–124 °C; [R]D25
-11.6 (c 0.55, MeOH); IR νmax (KBr) 3443, 2934, 2859, 1722, 1637,
1
1137, 1097 cm-1; UV (MeOH) λmax (log ꢀ) 280 (4.17) nm; H NMR
5
6
(C5D5N, 600 MHz) and 13C NMR (C5D5N, 150 MHz) data, see Tables
1 and 2; ESIMS m/z 1267 [M - H]-; HRESIMS m/z 1267.6425 [M -
H]- (calcd for C64H99O25, 1267.6475).
Rha′-1
2
3
4
5
6
Rha′′-1
2
3
4
5
6
Rha′′′-1
2
3
4
5
6
Ag-1
2
11
16
Cna-1
Batatoside B (2): amorphous white powder; mp 119–121 °C; [R]D25
-12.1 (c 0.50, MeOH); IR νmax (KBr) 3444, 2929, 2856, 1722, 1637,
1136 cm-1; UV (MeOH) λmax (log ꢀ) 280 (4.37) nm; 1H NMR (C5D5N,
600 MHz) and 13C NMR (C5D5N, 150 MHz) data, see Tables 1 and
2; ESIMS m/z 1253 [M - H]-; HRESIMS m/z 1253.5944 [M - H]-
(calcd for C63H97O25, 1253.6324).
Batatoside C (3): amorphous white powder; mp 109–111 °C; [R]D25
-22.0 (c 0.55, MeOH); IR νmax (KBr) 3444, 2931, 2857, 1737, 1636,
1
1137, 1064 cm-1; UV (MeOH) λmax (log ꢀ) 280 (4.27) nm; H NMR
(C5D5N, 600 MHz) and 13C NMR (C5D5N, 150 MHz) data, see Tables
1 and 2; ESIMS m/z 1415 [M + Cl]-; HRESIMS m/z 1415.7580 [M
+ Cl]- (calcd for C72H116ClO25, 1415.7494).
Batatoside D (4): amorphous white powder; mp 105–107 °C; [R]D25
-10.2 (c 0.15, MeOH); IR νmax (KBr) 3444, 2931, 2857, 1737, 1636,
1
1137, 1064 cm-1; UV (MeOH) λmax (log ꢀ) 280 (4.19) nm; H NMR
(C5D5N, 600 MHz) and 13C NMR (C5D5N, 150 MHz) data, see Tables
1 and 3; ESIMS m/z 1415 [M + Cl]-; HRESIMS m/z 1415.7487 [M
+ Cl]- (calcd for C72H116ClO25, 1415.7494).
Batatoside E (5): amorphous white powder; mp 115–117 °C; [R]D25
-20.0 (c 0.54, MeOH); IR νmax (KBr) 3445, 2929, 2857, 1725, 1636,
2
1
1136, 1070 cm-1; UV (MeOH) λmax (log ꢀ) 280 (4.04) nm; H NMR
3
Iba-1
2
(C5D5N, 600 MHz) and 13C NMR (C5D5N, 150 MHz) data, see Tables
1 and 3; ESIMS m/z 1415 [M + Cl]-; HRESIMS m/z 1415.7584 [M
+ Cl]- (calcd for C72H116ClO25, 1415.7494).
3
3′
Mba-1
2
CH3-2
4
Dodeca-1
2
12
Aa-1
2
Batatoside F (6): amorphous white powder; mp 110–112 °C; [R]D25
-23.1 (c 0.55, MeOH); IR νmax (KBr) 3442, 2928, 2856, 1728, 1635,
175.4
41.5
16.9
11.8
174.8
34.5
14.5
175.4
41.5
16.8
11.8
173.2
34.6
14.3
175.4
41.3
16.8
11.8
173.5
34.6
14.3
175.4
41.5
16.8
11.8
173.6
34.4
14.3
1
1135, 1070 cm-1; UV (MeOH) λmax (log ꢀ) 280 (3.90) nm; H NMR
(C5D5N, 600 MHz) and 13C NMR (C5D5N, 150 MHz) data, see Tables
1 and 3; ESIMS m/z 1415 [M + Cl]-; HRESIMS m/z 1415.7305 [M
+ Cl]- (calcd for C72H116ClO25, 1415.7494).
172.9
34.4
14.3
176.4
19.5
Batatoside G (7): amorphous white powder; mp 106–108 °C; [R]D25
-27.3 (c 0.17, MeOH); IR νmax (KBr) 3443, 2930, 2857, 1726, 1637,
1
1137, 1071 cm-1; UV (MeOH) λmax (log ꢀ) 280 (4.10) nm; H NMR
Ba-1
2
4
176.0
34.3
19.0
(C5D5N, 600 MHz) and 13C NMR (C5D5N, 150 MHz) data, see Tables
1 and 3; ESIMS m/z 1373 [M + Cl]-; HRESIMS m/z 1373.6898 [M
+ Cl]- (calcd for C69H110ClO25, 1373.7025).
