Seven new pentasaccharides from the roots of Rehmannia glutinosa.

Seven new pentasaccharides (1-7), rehmaglupentasaccharides A-G, were isolated from the air-dried roots of Rehmannia glutinosa. Their structures were established from the spectroscopic data obtained and by chemical evidence. The known verbascose (8) and stachyose (9) were also obtained in the current investigation, and the structure of stachyose was unequivocally defined using X-ray diffraction data. Compounds 1-9 were tested for their cytotoxicity against five human tumor cell lines, influence on dopamine receptor activation, and proliferation effects against Lactobacillus reuteri.

Two new baccharane triterpenes isolated from Rhus chinensis.

Two new baccharane triterpenes, 17,24-epoxy-23-en-baccharan-3-one (1) and 17,24(S)-epoxy-25-en-21-hydroxy-baccharan-3-one (2) were isolated from Rhus chinensis Mill. The structures were established on the basis of UV, IR, HR-ESI-MS, 1D and 2D NMR spectroscopy and X-ray diffraction analysis.

Four new iridoid glycosides from the roots of Rehmannia glutinosa.

Four new iridoid glycosides (1-4), rehmaglutosides L-O, were isolated from the air-dried roots of Rehmannia glutinosa. Their structures were established from the spectroscopic data obtained and by chemical evidence. The known mellittoside (5) and ajugol (6) were also obtained in the current investigation, and the structure of mellittoside was unequivocally defined using X-ray diffraction data. Compounds 1-6 were tested for their cytotoxicity against five human tumor cell lines and proliferation effects on Lactobacillus Reuteri.

Four sesquiterpenes isolated from Taraxacum mongolicum.

One new sesquiterpene, (6S,7R,11S)-13-carboxy-1(10)-en-dihydroartemisinic acid (1), together with three known sesquiterpenes, ainsliaea acid B (2), mongolicumin B (3), and 11ß,13-dihydroxydeacetylmatricarin (4) were isolated from Taraxacum mongolicum Hand.-Mazz. The structures were established on the basis of UV, IR, HR-ESI-MS, 1D and 2D NMR spectroscopy, ECD spectroscopy, and X-ray diffraction analysis. Compound 1 was found to have potential anti-inflammatory activity and could reduce LPS-induced NO levels in murine macrophage, with inhibitory rate of 37%.

Three new pyridine alkaloids and one new iridoid analogue from the leaves of Rehmannia glutinosa.

As part of an ongoing project on Rehmannia species, three new pyridine alkaloides (glutinosines A - C), and one new iridoid analogue (rehmaglutin E), were isolated from the leaves of Rehmannia glutinosa. The structures of the new compounds were established by extensive spectroscopic analysis and electronic circular dichroism calculations.

Four ionones and ionone glycosides from the whole plant of Rehmannia piasezkii.

Four new ionones and ionone glycosides (1-4) were isolated from the whole plant of Rehmannia piasezkii Maxim. Their planar structures as well as absolute configuration were confirmed via spectroscopic analysis, ECD calculation, and X-ray crystallography. Compounds 1-4 were tested for their cytotoxicity against five human tumor cell lines and ability to inhibit LPS-activated NO production in the BV2 cell line.

Two new sesquiterpene dimers isolated from the roots of Saussurea lappa (Yunmuxiang).

Two new sesquiterpene dimers, lappadimers A and B, were isolated from the roots of Saussurea lappa (Yunmuxiang). Their structures were established on the basis of spectroscopic methods. They were found to have potential anti-inflammatory activity at 10 µM and could reduce LPS-induced NO levels in murine macrophage, with inhibitory rates of 67% and 47%, respectively.

[Advances in studies on structure and pharmacological activities of natural tirucallane-type triterpenoids].

The tirucallane-type triterpenoids, composed of six isoprene units, belong to a group of tetracyclic triterpenoids. Although the naturally-derived tirucallane-type triterpenoids were found in a small amount, the kind of compounds showed various structures, which consist of apo-type, linear said-chain-type and cyclolike said-chain-type and broad bioactivities, such as cytotoxicity, anti-inflammation, antioxidation and anti-plasmin, etc. This paper summarized origins, structures and bioactivities of tirucallane-type triterpenoids in recent ten years. The future research and exploration of tirucallane-type triterpenoids were discussed and prospected.

Ganoderic acid A protects neural cells against NO stress injury in vitro via stimulating ß adrenergic receptors.

