Pestalotiopamide E,a new amide from the endophytic fungus Pestalotiopsis sp.

Chemical examination of the endophytic fungus Pestalotiopsis sp., isolated from the leaves of the Chinese mangrove Rhizophora mucronata, yielded a new amide called pestalotiopamide E (1). The structure of the new compound was unambiguously elucidated on the basis of extensive spectroscopic data analysis.     

A new α-pyrone from the deep-sea actinomycete Nocardiopsis dassonvillei subsp. dassonvillei DSM 43111(T)

A new α-pyrone, nocapyrone S (1), together with five known compounds (2-6), were isolated from the deep-sea actinomycete Nocardiopsis dassonvillei subsp. dassonvillei DSM 43111(T). Their structures were determined by spectroscopic analyses. The absolute configuration of 1 was established by quantum approaches. Cytotoxic activity of 1 was evaluated against K562, MCF-7, SGC7901, A375, Hela, and HepG2 cell lines.     

西藏杓兰中两个新菲醌类化合物的分离与结构鉴定

目的研究西藏杓兰的化学成分。方法用硅胶柱色谱反复进行分离和Sephadex LH-20纯化，并通过波谱分析方法鉴定化合物结构。结果从乙酸乙酯部位分离得到两个菲醌类化合物：西藏杓兰醌A 和西藏杓兰醌B。鉴定其结构为：7-羟基-2-甲氧基-1,4-菲醌（1）；7-羟基-2,10-二甲氧基-1,4-菲醌（2）。结论西藏杓兰醌A 和西藏杓兰醌B均为新的菲醌类化合物。     

抗生素9792A和B的分离与结构鉴定及抗结核活性研究

在筛选新型抗结核抗生素过程中,对一株阳性链霉菌9792的发酵产物进行了分离纯化,获得了两个活性组分9792A和B.经光谱分析,确定9792A为pimprinethine,9792B为pimprinine.9792A和B抗结核分枝杆菌H37Rv的MIC分别为32μg/mL和16μg/mL,其确切抗结核活性属首次报道.     

Contribution of momilactones A and B to diabetes inhibitory potential of rice bran: Evidence from in vitro assays

This study was the first to detect the presence of the two compounds momilactone A (MA) and momilactone B (MB) in rice bran using liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). By in vitro assays, both MA and MB exhibited potent inhibitory activities on pancreatic α-amylase and α-glucosidase which were significantly higher than γ-oryzanol, a well-known diabetes inhibitor. Remarkably, MA and MB indicated an effective inhibition on trypsin with the IC₅₀ values of 921.55 and 884.03 µg/mL, respectively. By high-performance liquid chromatography (HPLC), quantities of MA (6.65 µg/g dry weight) and MB (6.24 µg/g dry weight) in rice bran were determined. Findings of this study revealed the α-amylase, α-glucosidase and trypsin inhibitors MA and MB contributed an active role to the diabetes inhibitory potential of rice bran.     

微生物来源的黑色素生物合成抑制剂H7264 A和B的分离和鉴别

利用直接抑制产黑色素菌株产生黑色素的方法，从链霉素sp.H7264的次生代谢产物中分离到两个黑色素生物合成抑制剂H7264 A和B，经理化性质和光谱分析，它们与Enopeptin A和B同质。     

Epigenetic modifiers alter the secondary metabolite composition of a plant endophytic fungus,Pestalotiopsis crassiuscula obtained from the leaves of Fragaria chiloensis

The addition of the DNA methyltransferase inhibitor 500 μM 5-azacytidine to the culture medium of a plant endophytic fungus, Pestalotiopsis crassiuscula, obtained from the leaves of Fragaria chiloensis, dramatically altered the profiles of its metabolites and resulted in the isolation of one new coumarin (1), along with six known compounds (2–7). HPLC profiles revealed that only compounds 3, 4, and 7 belonged to the new induced secondary metabolites. The structures of all isolated compounds were elucidated on the basis of extensive analysis of NMR spectra.     

Rhobupcyanoside B,A new cyanoside from Rhodiola bupleuroides

One new cyanoside, rhobupcyanoside B (1), together with 7 known ones, was isolated from the 70% ethanol extract of the roots and rhizomes of Rhodiola bupleuroides. Their structures were determined by spectroscopic methods, including 2D NMR techniques. Compound 1 was evaluated for its inhibitory activity against α-glucosidase with IC₅₀ value of 278.28 ± 0.55 μM by comparing with the positive control (acarbose) at 210.40 ± 0.32 μM.     

Salvicins A and B,new lignans from Salvia santolinifolia

Phytochemical investigation on the CHCl₃ soluble fraction of the ethanolic extract from the whole plants of Salvia santolinifolia led to two new lignans salvicins A (1) and B (2). Their structures were elucidated on the basis of spectral data.     