Batatinoside I (8): amorphous white powder; mp 126–128 °C; [R]2D5
-9.7 (c 0.90, MeOH); IR νmax (KBr) 3444, 2931, 1737, 1636, 1137,
1064 cm-1; UV (MeOH) λmax (log ꢀ) 280 (4.13), 217 (3.98), 205 (3.97)
nm; ESIMS m/z 1415 [M + Cl]-, HRESIMS m/z 1415.7487 [M +
Cl]- (calcd for C72H116ClO25, 1415.7494); identified by comparison of
NMR data (1HNMR, 13CNMR, HSQC, HMBC, TOCSY) with pub-
lished values (7).
a Chemical shifts (δ) are in ppm relative to TMS. All assignments are based on
HMQC and HMBC experiments. b Abbreviations: Fuc, fucose; Rha, rhamnose; Ag,
11-hydroxyhexadecanoyl; Dodeca, n-dodecanoyl; Mba, (S)-2-methylbutanoyl; Iba,
isobutanoyl; Cna, trans-cinnamoyl; Ba, n-butanoyl; Aa, acetonoyl.
column (Varian); column temperature, 160–240 °C temperature pro-
grammed at 10 °C/min; carrier gas, N2 (30 mL/min). Peaks in the
chromatograms were detected from the hydrolysis mixtures and
identified by comparison with authentic samples as n-dodecanoyl acid
methyl ester (tR 14.020 min) m/z [M + H]+ 215 (23), 171 (31), 143
(55), 87 (85), 74 (100), 55 (86), 43 (96), 41 (56), from 3-7; trans-
cinnamic acid methyl ester (tR 12.498 min) m/z [M]+ m/z 162 (45),
131 (100), 103 (76), 77 (35), from 1-7; (S)-2-methylbutyric acid methyl
ester (tR 3.593 min) m/z [M + H]+ 117 (5), 101 (23), 88 (87), 57 (100),
41 (57), from 1-6; butyric acid methyl ester (tR 2.349 min) m/z [M -
H]- 101 (3), 74 (39), 71 (63), 43 (100), 41 (53), from 2; isobutyric
acid methyl ester (tR 2.368 min) m/z [M - H]- 101 (32), 87 (48), 71
(50), 43 (100), from 1; and acetic acid methyl ester (tR 2.100 min) m/z
[M - H]- 73 (57), 59 (100), 45 (75), 41 (58), from 7. The ether extract
Simonin IV (9): amorphous white powder; mp 122–124 °C; [R]D25
-48.0 (c 0.50, MeOH); IR νmax (KBr) 3451, 2976, 2935, 1737, 1638,
1137, 1060; ESIMS m/z 1249 [M - H]-; identified by comparison of
NMR data (1HNMR, 13CNMR) with published values (8).
Alkaline Hydrolysis of 1–7. Compounds 1–7 (3 mg each) in 5%
KOH (3 mL) were refluxed at 90 °C for 2 h, separately. The reaction
mixtures were acidified to pH 4 and extracted with ether (30 mL) and
n-BuOH (30 mL). The ether layer was washed with H2O, dried over
anhydrous Na2SO4, methylated with MeOH, and catalyzed with 0.5 N
H2SO4. The methyl esters were analyzed by GC-MS on a model 3800
GC interfaced with a model 2200 MS (Varian) at 70 eV under the
following conditions: 30 m × 0.25 mm i.d., 0.25 m, VF-5 ms capillary

Pentasaccharide Glycosides from Sweet Potato
J. Agric. Food Chem., Vol. 56, No. 7, 2008 2365
Table 2. 1H NMR Data of Compounds 1-3 (C5D5N, 600 MHz)a
reaction and filtered. The filtrate was concentrated and purified by silica
gel chromatography eluted with cyclohexane/ethyl acetate (95:5) to give
12 [2.6 mg, 94%; 11-(R-MPA)-hexadecanoic acid methyl ester].
Treatment of 11 with (S)-MPA by the same procedure yielded 13 [2.3
mg, 85%; 11-(S-MPA)-hexadecanoic acid methyl ester]. The chemical
protonb
1
2
3
Fuc-1
2
3
4.80, d (7.9)
4.80, d (7.9)
4.79, d (7.8)
4.51, dd (7.8, 9.4)
4.17 *
4.50, dd (7.9, 9.5)
4.16, dd (9.5, 3.4)
3.90, d (3.4)
4.51, dd (7.9, 9.5)
4.16, dd (9.5, 3.4)
3.90, d (3.4)
RS
RS
RS
shift differences of 12 and 13 (∆δ ) +0.06, ∆δ ) -0.13, ∆δ
H10
H12
H16
4
3.90 *
) -0.07 ppm) (10–14) made it possible to conclude the chiral C-11
of 11 is in the S configuration, the same as in the literature (15). The
n-BuOH layer of acid hydrolysis was neutralized by passage through
an ion-exchange resin (Amberlite MB-3) column and concentrated to
yield a saccharide residue, which was treated with water (0.05 mL)
and pyridine (0.03 mL) at 60 °C for 1 h with stirring. After the solvent
was evaporated and the reaction mixture was dried, pyridine (0.5 mL),
hexamethyldisilazane (0.8 mL), and trimethylsilyl chloride (0.4 mL)
were added to the residue. The reaction mixture was heated at 60 °C
for 30 min. Under the same conditions as above, the supernatant was
applied to GC-MS to afford D-fucose [tR 4.57 min, [R]2D5 +66.4 (c 0.8,
H2O)] and L-rhamnose [tR 5.09 min, [R]2D5 -9.7 (c 1.0, H2O)], by
comparison with authentic samples.
