Fang-You Chen

Neuroprotective Dihydroagarofuran Sesquiterpene Derivatives from the Leaves of Tripterygium wilfordii

Thirteen dihydroagarofuran derivatives, including 12 new sesquiterpenoid esters and one known sesquiterpenoid alkaloid, were obtained from the leaves of Tripterygium wilfordii. Spectroscopic techniques and the ECD method were used for the structure elucidation of the compounds. The structures of compounds 1 and 8 were confirmed by single-crystal X-ray crystallographic analyses. Compounds 8, 9, 11, 12, and 13 increased cell viability of the okadaic acid treated PC12 cells from 60.4 ± 23.0% to 72.4 ± 14.1, 71.5 ± 11.5, 75.7 ± 15.6, 81.2 ± 13.1, and 86.2 ± 25.5% at 10 μM, respectively.

Anti-inflammatory pentacyclic triterpenes from the stems of Euonymus carnosus

Three new lupane-type triterpenoids (1-3), three new oleane-type triterpenoids (4-6), as well as two known compounds (7-8) were isolated from Euonymus carnosus. The structures of the compounds were elucidated on the basis of spectroscopic data analyses, including UV, IR, MS, and NMR experiments. The inhibitory on LPS-induced NO production in microglia BV2 cells of compounds 1-8 were also evaluated. Compounds 1 and 2 showed moderate abilities to inhibit NO production, with IC50 values of 5.99 and 8.47μM, respectively.

Triptergosidols A-D, nerolidol-type sesquiterpene glucosides from the leaves of Tripterygium wilfordii

Four new nerolidol-type sesquiterpene glucosides, triptergosidols A-D (1-4) were isolated from the leaves of Tripterygium wilfordii. Three aglycones, named triptergerols A (1a), B (2a), and C (3a), were acquired by enzymatic hydrolysis of 1-3. The structures of nerolidol-type sesquiterpenes were elucidated on base of kinds of spectroscopic analysis, and their absolute configurations were determined by CD method. In addition, compounds 1-4 were tested for cytotoxicity against two cell lines and inhibitory effects against NO production in RAW264.7 macrophage.

Alkaloids from the stems of Clausena lansium and their neuroprotective activity

Eight new alkaloids, including three pairs of enantiomers (+)-(2′S,3′R)-clauselansine A (1a) and (−)-(2′R,3′S)-clauselansine A (1b); (+)-(2′S,3′R)-clauselansine B (2a) and (−)-(2′R,3′S)-clauselansine B (2b); (+)-(3S,4R,5S,6S)-clauselansine C (3a) and (−)-(3R,4S,5R,6R)-clauselansine C (3b), (+)-(1′R,2′R,6′R)-claulansine B (4a), and (+)-(1′R,2′R)-claulansine D (5a), together with twelve known alkaloids (4b, 5b, 6a, 6b, 7a, 7b and 8–13) were isolated from the stems of Clausena lansium. Their structural elucidation and stereochemistry determination were achieved by spectroscopic and chemical methods including 1D and 2D NMR experiments, especially the employment of electronic circular dichroism calculation spectra, Moshers method, and Snatzkes method expressed by the induced circular dichroism spectrum. Compounds 1b, 2a, 3b, 5a, and 5b inhibited PC12 cell damage induced by Okadaic Acid, and increased cell viability from 70.5 ± 5.4% to 83.4 ± 4.1%, 91.2 ± 10.1%, 83.5 ± 7.8%, 89.7 ± 4.8%, 83.3 ± 5.9% at 10 μM, respectively.

Two new saponins from the leaves of Panax notoginseng

Abstract Two new saponins, notoginsenosides Ng1 (1) and Ng2 (2), together with seven known compounds (3–9), were isolated from the leaves of Panax notoginseng. Their structures were elucidated by UV, IR, HRESIMS, and NMR experiments. Compounds 6 and 7 showed moderate cytotoxic activities against HCT-116, with IC50 values of 4.98 and 0.64 μmol/L, respectively.

Nototronesides A–C, Three Triterpene Saponins with a 6/6/9 Fused Tricyclic Tetranordammarane Carbon Skeleton from the Leaves of Panax notoginseng

Three triterpene saponins, nototronesides A-C (1-3), possessing an unprecedented 6/6/9 fused tricyclic tetranordammarane core, were isolated from the leaves of Panax notoginseng. Their structures were elucidated on the basis of spectroscopic data, and the structure of sapogenin (1a) was further confirmed by X-ray crystallography. The existence of 1-3 adds a new dimension to the diversity of the triterpene family. Moreover, compound 2 showed a moderate neuroprotective effect on serum deficiency-induced cellular damage in PC12 cells.

Magterpenoids A–C, Three Polycyclic Meroterpenoids with PTP1B Inhibitory Activity from the Bark of Magnolia officinalis var. biloba

Magterpenoid A (1), possessing a rare 4,6,11-trioxatricyclo[5.3.1.01,5]undecane framework with an irregular monoterpenoid moiety, magterpenoid B (2), with an unprecedented 6/6/6/6 polycyclic skeleton, and magterpenoid C (3), a novel terpenoid quinone with a C6-C3 unit, were isolated from the bark of Magnolia officinalis var. biloba. Plausible biogenetic pathways of 1-3 are presented. Compounds 1 and 3 exhibited significant PTP1B inhibitory activities with IC50 values of 1.44 and 0.81 μM, respectively.

Hepatoprotective glycosides from the rhizomes of Imperata cylindrical

Abstract Three new C-methylated phenylpropanoid glycosides (1, 2), a new 8–4′-oxyneolignan (3), together with two known analogs (4, 5), were isolated from the rhizomes of Imperata cylindrical Beauv. var. major (Nees) C. E. Hubb. Their structures were determined by spectroscopic and chemical methods. Compounds 1, 2, and 5 (10 μM) exhibited pronounced hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced HepG2 cell damage in vitro assays. Furthermore, their antioxidant activities against Fe2+-cysteine-induced rat liver microsomal lipid peroxidation and the effects on the secretion of TNF-α in murine peritoneal macrophages (RAW264.7) induced by lipopolysaccharides were evaluated.

Diterpenoids and lignans from the leaves of Tripterygium wilfordii

Three new diterpenoids (1-3) and three new esterifying lignans (4-6) were isolated from the leaves of Tripterygium wilfordii. The structures of these compounds were elucidated on the basis of spectroscopic techniques (UV, IR, NMR, HRESIMS, and ECD method). At 10 μmol/L, compounds 4-6 showed moderate inhibitory effects on nitric oxide production in LPS-induced macrophages with inhibitory rate >80%.

Chemical constituents from the stems of Hydrangea paniculata

Abstract Further study on the constituents from the stems of Hydrangea paniculata Sieb resulted in isolation of two new compounds 1–2, including 1 monoterpenoid and 1 phenolic glycoside, along with 10 known compounds. Their structures were elucidated on the basis of spectroscopic data, including UV, IR, MS, and NMR experiments, along with chemical methods. At 10 μM, compounds 1 and 2 exhibited comparable activities with bicyclol in vitro assays for hepatoprotective activity against APAP-induced HepG2 cell damage.