Journal of Asian Natural Products Research
459
0
00
000
00
00
00
4
H-1 at d 4.43 (Glc H-1 ) with Glc C-6
.92 with C-4 , 4 , 4 at d 159.4, and Glc
0
H-1 at d 5.07 with C-4 at d 159.2, H-7
H
C
0000
C
000
00
at d 5.12 with the carbonyls at d 176.9,
H C
H
1
1
at d 70.7 further confirmed the glycosyla-
C
tion sequence and position (Figure 2). The
3
larger coupling constants of JH-1,H-2
together with H– H COSY and HSQC
data, further confirmed the above structure
(Figure 2).
confirmed b-orientation at the anomeric
centers for four glucoses. Furthermore, the
two doublets of two methylene protons and
two carbon signals of three carbonyl groups
at d 173.0 (two carbons) and 176.0 in citrate
moiety further indicated that the fourth
3
.
Experimental
3.1. General experimental procedures
Optical rotations were measured on a
JASCO P-1020 spectrometer (Jasco,
Tokyo, Japan). IR spectra were recorded
on a fourier transform infrared (FT-IR)
spectrometer (Perkin-Elmer, Tucson, AZ,
USA) as KBr pellets with absorption given
00
glucose was located at Glc , which formed
1
1
a symmetrical situation. HZ H COSY,
HSQC data and hydrolysis results were all
consistent with the results deduced above.
Thus, the structure of 1 was elucidated as
21
in cm . UV spectra were acquired on a SP-
1901 spectrometer (Shanghai Spectrum,
Shanghai, China). ESI-MS were obtained
with a Finnigan TSQ MS/MS spectrometer
(Thermo, San Jose, CA, USA) in m/z
(rel. %). HR-FTMS were recorded on a
Bruker Apexiii 7.0 Tesla FTMS (Bruker
Daltonics, Billerica, MA, USA). 1D and 2D
NMR spectra were measured on a Bruker
DRX400 spectrometer (Bruker, Fallanden,
1
2
,3-di-[4-O-(b-D-glucopyranosyl)benzyl]-
-{4-O-[b-D-glucopyranosyl-(1 ! 6)-b-
D-glucopyranosyl]benzyl} citrate, named
as parishin G.
Compound 2 was also obtained as a
white amorphous powder. The IR spectrum
showed absorptions for hydroxyl groups at
2
1
3
1
402 cm , ester groups at 1732 and
21
231 cm , as well as aromatic ring at 1614
21
and 1513 cm . The molecular formula was
established as C H O from the pseudo-
Switzerland) in D O with 2,2-dimethyl-2-
2
silapentane-5-sulfonate sodium salt as an
internal standard. Diaion HP-20 was pur-
chased from Mitsubishi Kagaku (Tokyo,
Japan). PreparativeHPLC (Waters, Milford,
MA, USA): Waters Delta Prep 4000 with a
Waters 996 PDA detector; Nova-Pak C18
column (200 £ 40mm i.d., 6 m; Waters)
with a flow rate of 60ml/min; Superiorex
ODS column (250 £ 20 mm i.d., 5 m;
Shiseido, Tokyo, Japan) with a flow rate of
15ml/min; UV detection at 270 nm.
19 24 13
þ
molecular ion at m/z 483.1107 [M þ Na] in
the HR-FTMS. The negative ESI-MS/MS
showed fragment ions at m/z 173 [M 2 H-
2
2
with mono-substituted parishin [11].
68-H O] , which was in accordance
2
The NMR spectra of 2 showed similar
patterns with that of mono-substituted
parishin E (1-[4-O-(b-D-glucopyranosyl)
benzyl] citrate) [10], except for the citric
acidmoiety.Inthecitricacidmoietyof2,the
two doublets at d 2.94 (2H, d, J ¼ 15.9Hz)
H
and 2.74 (2H, d, J ¼ 15.9Hz) for two
3
.2. Plant material
methylenes, and two carbon signals for three
carbonyl groups at d 175.7 (two carbons)
The rhizome of G. elata was collected
from Guangyuan city, Sichuan Province,
China, and identified by Professor Sui-
Qing Chen (Henan College of Traditional
Chinese Medicine). The voucher specimen
(No. 050528) is deposited in the Laboratory
of Medicinal Chemistry, Dalian Institute
of Chemical Physics, Chinese Academy of
Sciences.
C
1
76.9 indicated that the citrate moiety
existed in a symmetrical situation, rather
than four doublets for two methylene
protons and three separated carbon signals
forthreecarbonylgroupsinparishinE.Thus,
compound 2 was confirmed as 2-[4-O-(b-D-
glucopyranosyl) benzyl] citrate, named as
parishin H. The HMBC correlations of Glc
Wang, Li