5
3.79, q (6.4)
1.49, d (6.4)
6.31, d (1.5)
5.29, br s
5.60, dd (3.3, 10.0)
3.79, q (6.5)
1.49, d (6.4)
6.31, d (1.5)
5.29, brs
5.62, dd (3.0, 10.0)
3.78, q (6.2)
1.49, d (6.2)
6.32, br s
5.29, br s
5.62 *
6
Rha-1
2
3
4
4.61, dd (10.0, 10.0) 4.66, dd (10.0, 10.0) 4.62,dd (10.0, 10.0)
5
6
5.00, dd (10.0, 6.3)
1.56, d (6.3)
5.58, br s
5.01, dd (10.0, 6.3)
1.57, d (6.3)
5.60, br s
5.00, dd (10.0, 6.0)
1.54, d (6.0)
5.59, br s
Rha′-1
2
3
4
5
6
Rha′′-1
2
3
4
5
6
Rha′′′-1
2
3
4
5
6
Ag-2
5.79, br s
5.79, br s
5.80, br s
4.57, dd (3.0, 9.5)
4.24, dd (9.5, 9.5)
4.34, dd (9.5, 6.3)
1.54, d (6.3)
5.83, br s
4.59, dd (3.0, 9.5)
4.24, dd (9.5, 9.5)
4.36, dd (9.5, 6.2)
1.58, d (6.2)
5.90, brs
4.87, brs
5.82, dd (3.0, 10.0)
6.01, dd (10.0, 10.0) 4.23, dd (10.0, 10.0)
4.45, dd (10.0, 6.3)
1.39, d (6.3)
5.63, br s
4.74, dd (1.8, 3.4)
4.40, dd (3.4, 9.5)
4.18, dd (9.5, 9.5)
4.25, dd (9.5, 6.1)
1.69, d (6.1)
2.25, ddd (4.2, 7.0,
15.0)
2.86, ddd (4.2, 7.0,
15.0)
3.86, m
4.64, dd (3.0, 9.6)
4.24 *
4.34 *
1.55, d (6.0)
5.86, br s
6.06, br s
11-(R-MPA)-hydroxyhexadecanoic acid methyl ester (12): color-
less oil (CHCl3), [R]2D5 -2.0 (c 0.10, CHCl3); IR νmax (KBr) 3442, 2927,
6.04, br s
2855, 1743, 1261, 802 cm-1 1H NMR (600 MHz, CDCl3) δH 7.44
;
5.81, dd (3.0, 10.0)
4.26, dd 10.0, 10.0)
4.41, dd (10.0, 6.3)
1.69, d (6.3)
5.58, br s
5.85 *
(m, 2, C6H2), 7.34 (m, 3, C6H3), 4.90 (m, 1, OCH-11), 4.73 (s, 1, OCH),
3.67 (s, 3, OCH3), 3.41 (s, 3, OCH3), 2.30 (t, 2, J ) 7.4 Hz, OCOCH2-
2), 1.67 (m, 2, CH2-10), 1.41 (m, 2, CH2-12), 0.77 (t, 3, J ) 7.1 Hz,
CH3-16); ESIMS m/z 457 [M + Na]+; 435 [M + H]+.
4.43, dd (10.0, 6.0)
1.68, d (6.0)
5.58, br s
4.73, br s
4.30 *
4.17 *
4.25 *
1.70, d (6.2)
2.41, m
4.72, br s
4.30 *
11-(S-MPA)-hdroxyhexadecanoic acid methyl ester (13): colorless
oil (CHCl3), [R]2D5 +1.4 (c 0.20, CHCl3); IR νmax (KBr) 3453, 2961,
4.18, dd (9.5, 9.5)
4.25, dd (9.5, 6.1)
1.69, d (6.1)
2.23, ddd (4.3, 7.1,
15.5)
2.88, ddd (4.3, 7.1,
15.5)
3.87, m
1
2926, 2852, 1742, 1261 cm-1; H NMR (600 MHz, CDCl3) δH 7.44
(m, 2, C6H2), 7.34 (m, 3, C6H3), 4.90 (m, 1, OCH-11), 4.73 (s, 1, OCH),
3.67 (s, 3, OCH3), 3.41 (s, 3, OCH3), 2.30 (t, 2, J ) 7.6 Hz, OCOCH2-
2), 1.61 (m, 2, CH2-10), 1.54 (m, 2, CH2-12), 0.84 (t, 3, J ) 7.1 Hz,
CH3-16); ESIMS m/z 457 [M + Na]+.
Bioassay. The assay of cytotoxic activity against laryngeal carcinoma
(Hep-2) cells of compounds 1–9 was performed according to the
published method (4).
2.25, m
11
16
Cna-2
3
Iba-2
3.85, m
0.88, t (6.8)
0.87, t (7.2)
0.84, t (7.2)
6.82, d (15.9)
7.91, d (15.9)
6.82, d (15.9)
7.90, d (15.9)
2.54, m
6.50, d (15.9)
7.80, d (15.9)
2.60, m
RESULTS AND DISCUSSION
3
3′
Mba-2
2-CH3
4
Dodeca-2
12
Ba-2
4
1.13, d (7.0)
1.14, d (7.0)
2.38, t q (7.0, 7.0)
1.07, d (7.0)
0.99, t (7.4)
1.17, d (7.2)
1.17, d (7.2)
Structure Elucidation of Seven Resin Glycosides Com-
pounds. The 95% EtOH extract of the dried tubers of I. batatas
was partitioned between CHCl3 and water to provide a jalapin-
like fraction. To examine the presence of resin glycosides, the
fraction was subjected to alkaline and acid hydrolysis, succes-
sively. GC-MS analysis of the ether-soluble fraction of the
alkaline hydrolysis products demonstrated the presence of six
peaks identified as acetic acid, n-butyric acid, isobutyric acid,
(S)-2-methylbutyric acid, n-dedocanoic acid, and trans-cinnamic
acid by comparison of their mass spectra, retention times, and
optical rotations with those of authentic samples (7). The alkaline
hydrolysis of the ether-insoluble fraction gave simonic acid B
(10) (8), which has also been obtained previously from I. batatas
(cv. Simon). The lactone linkages of compounds 1-3 were all
at C-3 of rhamnose (Rha); the difference was the substituents
in Rha′ and Rha′′, whereas by comparison with 1–3, the lactone
linkages of compounds 4–7 were at C-2 of the Rha unit and
the difference was also the substituents in Rha′ and Rha′′, which
were the structural characteristics of these compounds.
