Nailiang Zhu

Antimalarial and Antiproliferative Cassane Diterpenes of Caesalpinia sappan.

Bioassay-guided fractionation of a methanol extract of the seeds of Caesalpinia sappan led to the isolation of 12 new cassane-type diterpenes, caesalsappanins A-L (1-12). Their structures were elucidated on the basis of NMR and HRESIMS analysis, and the absolute configuration of compound 1 was determined by single-crystal X-ray crystallography. All isolated compounds were tested against a chloroquine-resistant Plasmodium falciparum strain for antiplasmodial activities and against a small panel of human cancer cell lines for antiproliferative activities. Compounds 7 and 8 displayed antimalarial activity against the chloroquine-resistant K1 strain of P. falciparum with IC50 values of 0.78 and 0.52 μM and selectivity indices of 17.6 and 16.4, respectively. Compound 10 showed antiproliferative activity against the KB cancer cell line with an IC50 value of 7.4 μM.

Two new abietane diterpenoid glycosides from Clinopodium chinense

Abstract Two new abietane diterpenoid glycosides, named clinopoditerpenes B (1) and C (2), were isolated from Clinopodium chinese. The structures of the new compounds were determined on the basis of extensive spectral analysis. Compound 1 exhibited cardioprotective effect against H2O2-induced apoptosis in H9c2 cells.

Cassane diterpenes with oxygen bridge from the seeds of Caesalpinia sappan.

The seeds of the medicinal plant Caesalpinia sappan yielded fourteen cassane-type diterpenes, including six new rearranged ones named as caesalppans A-F (1-6). Their structures were elucidated by spectroscopic analysis and comparison with literature data. The isolated new compounds 1-6 possess lactone-type cassane diterpenoid skeleton with an oxygen bridge between C-19 and C-20, and were tested cytotoxic activity against four cancer cell lines using the MTT method.

Four new phenolic acid with unusual bicycle [2.2.2] octane moiety from Clerodendranthus spicatus and their anti-inflammatory activity

Four new phenolic acids, clerodens A-D (1-4) possessing an unusual bicycle [2.2.2] octane moiety were isolated from the whole plants of Clerodendranthus spicatus. Their structures were elucidated by extensive spectroscopic methods, including NMR, MS, and ECD data. All isolates were evaluated for their anti-inflammatory activities on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7, and compound 4 showed significant inhibitory activities with IC50 value of 6.8 μM.

New cucurbitane triterpenoids with cytotoxic activities from Hemsleya penxianensis

Seven new cucurbitane triterpenoids, Pengxianencins A-G (1-7) including one alkaloid, were isolated from the ethanol extract of the tubers of Hemsleya penxianensis. Their structures were elucidated on the basis of extensive spectroscopic data, including 1D and 2D NMR spectra as well as HR-ESI-MS. The evaluation of inhibition activity against human Hela, MCF-7, and A-549 cell lines showed that compounds 1, 4, 6, 7 have different levels of cytotoxic activities, with IC50 values ranging from 1.67 to 45.28μM.

Hepatoprotective Effect of Aqueous Extract from the Seeds of Orychophragmus violaceus against Liver Injury in Mice and HepG2 Cells

