An iridoid glucoside from Jasminum hemsleyi

Article abstract of DOI:10.1021/np960189l

A new iridoid glucoside, jashemsloside E, was isolated from the leaves of Jasminum hemsleyi. Its structure was elucidated on the basis of chemical and spectral data.

Full text of DOI:10.1021/np960189l

798
J . Nat. Prod. 1996, 59, 798-800
An Ir id oid Glu cosid e fr om J a sm in u m h em sleyi
Takao Tanahashi,* Atsuko Shimada, Mayumi Kai, Naotaka Nagakura, Kenichiro Inoue,† and
Cheng-Chang Chen‡
Kobe Pharmaceutical University, Higashinada-ku, Kobe 658, J apan, Gifu Pharmaceutical University, Mitahora-higashi,
Gifu 502, J apan, and National Kaoshiung Normal University, Kaoshiung, Taiwan, Republic of China
Received J anuary 12, 1996X
A new iridoid glucoside, jashemsloside E, was isolated from the leaves of J asminum hemsleyi.
Its structure was elucidated on the basis of chemical and spectral data.
We have previously reported the isolation of six new
iridoid glucosides, jashemslosides A, B, C (1), and D (2),
6′-O-trans-p-coumaroylloganin, and 6′-O-cis-p-couma-
roylloganin from the leaves of J asminum hemsleyi
Yamamoto (Oleaceae), which grows in Taiwan.1 In a
continuation of this study, we have examined this
species further and isolated an additional minor iridoid
glucoside. This paper reports the structure elucidation
of this new compound (3).
solve this problem, compound 3 was subjected to metha-
nolysis with NaOMe, giving loganin (4) and a mono-
terpene glycoside (6). The H-NMR and SIMS spectra
of 6 demonstrated that an apiosyl group as well as a
glucose unit were attached to a menthiafolic acid methyl
ester skeleton. Accordingly, the structure of jashemslo-
side E was established as (6′′S)-7-O-{6-O-[â-D-apiofuran-
osyl-(1f6)-â-D-glucopyranosyl]menthiafolioyl}loganin (3)
(Chart 1).
1
The novel glucoside 3, named jashemsloside E, was
obtained as an amorphous powder. HRSIMS estab-
lished a molecular formula for 3 of C38H58O21. The
compound showed a UV maximum at 224 nm and IR
Exp er im en ta l Section
Gen er a l Exp er im en ta l P r oced u r es. The UV spec-
trum was recorded on a Shimadzu UV-240 spectropho-
tometer and the IR spectrum on a Shimadzu FTIR-8200
infrared spectrophotometer. The optical rotation was
measured on a J asco DIP-370 digital polarimeter. SIMS
and HRSIMS were obtained with a Hitachi M-4100
mass spectrometer, with glycerol or 3-NOBA as the
matrix. The NMR experiments were performed with a
Varian VXR-500 spectrometer, with Me4Si as internal
standard. HPLC was performed using a Waters system
(600E Multisolvent Delivery System, 486 Tunable Ab-
sorbance Detector). Column chromatography was car-
ried out with Si gel 60 (70-230 mesh, Nacalai Tesque,
Kyoto, J apan). TLC was performed on precoated Kie-
selgel 60F254 plates (Merck), and spots were visualized
under UV light.
bands at 3439, 1716, 1705, 1699, 1647, and 1636 cm-1
.