2.34, t q (7.0, 7.0)
1.12, d (6.5)
0.87, t (7.4)
2.88, t (7.0)
1.01, t (7.0)
1.10, t (7.0)
0.96, t (6.9)
a Chemical shifts (δ) are in ppm relative to TMS. The spin coupling (J) is given
in parentheses (Hz). Chemical shifts marked with an asterisk (*) indicate overlapped
signals. Spin-coupled patterns are designated as follows: s, singlet; br s, broad
singlet; d, doublet; t, triplet; m, multiplet; q, quartet. All assignments are based on
1H- H TOCSY experiments. b Abbreviations: Fuc, fucose; Rha, rhamnose; Ag,
11-hydroxyhexadecanoyl; Iba, isobutanoyl; Mba, (S)-2-methylbutanoyl; Cna, trans-
1
cinnamoyl; Dodeca, n-dodecanoyl; Ba, n-butanoyl.
(1.1 mg) of the alkaline hydrolysis of 5 was purified by RP-C18
chromatography, eluted with MeOH/H2O (25:75), to give 2-methyl-
butyric acid (0.3 mg). This was proved to be in the S configuration by
comparing the optical rotation ([R]2D5 + 19.0) with that of authentic
(S)-2-methylbutyric acid.
Acid Hydrolysis. The ether-insoluble layer from the alkaline
hydrolysis of 5 was extracted with n-BuOH (30.0 mL) to afford
10 (9, 10), which was methylated with diazomethane. The methylation
product was hydrolyzed by 1 N H2SO4 and then extracted with ether
(30.0 mL) to yield 11 (11-hydroxyhexadecanoic acid methyl ester,
12%). A solution of (R)-methoxyphenylacetic acid (12.0 mg, MPA)
and 4-dimethylaminopyridine (10.0 mg, DMAP) in CH2Cl2 (1.0 mL)
was added to CH2Cl2 (1.5 mL) containing 11 (2.0 mg), followed by
N,N-dicyclohexylcarbodiimide (10.0 mg, DCC). The mixture was stirred
for 17.0 h at 25.0 °C. EtOAc (30.0 mL) was added to quench the
Batatoside A (1), an amorphous white powder, gave a quasi-
molecular ion at m/z 1267.6425 [M - H]- (C64H99O25) in the
negative-ion HRESIMS. Alkaline hydrolysis with 5% KOH
afforded an organic acid mixture. The organic acids were
identified as isobutyric acid (Iba), (S)-2-methylbutyric acid
(Mba), and trans-cinnamic acid (Cna), respectively, by GC-
MS and optical rotation, when compared with authentic samples.
1
The H NMR spectrum of 1 showed a pair of trans-coupled
olefinic protons at δH 6.82 (d, J ) 15.9 Hz, H-2 of Cna) and
7.90 (d, J ) 15.9 Hz, H-3 of Cna), and 7.27–7.45 (m, C6H5)

2366 J. Agric. Food Chem., Vol. 56, No. 7, 2008
Yin et al.
Table 3. 1H NMR Data of Compounds 4-7 (C5D5N, 600 MHz)a
protonb
4
5
6
7
Fuc-1
2
3
4
5
6
Rha-1
2
3
4
4.75, d (7.5)
4.75, d (7.5)
4.16, dd (7.5, 9.4)
4.08, dd (9.4, 3.5)
3.98, d (3.5)
3.77, q (6.4)
1.50, d (6.4)
5.47, br s
4.75, d (7.4)
4.18, dd (7.4, 9.4)
4.11, dd (9.4, 3.5)
3.98, d (3.5)
3.77, q (6.4)
1.50, d (6.4)
5.48, br s
4.76, d (7.4)
4.16, dd (7.5, 9.4)
4.08, dd (9.4, 3.5)
3.98, d (3.5)
3.77, q (6.4)
1.50, d (6.4)
5.48, br s
5.98, br s
5.02, dd (3.3, 9.5)
4.20, dd (9.5, 9.5)
4.27, dd (9.5, 6.2)
1.61, d (6.2)
4.18, dd (7.4, 9.4)
4.11, dd (9.4, 3.0)
3.99, d (3.0)
3.78, q (6.9)
1.50, d (6.4)
5.50, d (2.0)
5.97, dd (2.0, 3.2)
5.03, dd (3.2, 9.4)
4.23, dd (9.4, 9.4)
4.27, dd (9.4, 6.3)
1.64, d (6.3)
5.91, br s
5.97, br s
5.01, dd (3.2, 9.5)
4.21, dd (9.5, 9.5)
4.44, dd (9.5, 6.1)
1.62, d (6.1)
6.11, br s
5.05, dd (3.2, 9.5)
4.22, dd (9.5, 9.5)
4.27, dd (9.5, 6.0)
1.60, d (6.0)
6.03, br s
5
6
Rha′-1
2
6.05, br s
5.96, br s
6.11, d (1.8)
6.04, br s
5.99, br s
6.01, br s
3
4
5
6
4.68, dd (3.0, 10.0)