Orychophragmus violaceus (O. violaceus) is a kind of edible wild herb in north China and its seeds have medical potential, however, the effect of O. violaceus seeds on liver injury and the mechanism of action remains poorly understood. Thus, the purpose of the present study is to investigate the effect of O. violaceus seeds on liver injury and further explore the molecular mechanism of the beneficial effects using aqueous extract from the seeds of O. violaceus (AEOV). Mice were orally administrated with saline, AEOV, and biphenyldicarboxylate for 4 days, and were then injected subcutaneously with 0.1% carbon tetrachloride (CCl4) dissolved in corn oil. Sixteen hours later, mice were sacrificed and blood samples were collected. Then, the serum was separated and used for biochemical assay. Livers were excised and were routinely processed for histological examinations. Enzyme activities and protein levels in liver homogenates were detected using commercial kits or by western blot analysis. Additionally, the hepatoprotective effect of AEOV in vitro was evaluated using epigoitrin, the major alkaloid compound isolated from AEOV. We found that AEOV attenuated liver injury induced by CCl4 as evidenced by decreased levels of alanine aminotransferase (ALT) and aminotransferase (AST) in serum, improvement of liver histopathological changes, and substantial attenuation of oxidative stress and inflammation via regulation of nuclear factor-erythroid 2-related factor-2 (Nrf2) and nuclear factor κB (NFκB) pathways. These effects of AEOV were comparable to that of biphenyldicarboxylate which was commonly used as a hepatoprotective reference. Moreover, pretreatment of HepG2 cells with epigoitrin improved cell viability, decreased lactate dehydrogenase (LDH) and malondialdehyde (MDA) levels, increased superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity, attenuated the NFκB pathway, and elevated the Nrf2 pathway after exposure to H2O2. These results suggest that AEOV could effectively prevent CCl4-induced liver injury in mice via regulating the Nrf2 and NFκB pathways, and reveal the cytoprotective effects of epigoitrin against H2O2-induced oxidative stress in HepG2 cells.

Clinoposides A–F: meroterpenoids with protective effects on H9c2 cardiomyocyte from Clinopodium chinense

Six novel flavonoid–triterpene saponin meroterpenoids, clinoposides A–F (1–6), with two unusual skeletons were isolated from Clinopodium chinense. Clinoposides A–F represent a new class of isopentenyl flavonoid saponin. Their structures were determined based on spectroscopic data and chemical methods. The relative and absolute stereochemistries were assigned using a combination of NOESY and ECD. A possible biogenetic pathway for 1–6 is proposed. The protective effects of clinoposides A–F against H2O2-induced H9c2 cardiomyocyte injury were tested, and all compounds exhibited significantly dose-dependent effects, clinoposides B, D and F showed better protective effects as evidence by increased levels of SOD, CAT and GSH-Px but reduced MDA, LDH, caspase-3 and -9 levels.

New stigmastane type of steroidal glycosides from the roots of Vernonia cumingiana

GRAPHICAL ABSTRACT ABSTRACT Two new stigmastane type of steroidal glycosides, vernoniacums A and B (1 and 2), with a △7,9(11) steroidal core were isolated from the roots of Vernonia cumingiana. Their structures were elucidated based on various spectroscopic techniques, including IR, HR-FAB-MS, and 1D and 2D NMR. Both compounds were evaluated for their cytotoxicity against HeLa and HCT-8 cells, and compound 1 showed mild activity against the tested cell lines with IC50 values of 15.8 and 35.7 pounds were evaluated for their cytotoxicity against HeLa and HCT-8 cells, and compound 1 showed mild activity against the tested cell lines with IC50 values of 15.8 and 35.7 μM, respectively.

Pyrrole Alkaloids from the Edible Mushroom Phlebopus portentosus with Their Bioactive Activities

Seven pyrrole alkaloids, three of which are novel (phlebopines A–C (1–3)), were isolated from the fruiting bodies of the edible mushroom Phlebopus portentosus. Their structures were determined on the basis of spectroscopic data. All the isolated compounds were tested for their neuroprotective properties and acetylcholine esterase (AChE) inhibition activities. Compound 7 displayed remarkable neuroprotective effects against hydrogen peroxide (H2O2)-induced neuronal-cell damage in human neuroblastoma SH-SY5Y cells.

Semisynthesis and Biological Evaluation of Oleanolic Acid 3-O-β-d-Glucuronopyranoside Derivatives for Protecting H9c2 Cardiomyoblasts against H2O2-Induced Injury

A series of novel oleanolic acid 3-O-β-d-glucuronopyranoside derivatives have been designed and synthesized. Biological evaluation has indicated that some of the synthesized compounds exhibit moderate to good activity against H2O2-induced injury in rat myocardial cells (H9c2). Particularly, derivative 28-N-isobutyl ursolic amide 3-O-β-d-galactopyranoside (8a) exhibited a greater protective effect than the positive control oleanolic acid 3-O-β-d-glucuronopyranoside, indicating that it possesses a great potential for further development as a cardiovascular disease modulator by structural modification.