1
Its H- and 13C-NMR spectra gave characteristic signals
corresponding to loganin (4), a menthiafolic acid [5, (2E)-
6-hydroxy-2,6-dimethyl-2,7-octadienoic acid] moiety, and
a glucose unit, indicating the structural similarity of 3
to jashemsloside C (1) and jashemsloside D (2).1 Fur-
thermore, its 1H-NMR spectrum showed two coupled
doublets at δ 4.97 and 3.87 (J ) 2.5 Hz), an AB system
at δ 3.76 and 3.96 (J ) 9.5 Hz), and a two-proton singlet
at δ 3.58, suggesting the presence of an apiose unit in
the molecule. Conventional acetylation of 3 with Ac2O-
pyridine gave the nonaacetate 3a and the decaacetate
3b, confirming an apiose unit with a tertiary hydroxyl
group.2 The anomeric configuration of apiose in 3 was
determined to be â from the coupling constant (d, J )
2.5 Hz) of the anomeric proton and from the 13C-NMR
chemical shifts of C-1′′′′, C-2′′′′, and C-3′′′′ of the apiose
moiety.3,4
P la n t Ma ter ia l. The plant material used was pub-
lished previously.1
Extr a ction a n d Isola tion . Solvent extraction was
carried out as reported previously.1 Fraction V (2.38
g) was chromatographed on a Si gel column. Elution
with EtOAc-C6H6-EtOH mixtures as eluents, with the
EtOH content indicated in EtOAc-C6H6 (4:1) gave five
fractions, V/1 (5-7%, 842 mg), V/2 (7-15%, 559 mg),
V/3 (15%, 254 mg), V/4 (15-20%, 97.5 mg), and V/5 (20-
50%, 230 mg). Fraction V/2 was purified by preparative
HPLC (µBondasphere, 5 µM, C18 -100 Å, MeOH-H2O,
1:1), affording 1 (50.9 mg) and 2 (43.6 mg) as briefly
described.1 Fractions V/3, V/4, and V/5 were separately
purified by preparative HPLC (MeOH-H2O, 1:1) to give
3 (10.3 mg, 8.1 mg, and 7.3 mg, respectively).
1
Detailed comparison of the H- and 13C-NMR data of
1-3 showed that the chemical shifts of proton signals
for H-7′′, H2-8′′, and H3-10′′, as well as the chemical
shifts of carbon signals for C-5′′, C-8′′, and C-10′′ of 3,
were in good accord with those of 1 [δ 41.2 (C-5′′), δ
116.1 (C-8′′), δ 23.6 (C-10′′)] but differed from those of
2 [δ 39.9 (C-5′′), δ 115.3 (C-8′′), δ 24.0 (C-10′′)].1 These
results indicated the absolute configuration of C-6′′ of
the menthiafolic acid moiety in 3 to be S, as is the case
for 1.5
A remaining point of ambiguity was the site of linkage
of the apiose moiety. Glycosylation shifts were observed
for C-6′ or C-6′′′ (+6.0 ppm) and C-5′ or C-5′′′ (-1.1
ppm), when compared with the 13C-NMR data of 1.2
However, it was rather difficult to differentiate between
C-6′ and C-6′′′ by spectroscopic methods. In order to
J a sh em slosid e E (3): amorphous powder; [R]20
D
-42.2° (c 1.01, MeOH); UV (MeOH) λ max (log ꢀ) 224
(4.29) nm; IR (KBr) ν max 3439, 1716, 1705, 1699, 1647,
1636 cm-1; 1H NMR (CD3OD) δ 1.07 (3H, d, J ) 6.5 Hz,
H3-10), 1.40 (3H, s, H3-10′′), 1.72 (2H, m, H2-5′′), 1.76
(1H, ddd, J ) 14.5, 8.0, 5.0 Hz, H-6), 1.83 (3H, d, J )
1.0 Hz, H3-9′′), 2.10 (1H, td, J ) 9.0, 4.5 Hz, H-9), 2.15
(1H, m, H-8), 2.28 (1H, ddd, J ) 14.5, 8.0, 1.5 Hz, H-6),
2.32 (2H, m, H2-4′′), 3.11 (1H, br q, J ) 8.0 Hz, H-5),
* To whom correspondence should be addressed. Phone: 81-78-441-
7546. FAX: 81-78-441-7547.
† Gifu Pharmaceutical University.
‡ National Kaoshiung Normal University.
X Abstract published in Advance ACS Abstracts, August 1, 1996.