4.29, dd (10.0, 10.0)
4.37, dd (10.0, 6.2)
1.65, d (6.2)
5.96, br s
4.97, br s
4.65, dd (3.0, 9.1)
4.32, dd (9.1, 9.3)
4.37, dd (9.3, 5.9)
1.67, d (5.9)
5.94, br s
4.61, dd (3.0, 9.0)
4.34, dd (9.0, 9.0)
4.44, dd (9.0, 5.7)
1.55, d (5.7)
5.89, br s
4.67, dd (3.0, 8.9)
4.37, dd (8.9, 8.9)
4.30, dd (8.9, 6.3)
1.66, d (6.3)
5.99, br s
4.98, br s
Rha′′-1
2
5.98, br s
6.15, br s
3
4
5
6
5.91, dd (3.3, 10.0)
6.09, dd (10.0, 10.0)
4.45, dd (10.0, 6.2)
1.45, d (6.2)
5.67, br s
4.78, br s
4.41, dd (3.0, 9.3)
4.29, dd (9.3,9.3)
4.50, dd (9.3,6.0)
1.54, d (6.0)
2.37, ddd (4.2,7.0,15.0)
2.22, ddd (4.2,7.0,15.0)
3.87, m
4.68, dd (3.0, 9.3)
5.78, dd (9.3, 9.3)
4.37, dd (9.3, 6.2)
1.65, d (6.2)
5.67, br s
5.92, dd (3.4, 9.3)
4.21, dd (9.3, 9.3)
4.47, dd (9.3, 6.0)
1.58, d (6.0)
5.57, br s
4.71, br s
4.30 *
4.17 *
4.25 *
5.93, dd (3.0, 10.0)
6.06, dd (10.0, 10.0)
4.48, dd (10.0, 6.1)
1.60, d (6.1)
5.65, d (1.0)
4.79, br s
4.48 *
4.21 *
4.48 *
1.51, d (6.4)
2.27, ddd (4.3,7.0,15.0)
2.43, ddd (4.3,7.0,15.0)
3.88, m
0.85, t (7.2)
6.55, d (15.9)
7.82, d (15.9)
Rha′′′-1
2
3
4
5
6
Ag-2
4.78, br s
4.39, dd (3.3, 9.0)
4.19, dd (9.0, 9.0)
4.26, dd (9.0, 6.0)
1.54, d (6.0)
1.91, m
2.23, m
3.85, m
0.87, t (7.0)
6.54, d (15.9)
7.80, d (15.9)
2.34, m
1.09, d (7.1)
0.85, t (7.3)
2.47, m
1.70, d (6.2)
2.23 *
2.37 *
11
16
Cna-2
3
Mba-2
2-CH3
4
Dodeca-2
12
Aa-2
3.86, m
0.84, t (7.5)
0.83, t (7.3)
6.81, d (16.0)
7.90, d (16.0)
2.37 *
1.07, d (7.0)
0.84, t (7.4)
2.43 *
6.56, d (15.9)
7.82, d (15.9)
2.36, m
1.06, d (7.0)
0.86, t (7.0)
2.47, t (7.3)
0.87, t (6.8)
2.64, t (7.0)
0.88, t (7.2)
1.12
0.87, t (6.8)
0.85, t (7.2)
a Chemical shifts (δ) are in ppm relative to TMS. The spin coupling (J) is given in parentheses (Hz). Chemical shifts marked with an asterisk (*) indicate overlapped
1
1
signals. Spin-coupled patterns are designated as follows: s, singlet; br s, broad singlet; d, doublet; t, triplet; m, multiplet; q, quartet. All assignments are based on H- H
TOCSY experiments. b Abbreviations: Fuc, fucose; Rha, rhamnose; Ag, 11-hydroxyhexadecanoyl; Aa, acetonoyl; Mba, (S)-2-methylbutanoyl; Cna, trans-cinnamoyl; Dodeca,
n-dodecanoyl.
due to five phenyl protons, indicating the presence of a
3-phenylprop-2-enoyl (Cna) moiety. The methyl protons at δH
1.13 (d, J ) 7.0 Hz, CH3-3 of Iba) and 1.14 (d, J ) 7.0 Hz,
CH3′-3 of Iba) showed HMBC correlations with the carbon
signals at δC 176.5 (C-1 of Iba) and 34.4 (C-2-Iba), suggesting
the presence of an isobutyryl moiety. The protons at δH 0.99 (t,
J ) 7.4 Hz, H-4 of Mba), 1.07 (d, J ) 7.0 Hz, CH3′-2 of Mba),
and 2.38 (tq, J ) 7.0 and 7.0 Hz, H-2 of Mba) displayed in one
spin system from the TOCSY spectrum, consistent with the
occurrence of an (S)-2-methylbutyryl moiety.
Diagnostic signals of the aglycone of 1 were the methyl triplet
at δH 0.88 (t, J ) 6.8 Hz, H-16 of aglycone), the methylenes at
δH 2.23 (ddd, J ) 4.3, 7.1 and 15.5 Hz, H-2a of aglycone) and
2.88 (ddd, J ) 4.3, 7.1, and 15.5 Hz, H-2b of aglycone), and
the oxygenated methane at δH3.87 (m, H-11 of aglycone). Three
substituents were identified in the NMR spectra to be the same as
those from the analysis results of GC-MS. The lactone position at
C-3 of rhamnose was proved by cross-peak in the HMBC spectrum.
