Yao Xin-sheng

Five new bidesmoside triterpenoid saponins from Stauntonia chinensis

Eleven triterpenoid saponins (1–11) were isolated from Stauntonia chinensis DC. (Lardizabalaceae), including five new compounds, yemuoside YM21–25 (1–3, 6, 7) structures of which were elucidated by chemical methods and a combination of MS, 1D‐ and 2D‐ NMR experiments including DEPT, 1H1H COSY, HSQC, HMBC, TOCSY, and NOESY as 3‐O‐α‐L‐arabinopyranosyl‐(1 → 3)‐[α‐L‐rhamnopyranosyl‐(1 → 2)‐]α‐L‐arabinopyranosyl‐akebonicacid‐28‐O‐α‐L‐rhamnopyranosyl‐(1 → 4)‐β‐D‐glucopyranosyl‐(1 → 6)‐β‐D‐glucopyranosyl ester (1), 3‐O‐β‐D‐xylopyranosyl‐(1 → 3)‐α‐L‐rhamnopyranosyl‐(1 → 2)‐α‐L‐arabinopyranosyl‐akebonic acid‐28‐O‐α‐L‐rhamnopyranosyl‐(1 → 4)‐β‐D‐glucopyranosyl‐(1 → 6)‐β‐D‐glucopyranosyl ester (2), 3‐O‐β‐D‐glucopyranosyl‐(1 → 3)‐α‐L‐arabinopyranosyl‐akebonic acid‐28‐O‐α‐L‐rhamnopyranosyl‐(1 → 4)‐β‐D‐glucopyranosyl‐(1 → 6)‐β‐D‐glucopyranosyl ester (3), 3‐O‐α‐L‐arabinopyranosyl‐(1 → 3)‐[α‐L‐rhamnopyranosyl‐(1 → 2)‐]α‐L‐arabinopyranosyl‐akebonic acid‐28‐O‐β‐D‐glucopyranosyl‐(1 → 6)‐β‐D‐glucopyranosyl ester (6), 3‐O‐α‐L‐arabinopyranosyl‐(1 → 3)‐[α‐L‐arabinopyranosyl‐(1 → 2)‐]α‐L‐arabinopyranosyl‐akebonic acid‐28‐O‐β‐D‐glucopyranosyl‐(1 → 6)‐β‐D‐glucopyranosyl ester (7). Copyright

Polyketides from a marine sponge-derived fungus Mycelia sterilia and proton–proton long-range coupling

A series of polyketide‐originated metabolites (1–5) were isolated from a marine sponge‐derived fungus Mycelia sterilia. Of these, 1–3 were new compounds. Their structures were elucidated by spectroscopic methods as (4R*, 5S*, 6S*, 8S*, 13R*)‐1‐(2,8‐dihydroxy‐1,2,6‐trimethyl‐1,2,6,7,8,8a‐hexahydro‐naphthalen‐1‐yl)‐3‐methoxy‐propan‐1‐one (1), 4,8‐dihydroxy‐7‐(2‐hydroxy‐ethyl)‐6‐methoxy‐3,4‐dihydro‐2H‐naphthalen‐1‐one (2) and 1‐methyl‐naphthalene‐2,6‐dicarboxylic acid (3). In 1, the proton–proton long‐range coupling phenomenon claimed attention and was discussed. Copyright

InCl 3 -mediated intramolecular Friedel-Crafts-type cyclization and its application to construct the [6-7-5-6] tetracyclic scaffold of liphagal

A unified strategy toward the construction of the [5.7.6]tricyclic skeleton of liphagal is reported, featuring InCl3-mediated intramolecular Friedel-Crafts-type cyclization.

Studies on the “Xiehuo” Effect and Compositions of Guangdong Herbal Tea

Abstract In recent years, people are concerned about the “xiehuo” effect of Guangdong Herbal Tea (GHT). Study results found that GHT not only elevated the decreased levels of neurotransmitters and reduced immunocompetence in restraint stressed mice, but also prevented stressed mice against liver injury and inflammation. We also noticed that GHT accelerated the utilization of sugar energy and improved the capability of lipid tolerance in stressed mice. These results indicated that the effect of GHT on “xiehuo” may be related to its anti-stress effects. The results of mechanism study showed that GHT had the effects of anti-stress by regulating RNS and ROS generation in cells of restrained mice, at the same time regulating the activities and gene expressions of the key enzymes in the free radical chain reaction. Therefore, the anti-stress mechanism of GHT was related, at least partly, to the protection effect against oxidative stress in stress-loaded organisms. The main compounds of GHT identified were Gallic acid, Protocatechuic acid, (+)-Catechin, 4-Hydroxybenzoic acid, Caffeic acid, Ellagic acid-4-O-xylopyranoside, Isoquercitrin, and Ellagic acid. Results showed that most of these compounds are the active ingredients that are responsible for the “xiehuo” effect of GHT.

Recent progress in the study of zeaxanthin dipalmitate

Wolfberry is a traditional “affinal drug and diet” in Chinese and Eastern cultures, which is thought to nourish the liver, kidneys, and eyes for over one thousand years. Modern scientific studies have proved that wolfberry and its derivatives could prevent and treat a variety of diseases of the liver, gut, retina, neuron, and kidneys. However, due to its nature of mixture of a large number of constituents, it is quite difficult to delineate the major effective constituent and therapeutic mechanism responsible for those beneficial effects. This review will briefly introduce the recent progress of the botanical characteristic, metabolism, structural classification and disease therapy of the major constituent—zeaxanthin dipalmitate (ZD)—and its derivatives from wolfberry carotenoids. In most published literatures, the health-promoting properties of wolfberry were investigated from Lycium barbarum polysaccharides, which were mixtures of mostly carbohydrates and a small part of pigments/proteins. Recently, we isolated wolfberry into 5 parts, including polysaccharides, lycibarbars- permidines, polyphenols, phenylpropionoyl phenylethylamine, and carotenoids. By using several disease screening models, we found that the carotenoid extract of wolfberry could, at least partly, represent its disease prevention and therapy functions. Since ZD was shown to be the major constituent (~81.5%–87.5%) in total carotenoids of wolfberry, we considered that ZD could be a representative constituent of wolfberry. Thus, we firstly investigated the molecular mechanisms for the storage, synthesis, and degradation of ZD and other carotenoids during Lycium barbarum growth. Then we isolated and characterized all 15 carotenoid constituents from wolfberry. It was found that free carotenoids were the main pigments of immature wolfberry while esterified carotenoids (e.g. ZD) consisted most of the pigment materials in mature fruit. Thirdly, we reviewed the protective effects and possible mechanisms of ZD and its derivatives on liver diseases (e.g. acute liver failure, alcoholic liver injury, non-alcoholic fatty liver disease and viral hepatitis), stem cell injury and transplantation, cardiovascular disorders, eye diseases, and other digestive system syndromes, including tumors. In addition, possible future research directions and contents of ZD will also be discussed, such as (i) can ZD represent most of the beneficial functions of wolfberry, or synergistic promoting effects are existed between ZD and other distinct constituents from wolfberry (e.g. lycibarbarspermidines or polyphenols)? (ii) what is the optimal consumption dosage of ZD in daily life and is there any adverse effect of this kind of carotenoids? (iii) what is the exact metabolic pathways and tissue distribution after ZD consumption? We strongly believe that delineation of those questions will definitive promote basic study, clinical application, and industrial development of wolfberry in the world.