S0163-3864(96)00189-9 CCC: $12.00
© 1996 American Chemical Society and American Society of Pharmacognosy

Notes
J ournal of Natural Products, 1996, Vol. 59, No. 8 799
Ch a r t 1
Ta ble 1. 13C-NMR Spectral Data of Compound 3 in CD3OD
jashemsloside E decaacetate (3b) (1.3 mg). 3a : amor-
phous powder; H NMR (CDCl3) δ 1.03 (3H, d, J ) 7.0
1
carbon
C-1
C-3
C-4
C-5
C-6
C-7
C-8
C-9
C-10
C-11
OMe
C-1′, C-1′′′
C-2′, C-2′′′
C-3′, C-3′′′
C-4′, C-4′′′
C-5′, C-5′′′
C-6′, C-6′′′
δc
carbon
δc
Hz, H3-10), 1.35 (3H, s, H3-10′′), 1.68 (2H, m, H2-5′′),
1.80 (3H, d, J ) 1.0 Hz, H3-9′′), 1.85 (1H, ddd, J ) 15.5,
8.5, 5.0 Hz, H-6), 1.96 (1H, m, H-9), 1.91, 1.997, 2.004,
2.02, 2.03, 2.04, 2.10, 2.13, 2.15 (27H, each s, 9 × Ac),
2.20 (2H, m, H2-4′′), 2.24 (1H, m, H-8), 2.28 (1H, ddd, J
) 15.5, 8.5, 1.5 Hz, H-6), 3.01 (1H, br q, J ) 8.5 Hz,
H-5), 3.51 (1H, dd, J ) 11.0, 7.0 Hz, H-6′′′), 3.60 (1H,
ddd, J ) 9.5, 7.0, 2.0 Hz, H-5′′′), 3.69 (1H, dd, J ) 11.0,
2.0 Hz, H-6′′′), 3.69 (3H, s, COOMe), 3.75 (1H, ddd, J )
9.5, 4.5, 2.0 Hz, H-5′), 3.89 (1H, d, J ) 10.0 Hz, H-4′′′′),
3.97 (1H, d, J ) 10.0 Hz, H-4′′′′), 4.14 (1H, dd, J ) 12.0,
2.0 Hz, H-6′), 4.22 (1H, d, J ) 11.5 Hz, H-5′′′′), 4.33 (1H,
dd, J ) 12.0, 4.5 Hz, H-6′), 4.37 (1H, d, J ) 11.5 Hz,
H-5′′′′), 4.58 (1H, d, J ) 8.0 Hz, H-1′′′), 4.87 (1H, d, J )
8.0 Hz, H-1′), 4.91 (1H, t, J ) 9.5 Hz, H-4′′′), 4.95 (1H,
d, J ) 1.5 Hz, H-2′′′′), 4.98 (1H, dd, J ) 9.5, 8.0 Hz,
H-2′′′), 5.00 (1H, dd, J ) 9.5, 8.0 Hz, H-2′), 5.09 (1H, d,
J ) 1.5 Hz, H-1′′′′), 5.11 (1H, t, J ) 9.5 Hz, H-4′), 5.18
(1H, br t, J ) 5.0 Hz, H-7), 5.18 (1H, t, J ) 9.5 Hz,
H-3′′′), 5.23 (1H, t, J ) 9.5 Hz, H-3′), 5.24 (1H, dd, J )
17.5, 1.0 Hz, H-8′′), 5.26 (1H, d, J ) 2.5 Hz, H-1), 5.30
(1H, dd, J ) 11.0, 1.0 Hz, H-8′′), 5.72 (1H, dd, J ) 17.5,
11.0 Hz, H-7′′), 6.66 (1H, tq, J ) 7.5, 1.0 Hz, H-3′′), 7.26
(1H, br s, H-3); SIMS m/z [M + Na]+ 1251, 331, 217,
193; HRSIMS m/z [M + Na]+ 1251.4324 (calcd for
C56H76O30Na, 1251.4322). 3b: amorphous powder; 1H-
NMR (CDCl3) δ 1.03 (3H, d, J ) 7.0 Hz, H3-10), 1.36
(3H, s, H3-10′′), 1.68 (2H, m, H2-5′′), 1.80 (3H, d, J )
1.0 Hz, H3-9′′), 1.85 (1H, ddd, J ) 15.5, 8.5, 5.0 Hz, H-6),
1.95 (1H, m, H-9), 1.91, 1.996, 2.004, 2.02, 2.029, 2.032,
2.04, 2.09, 2.10, 2.12 (30H, each s, 10 × Ac), 2.18 (2H,
m, H2-4′′), 2.23 (1H, m, H-8), 2.27 (1H, ddd, J ) 15.5,
8.5, 1.5 Hz, H-6), 3.01 (1H, br q, J ) 8.5 Hz, H-5), 3.54
(1H, dd, J ) 11.0, 7.5 Hz, H-6′′′), 3.60 (1H, ddd, J )
9.5, 7.5, 2.0 Hz, H-5′′′), 3.67 (1H, dd, J ) 11.0, 2.0 Hz,
H-6′′′), 3.69 (3H, s, COOMe), 3.75 (1H, ddd, J ) 9.5, 5.0,
2.5 Hz, H-5′), 4.15 (1H, dd, J ) 12.5, 2.5 Hz, H-6′), 4.15
(1H, d, J ) 10.5 Hz, H-4′′′′), 4.22 (1H, d, J ) 10.5 Hz,
H-4′′′′), 4.33 (1H, dd, J ) 12.5, 5.0 Hz, H-6′), 4.52 (1H,
97.5
152.6
113.4
32.6
C-1′′
C-2′′
C-3′′
C-4′′
C-5′′
C-6′′
C-7′′
C-8′′
C-9′′
C-10′′
C-1′′′′
C-2′′′′
C-3′′′′
C-4′′′′
C-5′′′′
169.4
128.9
144.4
24.5
41.2
81.1
144.2
116.1
12.6
40.5
78.8a
41.1
47.3
13.8
169.4
51.8
23.7
111.1
78.2a
80.6
75.1
65.8
100.2
74.8
99.6
75.3
78.5a
71.9b
76.6
62.9
78.1a
71.7b
78.3a
62.8
a,b
Values with the same superscript are interchangeable.