The acylation pattern of 1 was anchored by HMBC correlations
from the proton of sugar junction resonances to the carbonyl of
three substituents. The H-2 of rhamnose′ (δH 5.79) showed HMBC
cross-peaks with resonances at δC 175.4 ([C-1-(S)-2-methylbu-
tanoyl]), and an HMBC correlation was observed from the H-2 of
rhamnose′′ (δH 6.04) and H-3 of rhamnose′′ (δH 5.81) to δC 166.5
(C-1 of trans-cinnamoyl) and δC 176.5 (C-1 of isobutanoyl),
respectively (Figure 1). The assignments of the carbon and
proton signals were based on TOCSY, HMQC, and HMBC
spectra, which are listed in Tables 1 (13C NMR) and 2 (1H
NMR). The structure of 1 was finally established as
(S)-jalapinolic acid 11-O-R-L-rhamnopyranosyl-(1f3)-O-[2-O-
trans-cinnamoyl-3-O-isobutanoyl-R-L-rhamnopyranosyl-(1f4)]-
O-[2-O-(S)-2-methylbutyryl]-R-L-rhamnopyranosyl-(1f4)-O-R-
L-rhamnopyranosyl-(1f2)-O-ꢀ-D-fucopyranoside, intramolecular
1,3′′-ester.
Batatoside B (2) was obtained as an amorphous white powder.
Compound 2 showed a quasi-molecular ion at m/z 1253.5944
[M - H]- (C63H97O25) in the negative-ion HRESIMS. The
difference of 14 mass units observed in the mass spectra of
compounds 1 and 2 indicated there is a CH2 different between
them. GC-MS analysis of the alkaline hydrolysis mixture of 2
showed the presence of cinnamic acid, isobutyric acid, and
n-butyric acid, and the aqueous layer afforded simonic acid B.
The linkage sites of the three substituent groups and the lactone
site were determined by the correlations in HMBC spectrum.

Pentasaccharide Glycosides from Sweet Potato
J. Agric. Food Chem., Vol. 56, No. 7, 2008 2367
Figure 2. Key HMBC correlations from H to C for compound 4.
R-L-rhamnopyranosyl-(1f4)-O-R-L-rhamnopyranosyl-(1f2)-O-
ꢀ-D-fucopyranoside, intramolecular 1,3′′-ester.
Batatoside C (3) was obtained as an amorphous white powder
and displayed a quasi-molecular ion peak [M + Cl]- at m/z
1415.7580 in the negative HRESIMS, consistent with a mo-
1
lecular formula of C72H116O25. Some of the 13C and H NMR
signals of 3 were similar to those of 1 (Tables 1 and 2). For
this reason, the acylation sites of 3 were assumed to be the same
as those of 1, which were supported by the following HMBC
cross-peaks: δH 5.62 (H-3 of rhamnose) with δC 173.3 (C-1 of
aglycon); δH 5.80 (H-2 of rhamnose′′) with δC 175.4 ([C-1 of
(S)-2-methylbutanyol]); and δH 6.06 (H-2 of rhamnose′′) and
5.85 (H-3 of rhamnose′′) with δC 166.6 (C-1 of trans-cinnamoyl)
and 174.8 (C-1 of n-dedocanoyl), respectively. The assignments
1
of the 13C and H NMR signals were determined according to
the corrolations in TOCSY, HMQC, and HMBC spectra (Tables
1 and 2). On the basis of the above results, the structure of 3
was confirmed as (S)-jalapinolic acid 11-O-R-L-rhamnopyra-
nosyl-(1f3)-O-[2-O-trans-cinnamoyl-3-O-n-dedocanoyl-R-L-
rhamnopyranosyl-(1f4)]-O-[2-O-(S)-2-methylbutyryl]-R-L-rham-
nopyranosyl-(1f4)-O-R-L-rhamnopyranosyl-(1f2)-O-ꢀ-D-
fucopyranoside, intramolecular 1,3′′-ester.
Batatoside D (4), batatoside E (5), and batatoside F (6) were
also obtained as amorphous white powders. The molecular
formulas of 4–6 were all C72H116ClO25, according to the quasi-
molecular ion peaks [M + Cl]- at m/z 1415.7487, 1415.7584,
and 1415.7305 in their respective negative HRESIMS. Alkaline
hydrolysis of compounds 4-6 afforded the same organic acids
as those of 3. The lactone linkages to the positions of C-2 in
the rhamnoses, which showed a major difference between 4-6
and 3, have been proved by the correlations in their HMBC
spectrum. Accordingly, Ccompounds 4-6 and 3 could be
thought to be regioisomers.
The substituents as well as their positions and lactone linkage
of 4-6 were determined by HMBC spectrum. A HMBC
correlation of 4 (Figure 2) was observed from δH 5.98 (H-2 of
rhamnose) to δC 173.1 (C-1 of the aglycon). The H-2 signal of
rhamnose′ (δH 5.96) showed a cross-peak with δC 175.4 ([C-1
of (S)-2-methylbutanoyl]). H-3 of rhamnose′′ (δH 5.91) and H-4
of rhamnose′′ (δH 6.09) displayed HMBC correlations with δC
166.4 (C-1 of trans-cinnamoyl) and δC 173.2 (C-1 of n-
dedocanoyl). The unambiguous assignments of signals were
achieved from the TOCSY, HMQC, and HMBC spectra (Tables
1 and 3). The structure of 4 was established as (S)-jalapinolic
acid 11-O-R-L-rhamnopyranosyl-(1f3)-O-[3-O-trans-cinnamoyl-
4-O-n-dedocanoyl-R-L-rhamnopyranosyl-(1f4)]-O-[2-O-(S)-2-
methylbutyryl]-R-L-rhamnopyranosyl-(1f4)-O-R-L-rhamnopy-
ranosyl-(1f2)-O-ꢀ-D-fucopyranoside, intramolecular 1,2′′-ester.