Pervosides A and B,new isoferulyl glucosides from Perovskia atriplicifolia

Pervosides A (1) and B (2), two new isoferulyl glucosides, have been isolated from the ethyl acetate soluble fraction of Perovskia atriplicifolia and their structures have been assigned on the basis of spectroscopic data. 3-Hydroxyestragole β-d-glucopyranoside (3) has also been isolated and characterized for the first time from this species.     

Japonicins A and B from the flowers of Inula japonica

Two new flavonols japonicins, A (1) and B (2), along with nine known flavonoids were isolated from an antidepressant fraction, which was separated from the 70% alcohol extract of the flowers of Inula japonica Thumb. The structures of compounds 1 and 2 were determined as 3,3′,4′,5,9,10-hexahydroxy-12-methylchroman[2,3-h]flavone and 8-(1-(3,4-dihydroxyphenyl)ethyl)-3,3′,4′,5,7-pentahydroxyflavone by the analyses of physical constants and spectral data. The special flavonoid structure having the substituent 1-phenylethyl at C-8 position was discovered for the first time.     

Japonicins A and B from the flowers of Inula japonica

Two new flavonols japonicins, A (1) and B (2), along with nine known flavonoids were isolated from an antidepressant fraction, which was separated from the 70% alcohol extract of the flowers of Inula japonica Thumb. The structures of compounds 1 and 2 were determined as 3,3',4',5,9,10-hexahydroxy-12-methylchroman[2,3-h]flavone and 8-(1-(3,4-dihydroxyphenyl)ethyl)-3,3',4',5,7-pentahydroxyflavone by the analyses of physical constants and spectral data. The special flavonoid structure having the substituent 1-phenylethyl at C-8 position was discovered for the first time.     

银杏叶提取物中银杏内酯A、B、C和白果内酯的提取、分离和结构鉴定

用柱层析结合溶剂法,从银杏叶提取物(EGb)中一次分得银杏内酯A、B、C和白果内酯BB.其结构经IR、1HNMR、13CNMR、MS等波谱确证,纯度经HPLC检测均为单一峰.     

银杏叶提取物中银杏内酯A、B、C和白果内酯的提取、分离和结构鉴定

采用柱层析结合溶剂法,从银杏叶提取物（EGb)中一次分得银杏内酯A、B、C和白果内酯BB。其结构经IR、^1HNMR、^13CNMR、MS等波谱确证,纯度经HPLC检测均为单一峰。     

云南甘草皂甙A和B结构鉴定

从云南甘草中分出２个新皂甙。根据理化性质和光谱数据，鉴定这两个新皂甙为：３β－羟基齐墩果－１１，１３－二烯－２９－羧酸－３－Ｏ－β－Ｄ－吡喃葡萄糖醛酸基（１→４）β－Ｄ－吡喃葡萄糖醛酸甙和３β，２１α－二羟基齐墩果－１１，１３二烯－２９－羧酸－３－Ｏ－β－Ｄ－吡喃葡萄糖醛酸基（１→４）β－Ｄ－吡喃葡萄糖醛酸甙，分别命名为：云南甘草皂甙Ａ和Ｂ。     

Two new diterpenoid alkaloids, beiwusines A and B, from Aconitum kusnezoffii

Two new atisine-type diterpenoid alkaloids, beiwusine A (1) and B (2), have been isolated from the roots of Aconitum kusnezoffii Reichb. Their structures were established on the basis of spectroscopic data. Beiwusines A and B are the first examples of atisine-type diterpenoid alkaloids having a hydroxyl group at C-1. In addition, one known diterpenoid alkaloid spiramine H (3) has been isolated.     

Asparosides A and B,two new steroidal saponins from Asparagus meioclados

Asparosides A ( 1 ) and B ( 2 ), two new saponins, were isolated from the roots of Asparagus meioclados . On the basis of chemical and spectroscopic evidence, their structures were elucidated as 23- O - f -arabinopyranosyl-(5 g ,25s)-spirostan-3 g ,23 f -diol-3- O -[ g - d -xylopyranosyl(1 M 4)]- g - d -glucopyranoside and 26- O - g -glucopyranosyl-5 g -furost-20(22)-ene-3 g ,26-diol-3- O -[ g - d -xylopyranosyl(1 M 4)]- g - d -glucopyranoside, respectively.     

Structural determination of crotamides A and B,the new amides from Croton sparsiflorus

Two new amides crotamides A and B, have been isolated from the n-hexane soluble fraction of Croton sparsiflorus in addition to salisomide and N-(4-hydroxyphenethyl)-octacosanamide reported for the first time from this species. Their structures were assigned from spectral data including 1D and 2D NMR spectroscopic data.