Excessive nitric oxide (NO) causes extensive damage to the nervous system, and the adrenergic system is disordered in many neuropsychiatric diseases. However, the role of the adrenergic system in protection of the nervous system against sodium nitroprusside (SNP) injury remains unclear. In this study, we investigated the effect of ganoderic acid A (GA A) against SNP injury in neural cells and the role of adrenergic receptors in GA A neuroprotection. We found that SNP (0.125-2 mM) dose-dependently decreased the viability of both SH-SY5Y and PC12 cells and markedly increased NO contents. Pretreatment with GA A (10 µM) significantly attenuated SNP-induced cytotoxicity and NO increase in SH-SY5Y cells, but not in PC12 cells. Furthermore, pretreatment with GA A caused significantly higher adrenaline content in SH-SY5Y cells than in PC12 cells. In order to elucidate the mechanism of GA A-protecting SH-SY5Y cells, we added adrenaline, phentolamine, metoprolol, or ICI 118551 1 h before GA A was added to the culture medium. We found that addition of adrenaline (10 µM) significantly improved GA A protection in PC12 cells. The addition of ß1-adrenergic receptor antagonist metoprolol (10 µM) or ß2-adrenergic receptor antagonist ICI 118551 (0.1 µM) blocked the protective effect of GA A, whereas the addition of α-adrenergic receptor antagonist phentolamine (0.1 µM) did not affect GA A protection in SH-SY5Y cells. These results suggest that ß-adrenergic receptors play an important role in the protection of GA A in SH-SY5Y cells against SNP injuries, and excessive adrenaline system activation caused great damage to the nervous system.

[Reviews on natural monocyclic sesquiterpenoids and their bioactivities].

Sesquiterpenes are a class of terpenoids composed of three isoprene units( 15 carbons). Sesquiterpenoids possess a variety of different structures,including acyclic sesquiterpenes,monocyclic sesquiterpenoids,bicyclic sesquiterpenoids,tricyclic sesquiterpenoids,tetracyclic sesquiterpenoids and macrocyclic sesquiterpenoids. Among them,a large number of monocyclic sesquiterpenoids were isolated and display extensive bioactivities,such as cytotoxic,antioxidant,anti-inflammatory,antibacterial and other activities. In this review,we summarized the progress about the phytochemistry and biological activities of monocyclic sesquiterpenoids( a total of161 compounds) reported from 2014 to 2018( 5 years),including megastigmanes,monocyclofarnesol-type,bisabolane-type,germacrane-type,and other types of monocyclic sesquiterpenoids. Furthermore,several future research perspectives and development of sesquiterpenoids as potential therapeutic agents were discussed as well.

Five new iridoids from the whole plants of Rehmannia henryi.

Five new iridoids (1-5), jiohenrins A-E, together with sixteen known compounds (6-21), were isolated from the whole plants of Rehmannia henryi. The structures of these compounds were elucidated on the basis of their spectroscopic data.

Rearranged iridal-type triterpenoids from Iris tectorum.

Three new iridal-type triterpenoids (1-3) featuring a rearranged homofarnesylside chain were isolated from the rhizomes of Iris tectorum. Compounds 2 and 3 were found to be a pair of epimers. Their structures were elucidated on the basis of comprehensive spectroscopic analysis. A possible biosynthetic pathway for them was postulated. Moreover, the mixture of compounds 2 and 3 exhibited moderate neuroprotective activity against serum deprivation-induced PC12 cell death.

Nine new compounds from the whole plants of Rehmannia henryi.

Eight new iridoids (1-8) and an ionone glucoside (9), together with 31 known compounds (10-40), were isolated from the whole plants of Rehmannia henryi. The structures of these compounds were elucidated on the basis of their spectroscopic data and chemical evidence.

[Reviews on natural naphthoquinones and their bioactivities].

The naphthaquinones are widely distributed in plants. They are usually in higher plants, but a few of them were also found in microorganisms. There is a lot of research showing that they had multiple pharmaco-activities such as cytotoxic, antioxidant, anti-inflammatory and antibacterial activities, etc. In recent years, they have attracted extensive attention at home and abroad especially in terms of the anti-tumor activity. For further research, 69 new natural naphthoquinones reported in the last five years (2013-2017) were reviewed. They were divided into five major types: simple 1,4-naphthoquinones, furan and pyran naphthoquinones, 1,2-naphthoquinones, naphthohydroquinones and naphthoquinone polymers, which showed cytotoxic, antioxidative, anti-inflammatory and antibacterial biological activities, et al. The research of these compounds in the future was also proposed.

A Chemical Investigation of the Leaves of Morus alba L.

The leaves of Morus alba L. are an important herbal medicine in Asia. The systematic isolation of the metabolites of the leaves of Morus alba L. was achieved using a combination of liquid chromatography techniques. The structures were elucidated by spectroscopic data analysis and the absolute configuration was determined based on electronic circular dichroism (ECD) spectroscopic data and hydrolysis experiments. Their biological activity was evaluated using different biological assays, such as the assessment of their capacity to inhibit the aldose reductase enzyme; the determination of their cytotoxic activity and the evaluation of their neuroprotective effects against the deprivation of serum or against the presence of nicouline. Chemical investigation of the leaves of Morus alba L. resulted in four new structures 1⁻4 and a known molecule 5. Compounds 2 and 5 inhibited aldose reductase with IC50 values of 4.33 µM and 6.0 µM compared with the potent AR inhibitor epalrestat (IC50 1.88 × 10−3 µM). Pretreatment with compound 3 decreased PC12 cell apoptosis subsequent serum deprivation condition and pretreatment with compound 5 decreased nicouline-induced PC12 cell apoptosis as compared with control cells (p < 0.001).

