A New Furostanol Saponin from Dioscorea futshauensis

A new furostanol saponin presenting moderate bioacitivity of inducting morphological deformation of Pyricularia oryzae mycelia was isolated from Dioscorea futshauensis R.Kunth by bioacitivity-guided fractionation. The structure was established as 26-O-β-D-glucopyranosyl-3β,26-diol-23(S)-methoxyl-(25R)-furost-5,20(22)-diene-3-O-[α-L-rhamnopyranosyl(1→2)-β-D-glucopyranosyl(1→3)]-β-D-glucopyranoside on the basis of chemical evidencesand spectral analysis,especially by 2D-NMR techniques.     

Two New Steroidal Glycosides from Liriope muscari

Liriope muscari (Decn.) Bailey (Liliaceae) is a folk medicinal plant used as a substitute of Ophiopogon japonicus (Thunb.) Ker-Gawl., mainly distributing in Quanzhou, Fujian Province, China1. Previously, we reported the isolation and identification of two…     

A new enzyme catalysis: 3,4-dioxidation of some aryl β-d-glycopyranosides by fungal pyranose dehydrogenase

Quinone-dependent pyranose dehydrogenase presents a new tool for versatile conversions of numerous carbohydrates to their di- and tricarbonyl derivatives. This enzyme purified from the basidiomycete Agaricus meleagris catalysed dioxidation of several aromatic β-d-glucopyranosides and a β-d-xylopyranoside into the corresponding 3,4-didehydro-β-d-aldopyranosides (β-d-aldopyranosid-3,4-diuloses) in high yields, typically >80% for 4-nitrophenyl glycosides. These new compounds were doubly hydrated in aqueous solution. According to in situ NMR investigations, the reaction intermediates were the corresponding 3- and 4-dehydro compounds. The analogous anomeric α-glycosides underwent one-step oxidation only at C-3 to 3-dehydro-α-d-aldopyranosides (α-d-pyranosid-3-uloses).     

石香薷中两个新黄酮甙的研究

石香薷中两个新黄酮甙的研究郑尚珍，孙丽萍，沈序维王毅（西北师范大学化学系，兰州，７３００７０）（中国科学院兰州化学物理研究所）关键词石香薷，唇形科，黄酮甙唇形科植物石香薷（ＭＯｓｌａｃｈｉｎｅｎｓｉｓＭａｘｉｍ）作为中药，用来治疗暑湿感冒、头痛、腹痛...     

Triterpene Glycosides from Plants of the Astragalus Genus. Structure of Cyclounifolioside A from Astragalus unifoliolatus

The known compound oleanolic acid (1) and a new cycloartane glycoside cyclounifolioside A (2), which has the structure 6,16-di-O-acetyl-24R-cycloartan-6,16,24,25-pentaol 3-O--D-glucopyranoside, were isolated from Astragalus unifoliolatus Bunge. The structures of the isolated compounds were established using chemical transformations and two-dimensional spectra (TOCSY, ROESY, HMBC, HSQC, COSY).     

A new triterpene glycoside from sea cucumber Holothuria leucospilota

A new triterpene glycoside, leucospilotaside A, along with a known saponin, isolated from sea cucumber Holothuria leucospilota, and its structure was elucidated as 3β-O-[4-O-sodiumsulfate-β-D-quinovopyranosyl-(1→2)-β-D-xylopyranosyl]-holosta-22-ketone-9-en-17α,25α-diol (1) by extensive spectroscopic analysis and chemical methods. Leucospilotaside A (1) has a ketone carbonyl group (22) in the aglycon side chain.     

A phenolic glycoside from Fagopyrum dibotrys (D.Don) Hara

A new phenolic constituent along with five known compounds were isolated from Fagopyrum dibotrys(D.Don)Hara.The new compound was characterized as 1,3-dimethoxy-2-O-β-xylo-pyranosyl-5-O-β-glucopyranosyl-benzene,by spectroscopic analysis and enzymatic hydrolysis.     

A new aromatic glycoside and its anti-proliferative activities from the leaves of Bergenia purpurascens

Chemical investigation of the ethanolic extracts of the dried leaves of Bergenia purpurascens led to the isolation and identification of a new aromatic glycoside, 1-O-β-D-glucopyranosyl-2-methoxy-3-hydroxyl-phenylethene (1), along with other 19 known compounds (2–20). The structure of compound 1 was determined by a detailed analysis using various analytical techniques, including 1D and 2D NMR. In vitro anti-proliferative activities of compound 1 on five human cancer cell lines were evaluated. The results showed that compound 1 possessed the most potent effects with the IC₅₀ values of 14.36 ± 1.04 μM against T24 cells. The further bioactivity analysis showed that compound 1 induced apoptosis of T24 cells, and altered anti- and pro-apoptotic proteins, leading to mitochondrial dysfunction and activation of caspase-3 for causing cell apoptosis. The present investigation illustrated compound 1 might be used as a potential antitumour chemotherapy candidate.     

Synthesis of Floridoside

Floridoside (2-O-glycerol-α-D-galactopyranoside) is a natural glycerol glycoside found in red algae and is believed to play important roles in carbon storage, transport, and assimilation and in the regulation of osmotic balance. We describe here a rapid, high-yield, and high-stereoselectivity synthesis of floridoside in which the key step involves the 1,2-cis O-glycosylation of 1,3-dibenzylglycerol with ethyl 2,3,4,6-tetra-O-benzyl-1-thio-β-D-galactopyranoside using iodonium dicollidine perchlorate (IDCP) or N-iodosuccinimide/trimethylsilyl triflate (NIS/TMSOTf) as promoters.