Xing Fu Cai

Quantitative determination of eleutheroside B and E fromAcanthopanax species by high performance liquid chromatography

Reversed-phase high performance liquid chromatographic method was applied for the determination of eleutheroside B and E in the variousAcanthopanax species collected in Korea. The stationary phase used was Zorbax 300 SB C18 and a mobile phase program was used, which started at 6% acetonitrile for 2 min, and then a linear gradient was operated for the next 18 min to 17% acetonitrile at a flow rate of 1.0 ml/min. The column effluent was monitored at UV 210 nm. Identification was carried out by comparing the retention time and the LC/MS spectrum of each peak corresponding to eleutheroside B and E from sample with those of standards. In general, the contents of eleutheroside B and E in stems were higher than those in roots.Acanthopanax species could be classified into two groups based upon the contents of eleutheroside B and E: one group contains no or very little eleutheroside B and another contains both eleutheroside B and E.

Two new phenylpropanoid glycosides from the stem bark of Acanthopanax trifoliatus.

Two new phenylpropanoid glycosides, 1-β-D-glucopyranosyl-2,6-dimethoxy-4-propenylphenol (1) and 1-[β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl]-2,6-dimethoxy-4-propenylphenol (2) were isolated from the stem bark ofAcanthopanax trifoliatus along with four known compounds (3–6). Their structures were established on the basis of spectral and chemical evidences.

Triterpenoids fromAcanthopanax koreanum root and their inhibitory activities on NFAT transcription

Two triterpenoids (1,4) and two triterpenoid glycosides (2,3) were isolated from the root ofAcanthopanax koreanum (Araliaceae). Their structures were identified as impressic acid (1), acankoreoside A (2), 3-epi-betulinic acid 28-0-[α-L-rhamnopyranosyl(1→4)-p-D-glucopyrano-syl(1→6)]-β-D-glucopyranosyl] ester (3), and ursolic acid (4) by physicochemical and spectroscopic methods. Of these compounds, impressic acid (1) exhibited a potent inhibitory activity against NFAT transcription factor (IC50:12.65 μ.M).

Inhibitory lignans against NFAT transcription factor from Acanthopanax koreanum

Three lignans isolated from the roots ofA. koreanum (Araliaceae), namely eleutheroside E (1), tortoside A (2), and hemiariensin (4), were evaluated for their ability to inhibit NFAT transcription factor. Of these compounds, compound4, possessing a diarylbutane skeleton, exhibited potent inhibitory activity against NFAT transcription factor (IC50: 36.3 +- 2.5 μM). However, the activities of 1 (IC50: > 500 μM) and2 (IC50: 136.1 +- 9.4 μM), which possess bisaryldioxabicy-clooctane skeletons, were lower. As the lignan derivatives of the same skeletons, hinokinin (5) and (-)-yatein (6) with diarylbutane skeletons and (+)-syringaresinol (3) with a bisaryldioxabicy-clooctane skeleton were also studied for their inhibitory effects on NFAT transcription factor.

Inhibitory effect of kaurane type diterpenoids fromAcanthopanax koreanum on TNF-α secretion from trypsin-stimulated HMC-1 cells

Five known kaurane type diterpenoids, 16αH,17-isovaleryloxy-ent-kauran-19-oic acid (1), 16α-hydroxy-17-isovaleryloxy-ent-kauran-19-oic acid (2), paniculoside-IV (3), 16α-hydroxy-ent-kau-ran-19-oic acid (4), andent-kaur-16-en-19-oic acid (5) were isolated from the root ofAcanthopanax koreanum by repeated column chromatography and reversed phase preparative HPLC. The structures of these compounds were established from physicochemical and spectral data. Among the isolated compounds 16αH,17-isovaleryloxy-ent-kauran-19-oic acid (1) showed potent inhibitory activity (IC50 value, 16.2 uM) on TNF-α secretion from HMC-1, a trypsin-stimulated human leukemic mast cell line.

The inhibition of diacylglycerol acyltransferase by terpenoids from Youngia koidzumiana.

The EtOAc extract of Youngia koidzumiana significantly inhibited the diacylglycerol acyltransferase (DGAT) from rat liver microsomes. Bioactivity-guided fractionation led to the isolation of nine compounds, the structures of which were established using physicochemical and spectral data. Of the isolated compounds, oleanolic acid (2), methyl ursolate (7) and corosolic aicd (8) inhibited DGAT, with IC50 values of 31.7, 26.4, and 44.3 μM, respectively. However, sesquiterpenoids showed only weak inhibitory effects toward DGAT.

Gymnastone, A New Benzofuran Derivative from Gymnaster koraiensis

A new benzofuran derivative, named gymnastone [5-hydroxy-6-acetyl-2-(2-propane-1,2,3-triol)-benzofuran (1)], was isolated from the aerial part ofGymnaster koraiensis, together with viscidone (2) by repeated column chromatography. The structures of both compounds were identified by physico-chemical and spectral analysis including COSY, HMQC, and HMBC experiments.

A New 24-nor-lupane-glycoside ofAcanthopanax trifoliatus

A new 24-nor-lupaneglycoside was isolated from the leaves ofAcanthopanax trifoliatus. Based on spectroscopic data its chemical structure was determined as 24-nor-11α-hydroxy-3-oxo-lup-20(29)-en-28-oic acid 28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester.