Hosimosines A-E, structurally diverse cytisine derivatives from the seeds of Ormosia hosiei Hemsl. et Wils.

Ormosia hosiei Hemsl. et Wils (Fabaceae family) is an arbor species endemic to China. The seeds of O. hosiei have been used as traditional Chinese medicine to treat hernia, abdominal pain, blood stasis and amenorrhea. Cytisine-like and angustifoline type alkaloids were main components identified from this plant. In our research on the bioactive alkaloids from the promising Chinese medicinal plants, four new angustifoline type alkaloids (1-4) and a new cytisine-like alkaloid (5), named hosimosine A-E, together with 13 known analogues (6-18) were isolated from the seeds of O. hosiei. Their structures were elucidated by the extensive spectroscopic methods, especially the interpretation of NMR spectra and specific rotations, along with the methods of NMR and ECD calculation. Compounds 1-4 were identified as two pairs of epimers, whose relative configurations were deduced from density functional theory (DFT) calculations of NMR chemical shifts and DP4+ analysis, and absolute configurations were determined by comparison of their experimental and theoretical ECD spectra. Compound 5 displayed two sets of NMR data caused by the existence of tautomeric forms. Compounds 14, 17 and 18 were determined to be enantiomers of literature compounds. Some of the isolates exhibited moderate cytotoxic effects against HepG2, A2780 and MCF-7 cells.

[Research progress on chemical structures and pharmacological effects of natural cytisine and its derivatives].

Cytisine derivatives are a group of alkaloids containing the structural core of cytisine, which are mainly distributed in Fabaceae plants with a wide range of pharmacological activities, such as resisting inflammation, tumors, and viruses, and affecting the central nervous system. At present, a total of 193 natural cytisine and its derivatives have been reported, all of which are derived from L-lysine. In this study, natural cytisine derivatives were classified into eight types, namely cytisine type, sparteine type, albine type, angustifoline type, camoensidine type, cytisine-like type, tsukushinamine type, and lupanacosmine type. This study reviewed the research progress on the structures, plant sources, biosynthesis, and pharmacological activities of alkaloids of various types.

[Two novel cephalotaxine-type alkaloids from Cephalotaxus sinensis].

Silica gel, octadecyl-silica(ODS), Sephadex LH-20, and semi-preparative high performance liquid chromatography(HPLC) was performed to isolate nine cephalotaxine-type alkaloids from Cephalotaxus sinensis: 8-oxodeoxyharringtonine(1), 8-oxonordeoxyharringtonine(2), cephafortunine A(3), 8-oxocephalotaxine(4), deoxyharringtonine(5), acetylcephalotaxine(6), cephalotaxine(7), epicephalotaxine(8), and cephalotaxinone(9). Compounds 1 and 2 were identified for the first time and their structures were determined by high-resolution-electrospray ionization-mass spectrometry(HR-ESI-MS), nuclear magnetic resonance(NMR), and electronic circular dichroism(ECD). Compounds 1-3 and 5 significantly inhibited the transcription of nuclear factor kappa B(NF-κB), with the half-maximal inhibitory concentration(IC_(50)) of(3.91±0.70),(2.99±0.45),(7.84±0.51), and(1.46±0.17) µmol·L~(-1), respectively.

Abieshanesides A and B, two unique ent-18,19-dinoricetexane diterpenoid glycosides from Abies beshanzuensis M.H. Wu.

Two unprecedented ent-18,19-dinoricetexane diterpenoid glycosides, named abieshanesides A (1) and B (2), together with seven known compounds, have been isolated from the dead trunks and branches of Abies beshanzuensis M.H. Wu. To our knowledge, abieshanesides A and B represent the first ent-18,19-dinoricetexane diterpenoid glycosides found in natural sources. Their structures and absolute configurations were elucidated by using a combination of spectroscopic techniques and comparison of experimental and calculated electronic circular dichroism (ECD) data. The MTT experiments showed that (E)-resveratrol (7) could inhibit viability of MH7A cells with the IC50 value of 12.5 µM. Compound 7 was able to block MH7A cell proliferation and was associated with G0/G1-phase cell cycle arrest. Flow cytometric analysis showed that the treatment by 7 significantly induced the proliferation of MH7A cells in a dose-dependent manner.

Khayalactone- and phragmalin-type limonoids with PTP1B inhibitory activity from Trichilia sinensis Bentv.

An investigation on the extract from the plant Trichilia sinensis Bentv. led to the isolation of 13 new limonoids (1-13), in which two were of khayalactone skeleton and 11 were phragmalin-type limonoids, and eight known phragmalin-type limonoids (14-21). Their structures were elucidated by using spectroscopic techniques and HRESIMS experiment. Compounds 6 and 17 displayed potent protein tyrosine phosphatase 1B inhibitory activity with IC50 values of 1.2 ± 0.1 and 8.1 ± 0.5 µM, respectively.

Lignans from Schisandra chinensis ameliorate alcohol and CCl4-induced long-term liver injury and reduce hepatocellular degeneration via blocking ETBR.

ETHNOPHARMACOLOGICAL RELEVANCE: Chemical hepatotoxicity, especially alcoholic liver injury (ALI), commonly occurs in young and middle-aged people who drink heavily. ALI is extremely harmful and can induce severe disease states, such as hepatitis, liver fibrosis, cirrhosis, or liver cancer, which are similar to CCl4-induced liver disease states in animals. In recent studies, the pathological changes of hepatocytes and the hepatic stellate cell have shown a significant connection between endoplasmic reticulum (ER) stress and the development of liver pathology in patients. However, the detailed pathological mechanism needs to be further studied. Schisandra chinensis, (S. chinensis), a fruit-bearing vine used in Traditional Chinese Medicine (TCM), has been used to treat chronic or acute diseases, including liver disease. S. chinensis-derived lignans (SCDLs) in particular have been shown to alleviate liver pathological changes. AIM OF THE STUDY: This study sought to elucidate the mechanisms underlying SCDL-mediated hepatoprotection. MATERIALS AND METHODS: We first used in silico target prediction and computational simulation methods to identify putative lignan-binding targets relative to the hepatoprotective effect. A gene microarray analysis was performed to identify differently expressed genes that might have significance in the disease pathological process. We then used histological analyses in a mice hepatotoxicity model to test the effectiveness of SCDLs in vivo, and a hepatocellular toxicity model to analyze the candidate-compound-mediated hepatoprotection and expression states of the key targets in vitro. RESULTS: The in silico analysis results indicated that endothelin receptor B (ETBR/EDNRB) is likely a significant node during the liver pathological change process and a promising key target for the SCDL compound schisantherin D on the hepatoprotective effect; experimental studies showed that schisantherin D alleviated the EtOH- and ET-1-induced HL-7702 cell (belongs to liver parenchymal cell lines) injury ratio, decreased the expression of ETBR, and inhibited ECMs and ET-1 secretion in LX-2 cells (one form of hepatic stellate cells). SCDLs ameliorated EtOH- and CCl4-induced fibrosis formation in mice liver tissue. Liver tissue western blots of SCDL-treated mice showed downregulated α-SMA, ETBR, PLCß, CHOP, Bax, and the apoptotic factors of cleaved-caspase 12, cleaved-caspase 9, and cleaved-caspase 3 hinted at an anti-apoptosis and hepatoprotective effect. The SCDL treatment also elevated serum glutathione (GSH) and reduced the serum-transforming growth factor-ß1 (TGF-ß1) level. CONCLUSION: The findings indicated that SCDLs prevent hepatotoxicity via their anti-fibrotic, anti-oxidant, and anti-apoptosis properties. ETBR may be the key factor in promoting chemical hepatotoxicity.

[Research advances on chemical constituents from Calycanthaceae plants and their pharmacological activities].

Calycanthaceae family comprises of four genera including Chimonanthus, Sinocalycanthus, Calycanthus, and Idiospermum. The plants of Calycanthaceae are popular ornamental shrubs and used as foods and medicines, which are mainly distributed in China, North America, and Australia. The plants of Calycanthaceae are rich in volatile components, alkaloids, sesquiterpenes and coumarins. Dimeric piperidinoquinoline and dimeric pyrrolidinoindoline alkaloids, dimeric and/or trimeric coumarins are characteristic compositions in these plants. In order to provide timely reference for further investigation and development of Calycanthaceae plants, we made a systemic review on chemical constituents, i.e. alkaloids, terpenoids, flavonoids, coumarins, and steroids, from Calycanthaceae plants, focusing on their chemical structures and pharmacological activities.

Cephalotanins A-D, Four Norditerpenoids Represent Three Highly Rigid Carbon Skeletons from Cephalotaxus sinensis.

Four polycyclic norditerpenoids, cephalotanins A-D (1-4) representing three unprecedented carbon skeletons with highly rigid ring systems, were isolated from Cephalotaxus sinensis and structurally characterized by a combination of various methods. Compounds 1 and 2 are new skeletal norditerpenoid trilactones, while 3 and 4 are two norditerpenoids featuring different new carbon skeletons. Biosynthetic pathways for 1-4 were proposed by involving diverse and very fascinating chemical events with the coexisting cephalotane troponoids as the precursors. Compound 1 exhibited good NF-κB inhibition with an IC50 value of 4.12±0.61 µΜ.

Diterpenoids from Croton laui and their cytotoxic and antimicrobial activities.

Fourteen new diterpenoids including clerodane (1-12), labdane (13), and norlabdane (14) types, as well as nine known analogues were isolated from the aerial parts of Croton laui. Their structures were established on the basis of spectroscopic analysis, and that of crotonolide H (11) was confirmed by single-crystal X-ray crystallography. Crotonolide A (1) exhibited moderate cytotoxicity against two tumor cell lines, HL-60 (human premyelocytic leukemia, IC50 9.42 µM) and P-388 (murine leukemia, IC50 7.45 µM), and crotonolide G (10) displayed significant antibacterial activity against a panel of Gram-positive bacteria.

Trichinenlides A-T, mexicanolide-type limonoids from Trichilia sinensis.

Twenty new mexicanolide-type limonoids, namely, trichinenlides A-T (1-20), and 11 known analogues were isolated from the leaves and twigs of Trichilia sinensis. Trichinenlides B (2) and C (3) and heytrijunolide D exhibited inhibition against lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophages with IC50 values of 2.85, 1.88, and 3.33 µM, respectively.

Potent HGF/c-Met axis inhibitors from Eucalyptus globulus: the coupling of phloroglucinol and sesquiterpenoid is essential for the activity.

Eucalyptin A (1), together with two known compounds 2 and 3 exhibiting potent inhibition on HGF/c-Met axis, was discovered from the fruits of Eucalyptus globulus. 1 possessed an unprecedented carbon framework of phloroglucinol-coupled sesquiterpenoid, and its structure was elucidated by spectroscopic method and ECD calculation. A brief structure-activity relationship discussion indicated that the coupling of a phloroglucinol and a sesquiterpenoid is essential for the activity.