3.17 (1H, dd, J ) 9.5, 8.0 Hz, H-2′′′), 3.21 (1H, dd, J )
9.5, 8.0 Hz, H-2′), 3.25 (1H, t, J ) 9.5 Hz, H-4′′′), 3.26
(1H, t, J ) 9.5 Hz, H-4′), 3.31 (1H, m, H-5′′′ or H-5′),
3.32 (1H, t, J ) 9.5 Hz, H-3′′′), 3.33 (1H, m, H-5′ or
H-5′′′), 3.38 (1H, t, J ) 9.5 Hz, H-3′), 3.54 (1H, dd, J )
11.5, 6.5 Hz, H-6′′′), 3.58 (2H, s, H2-5′′′′), 3.67 (1H, dd,
J ) 11.5, 5.5 Hz, H-6′), 3.69 (3H, s, COOMe), 3.76 (1H,
d, J ) 9.5 Hz, H-4′′′′), 3.87 (1H, d, J ) 2.5 Hz, H-2′′′′),
3.90 (1H, dd, J ) 11.5, 1.5 Hz, H-6′), 3.94 (1H, dd, J )
11.5, 2.0 Hz, H-6′′′), 3.96 (1H, d, J ) 9.5 Hz, H-4′′′′),
4.36 (1H, d, J ) 8.0 Hz, H-1′′′), 4.67 (1H, d, J ) 8.0 Hz,
H-1′), 4.97 (1H, d, J ) 2.5 Hz, H-1′′′′), 5.18 (1H, td, J )
5.0, 1.5 Hz, H-7), 5.23 (1H, dd, J ) 11.0, 1.0 Hz, H-8′′),
5.30 (1H, dd, J ) 17.5, 1.0 Hz, H-8′′), 5.31 (1H, d, J )
4.5 Hz, H-1), 5.94 (1H, dd, J ) 17.5, 11.0 Hz, H-7′′), 6.78
(1H, tq, J ) 7.5, 1.0 Hz, H-3′′), 7.43 (1H, d, J ) 1.5 Hz,
H-3); 13C-NMR data, see Table 1; HRSIMS m/z [M +
Na]+ 873.3371 (calcd for C38H58O21Na, 873.3365).