Figure 1. Key HMBC correlations from H to C for compound 1.
The H-3 signal of rhamnose displayed a HMBC correlation to
a carbonyl at δC 174.8 (C-1 of aglycon), whereas the H-2
resonance of rhamnose′ showed a HMBC correlation to the
carbonyl at δC 176.0 [C-1 of (S)-2-methylbutanoyl]. Two cross-
peaks have also been observed between protons of H-3 and H-4
of rhamnose′′ (δH 5.82 and 6.01) and the carbon atoms of δC
166.2 (C-1 of trans-cinnamoyl) and 176.3 (C-1 of isobutanoyl),
respectively. The structure of 2 was identified as (S)-jalapinolic
acid 11-O-R-L-rhamnopyranosyl-(1f3)-O-[3-O-trans-cinnamoyl-
4-O-isobutanoyl-R-L-rhamnopyranosyl-(1f4)]-O-(2-O-butanoyl)-

2368 J. Agric. Food Chem., Vol. 56, No. 7, 2008
Yin et al.
The linkage sites of 5 were also determined by HMBC
correlations, in which H-2 of rhamnose (δH 5.91) showed a
correlation to the carbon atom in the carbonyl group at δC 173.1
(C-1 of aglycon), and a correlation was observed from H-2 of
rhamnose′ (δH 5.99) to δC 175.4 (C-1 of (S)-2-methylbutanoyl).
The protons of H-2 of rhamnose′′ (δH 5.98) and H-4 of
rhamnose′′ (δH 5.78) displayed cross-peaks with δC 166.8 (C-1
of trans-cinnamoyl) and δC 173.5 (C-1 of dodecanoyl), respec-
tively. The structure of 5 was concluded as (S)-jalapinolic acid
11-O-R-L-rhamnopyranosyl-(1f3)-O-[2-O-trans-cinnamoyl-4-
O-n-dedocanoyl-R-L-rhamnopyranosyl-(1f4)]-O-[2-O-(S)-2-
methylbutyryl]-R-L-rhamnopyranosyl-(1f4)-O-R-L-rhamnopy-
ranosyl-(1f2)-O-ꢀ-D-fucopyranoside, intramolecular 1,2′′-ester.
The linkage positions of three constituents groups and lactone
site of 6 were also determined from the HMBC spectrum, in
which proton H-2 of rhamnose (δH 5.97) showed a cross-peak
with δC 173.1 (C-1 of aglycon), and H-2 of rhamnose′ displayed
a correlation to a carbonyl at δC 175.4 ([C-1 of (S)-2-
methylbutanoyl]). In addition, the protons at δH 6.15 (H-2 of
rhamnose′′) and 5.92 (H-3 of rhamnose′′) correlated with δC
166.6 (C-1 of trans-cinnamoyl) and 173.6 (C-1 of dodecanoyl)
in the HMBC spectrum, respectively. The structure of 6 was
elucidated as (S)-jalapinolic acid 11-O-R-L-rhamnopyranosyl-
(1f3)-O-[2-O-trans-cinnamoyl-3-O-dodecanoyl-R-L-rhamnopy-
ranosyl-(1f4)]-[2-O-(S)-2-methylbutyryl]-R-L-rhamnopyranosyl-
(1f4)-O-R-L-rhamnopyranosyl-(1f2)-O-ꢀ-D-fucopyranoside,
intramolecular 1,2′′-ester.
Batatoside G (7) was obtained as an amorphous white powder.
The molecular formula of 7 was C69H110O25 according to quasi-
molecular ion peaks [M + Cl]- at m/z 1373.6898 in the negative
HRESIMS. The alkaline hydrolysis of 7 afforded n-dedocanoic
acid, acetic acid, and trans-cinnamic acid, by comparison with
authentic samples proved by GC-MS. The aqueous layer
afforded simonic acid B. The linkage sites of three constituents
groups and lactone site were determined by the following
HMBC correlations. An HMBC correlation was observed from
the H-2 of rhamnose (δH 5.03) to δC 173.1 (C-1 of aglycon).
H-2 of rhamnose′ (δH 6.04) displayed a HMBC correlation to
δC 172.9 (C-1 of dodecanoyl). H-3 (δH 5.93) and H-4 (δH 6.06)
of rhamnose′′ showed HMBC cross-peaks with δC 166.4 (C-1
of trans-cinnamoyl) and 176.4 (C-1 of acetyl), respectively.
Accordingly, the structure of 7 was concluded to be
(S)-jalapinolic acid 11-O-R-L-rhamnopyranosyl-(1f3)-O-[3-O-
trans-cinnamoyl-4-O-acetanoyl-R-L-rhamnopyranosyl-(1f4)]-
(2-O-n-dedocanoyl]-R-L-rhamnopyranosyl-(1f4)-O-R-L-rham-
nopyranosyl-(1f2)-O-ꢀ-D-fucopyranoside, intramolecular 1,2′′-
ester.