[Constituents isolated from n-butanol extract of leaves of Moringa oleifera].

Seventeen compounds were isolated from n-butanol extract of the leaves of Moringa oleifera, using column chromatography over macroporous resin HP-20,Sephadex LH-20, and ODS. Their structures were identified as two carboline,tangutorid E(1) and tangutorid F(2); three phenolic glycosides,niazirin(3)，benzaldehyde 4-O-α-L-rhamnopyranoside(4) and 4-O-ß-D-glucopyranosidebenzoic acid(5); four chlorogenic acid and derivatives,4-caffeoylquinic acid(6),methyl 4-caffeoylquinate(7),caffeoylquinic acid(8) and methyl caffeoylquinate(9); two nucleosids,uridine(10) and adenosine(11); one flavone,quercetin 3-O-ß-D-glucopyranoside(12); five other types of compounds,phthalimidineacetic acid(13),3-pyridinecarboxamide(14),3,4-dihydroxy-benzoic acid(15),5-hydroxymethyl-2-furancarboxylic acid(16) and 5-hydroxymethyl-2-furaldehyde(17) by the spectral data of ¹H, ¹³C-NMR and MS. Among them,compounds 1-2,7,9-10,16 and 17 were isolated from M. oleifera for the first time.

[Anti-tumor target prediction and activity verification of Ganoderma lucidum triterpenoids].

It has reported that Ganoderma lucidum triterpenoids had anti-tumor activity. However, the anti-tumor target is still unclear. The present study was designed to investigate the anti-tumor activity of G. lucidum triterpenoids on different tumor cells, and predict their potential targets by virtual screening. In this experiment, molecular docking was used to simulate the interactions of 26 triterpenoids isolated from G. lucidum and 11 target proteins by LibDock module of Discovery Studio2016 software, then the anti-tumor targets of triterpenoids were predicted. In addition, the in vitro anti-tumor effects of triterpenoids were evaluated by MTT assay by determining the inhibition of proliferation in 5 tumor cell lines. The docking results showed that the poses were greater than five, and Libdock Scores higher than 100, which can be used to determine whether compounds were activity. Eight triterpenoids might have anti-tumor activity as a result of good docking, five of which had multiple targets. MTT experiments demonstrated that the ganoderic acid Y had a certain inhibitory activity on lung cancer cell H460, with IC50 of 22.4 µmol•L ⁻¹, followed by 7-oxo-ganoderic acid Z2, with IC50 of 43.1 µmol•L ⁻¹. However, the other triterpenoids had no anti-tumor activity in the detected tumor cell lines. Taking together, molecular docking approach established here can be used for preliminary screening of anti-tumor activity of G.lucidum ingredients. Through this screening method, combined with the MTT assay, we can conclude that ganoderic acid Y had antitumor activity, especially anti-lung cancer, and 7-oxo-ganoderic acid Z2 as well as ganoderon B, to a certain extent, had anti-tumor activity. These findings can provide basis for the development of anti-tumor drugs. However, the anti-tumor mechanisms need to be further studied.

Three new triterpenoids from Ganoderma theaecolum.

Three new triterpenoids (1-3), together with four known triterpenoids (4-7), were isolated from the fruiting bodies of Ganoderma theaecolum. Their structures were elucidated on the basis of their spectroscopic data and chemical evidence. Compounds 4 and 6 exhibited antitumor activities against H460 cells with IC50 values of 22.4 and 43.1 µM, respectively. And the cytotoxic activities of compounds 4 and 5 against MDA-MB-231 cancer cell lines were assayed with IC50 values of 49.1 and 75.8 µM, respectively.

Aristolochic acid derivatives from the rhizome of Arisolochia championii.

Four new aristolochic acid derivatives aristchamic A (1), aristchamic B (2), aristochamic C (3a), aristchamic D (3b) and one new aristolactam aristolactam-CV (4), together with 10 known compounds (5-14), were isolated from the rhizomes of Aristolochia championii. Their structures were assigned by detailed analysis of MS and NMR spectroscopic data. All of the isolated compounds were evaluated for their cytotoxic activities against HCT-116, HepG2, BGC-823, NCI-H1650, and A2780 cell. Compound 1 exhibited significant cytotoxic activity against HCT-116, HepG2, BGC-823, and NCI-H1650, with IC50 values of 0.50, 7.37, 2.66, and 0.75µM, respectively.

Apocynin derivatives from Iris tectorum.

Phytochemical investigation of the rhizomes of Iris tectorum resulted in the isolation and characterization of three new apocynin derivatives, apocynin-4-O-ß-D-(6'-O-syringyl)glucopyranoside (1), scrophenoside C-7-ethyl ether (2, 3), together with a new naturally occurring compound but known by synthesis, apocynin-4-O-ß-D-xylopyranoside (4), and five known ones (5-9). Their structures were elucidated on the basis of spectroscopic data interpretation.