Acetyla tion of 3. J ashemsloside E (3) (5.1 mg) was
treated with Ac2O and pyridine (each 0.3 mL) at room
temperature for 2 h, and the product (8.6 mg) was
purified by preparative TLC with CHCl3-MeOH (9:1)
to afford jashemsloside E nonaacetate (3a ) (4.4 mg) and

800 J ournal of Natural Products, 1996, Vol. 59, No. 8
Notes
d, J ) 12.5 Hz, H-5′′′′), 4.58 (1H, d, J ) 8.0 Hz, H-1′′′),
4.78 (1H, d, J ) 12.5 Hz, H-5′′′′), 4.87 (1H, d, J ) 8.0
Hz, H-1′), 4.88 (1H, t, J ) 9.5 Hz, H-4′′′), 4.97 (1H, dd,
J ) 9.5, 8.0 Hz, H-2′′′), 5.00 (1H, dd, J ) 9.5, 8.0 Hz,
H-2′), 5.02 (1H, br s, H-1′′′′), 5.10 (1H, t, J ) 9.5 Hz,
H-4′), 5.18 (1H, br t, J ) 5.0 Hz, H-7), 5.18 (1H, t, J )
9.5 Hz, H-3′′′), 5.23 (1H, t, J ) 9.5 Hz, H-3′), 5.25 (1H,
dd, J ) 17.5, 1.0 Hz, H-8′′), 5.26 (1H, d, J ) 2.5 Hz,
H-1), 5.30 (1H, dd, J ) 11.0, 1.0 Hz, H-8′′), 5.33 (1H, br
s, H-2′′′′), 5.72 (1H, dd, J ) 17.5, 11.0 Hz, H-7′′), 6.66
(1H, tq, J ) 7.5, 1.0 Hz, H-3′′), 7.26 (1H, br, s, H-3);
SIMS m/z [M + Na]+ 1293, 331, 259, 193; HRSIMS m/z
[M + Na]+ 1293.4393 (calcd for C58H78O31Na, 1293.4427).
Zem p len Rea ction of 3. A solution of 3 (5.6 mg) in
dry MeOH (0.5 mL) and 0.1 M NaOMe (0.5 mL) was
heated for 8 h under reflux. The reaction mixture was
neutralized with Amberlite IR-120 (H+ form) and con-
centrated in vacuo. The resulting residue (7.6 mg) was
purified by preparative HPLC (µBondasphere, 5 µM, C18
-100 Å, MeOH-H2O, 1:1) to give 4 (0.6 mg) and 6 (1.4
mg). Compound 4 was identified as loganin6 (1H NMR,
3.75 (1H, d, J ) 9.5 Hz, H-4′′′′), 3.87 (1H, d, J ) 2.0 Hz,
H-2′′′′), 3.95 (1H, d, J ) 9.5 Hz, H-4′′′′), 4.35 (1H, d, J )
8.0 Hz, H-1′′′), 4.97 (1H, d, J ) 2.0 Hz, H-1′′′′), 5.22 (1H,
dd, J ) 11.0, 1.0 Hz, H-8′′), 5.29 (1H, dd, J ) 18.0, 1.0
Hz, H-8′′), 5.93 (1H, dd, J ) 18.0, 11.0 Hz, H-7′′), 6.77
(1H, tq, J ) 7.5, 1.0 Hz, H-3′′); HRSIMS m/z [M + Na]+
515.2121 (calcd for C38H58O21Na, 515.2103).
Ack n ow led gm en ts. The authors are grateful to Dr.
M. Sugiura, Kobe Pharmaceutical University for 1H-
and 13C-NMR spectra and to Dr. K. Saiki, Kobe Phar-
maceutical University, for mass spectral measurements.
Refer en ces a n d Notes
(1) Tanahashi, T.; Shimada, A.; Nagakura, N.; Inoue, K.; Ono, M.;
Fujita, T.; Chen, C.-C. Chem. Pharm. Bull. 1995, 43, 729-733.
(2) Gross, G.-A.; Sticher, O.; Anklin, C. Helv. Chim. Acta 1987, 70,
91-101.
(3) Kitagawa, I.; Hori, K.; Sakagami, M.; Hashiuchi, F.; Yoshikawa,
M.; Ren, J . Chem. Pharm. Bull. 1993, 41, 1350-1357.
(4) Kouno, I.; Yasuda, I.; Mizoshiri, H.; Tanaka, T.; Murabayashi,
N.; Yang, D.-M. Phytochemistry 1994, 37, 467-472.
(5) Voirin, S.; Baumes, R.; Bayonove, C.; M’Bairaroua, O.; Tapiero,
C. Carbohydr. Res. 1990, 207, 39-56.
1
SIMS, HPLC). 6: amorphous powder; H NMR (CD3-
(6) Kawai, H.; Kuroyanagi, M.; Ueno, A. Chem. Pharm. Bull. 1988,
36, 3664-3666.
OD) δ 1.40 (3H, s, H3-10′′), 1.70 (2H, m, H2-5′′), 1.81
(3H, d, J ) 1.0 Hz, H3-9′′), 2.29 (2H, m, H2-4′′), 3.16
(1H, dd, J ) 9.0, 8.0 Hz, H-2′′′), 3.57 (2H, s, H2-5′′′′),
NP960189L