(1–7). This material is available free of charge via the Internet
at http://pubs.acs.org.
LITERATURE CITED
(1) The Editorial Committee of the Administration Bureau of Flora
of China. Flora of China (Zhongguo Zhiwuzhi); Beijing Science
and Technology Press: Beijing, China, 2005; Vol. 64, pp 88–90.
(2) Noda, N.; Ono, M.; Miyahara, K.; Kawasaki, T. Resin glycosides.
I. Isolation and structure elucidation of orizabin-I, II, III and IV,
genuine resin glycosides from the root of Ipomoea orizabensis.
Tetrahedron 1987, 43, 3889–3902.
(3) Pereda-Miranda, R.; Fragoso-Serrano, M.; Escalante-Sánchez, E.;
Hernández-Carlos, B.; Linares, E.; Bye, R. Profiling of the resin
glycoside content of Mexican jalap roots with purgative activity.
J. Nat. Prod. 2006, 69, 1460–1466.
(4) Pereda-Miranda, R.; Kaatz, G. W.; Gibbons, S. Polyacylated
oligosaccharides from medicinal mexican morning glory species
as antibacterials and inhibitors of multidrug resistance in Staphy-
lococcus aureus. J. Nat. Prod. 2006, 69, 406–409.
(5) Chérigo, L.; Pereda-Miranda, R. Resin glycosides from the flowers
of Ipomoea murucoides. J. Nat. Prod. 2006, 69, 595–599.
(6) Li, S. Z. Min Dynasty. Compendium of Materia Medica; Pepole’s
Medical Publishing House: Beijing, China, 1999; pp1501.
(7) Escalante-Sánchez, E.; Pereda-Miranda, R. Batatins I and II, ester-
type dimers of acylated pentasaccharides from the resin glycosides
of sweet potato. J. Nat. Prod. 2007, 70, 1029–1034.
(8) Noda, N.; Yoda, S.; Kawasaki, T.; Miyahara, K. Resin. XV.1)
simonins I-IV, ether-soluble resin glycosides (jalapins) from the
roots of Ipomoea batatas (cv. Simon). Chem. Pharm. Bull. 1992,
40, 3163–3168.
(9) Noda, N.; Takahashi, N.; Kawasaki, T.; Miyahara, K.; Yang, C. R.
Stoloniferins I-VII, resin glycosides from Ipomoea stoloniferins.
Phytochemistry 1994, 36, 365–371.
(10) Pereda-Miranda, R.; Escalante-Snchez, E.; Escobedo-Martnez, C.
Characterization of lipophilic pentasaccharides from beach morn-
ing glory (Ipomoea Pes-caprae). J. Nat. Prod. 2005, 68, 226–
230.
(11) Enriquen, R. G.; Leon, I.; Perez, F.; Walls, F.; Carpenter, K.;
Puzzuoli, F. V.; Reynolds, W. F. Characterization by two-
dimensional NMR spectrocopy, of a complex tetrasaccharide
glycoside isolated from Ipomoea stan. Can. J. Chem. 1992, 70,
1000–1008.
(12) Seco, J. M.; Quinoá, E.; Riguera, R. The assignment of absolute
configuration by NMR. Chem. ReV. 2004, 14, 17–117.
(13) Ono, M.; Yamada, F.; Noda, N.; Kawadaki, T.; Miyahara, K. Resin
glycosides. XVIII.1) determination by Mosher’s Method of the
absolute configurations of mono- and dihydroxyfatty acids
originated from resin glycosides. Chem. Pharm. Bull. 1993, 41,
1023–1026.
(14) Ono, M.; Kubo, K.; Miyahara, K.; Kawasaki, T. Operculin I and
II. New ether-soluble resin glycosides (“jalapin”) with fatty acid
ester groups from rhizome jalapae braziliensis (root of Ipomoea
operculata). Chem. Pharm. Bull. 1989, 37, 241–244.
Cytotoxic Activity Assay. The assay of cytotoxic activity
against laryngeal carcinoma (Hep-2) cells of compounds 1–9
was performed according to the published method (4). The
results indicated that compound 5 showed weak cytotoxic
activities against Hep-2 cells; its ED50 value was 6 µg/mL. The
ED50 values of other compounds were >40 µg/mL, which could
be thought to be inactive, whereas that of the positive drug
control, vinblastine, was 0.002 µg/mL.
(15) Cao, S. G.; Guza, R. C.; Wisse, G. J.; Miller, J. S.; Evans, R.;
Kingston, D. G. I. Ipomoeassins A-E, cytotoxic macrocyclic
glycoresind from the leaves of Ipomoea squmosa from the
suniname rainforest. J. Nat. Prod. 2005, 68, 487–492.
Received for review November 15, 2007. Revised manuscript received
January 29, 2008. Accepted January 31, 2008. This research was
supported by the National Natural Science Foundation of China (No.
30472144), the Cultivation Fund of the Key Scientific and Technical
Innovation Project, Ministry of Education of China (707033), and the
Natural Science Foundation of the Jiangsu Higher Education Institu-
tions of China (No. 06KJD360100).
ACKNOWLEDGMENT
We acknowledge Dr. Bing Ma, Shandong University, for
measuring the TOCSY, HMQC, and HMBC NMR spectra.
Supporting Information Available: Spectra (HRESIMS, 1H,
13C NMR, TOCSY, HMQC, HMBC) of batanosides A-G
JF0733463