A new cyclic nonapeptide, amanexitide (1), along with the known cyclopeptides, a- and b-amanitins, was isolated from the fruiting bodies of Amanita exitialis, a newly described poisonous mushroom endemic to Guangzhou,...A new cyclic nonapeptide, amanexitide (1), along with the known cyclopeptides, a- and b-amanitins, was isolated from the fruiting bodies of Amanita exitialis, a newly described poisonous mushroom endemic to Guangzhou, Guangdong Province, China. Its amino acid composition and absolute configuration were determined by chemical degradation and derivatization followed by chiral GC analysis. Its amino acid sequence was elucidated by extensive analysis of ESIMS/MS and FTICRMS data. The occurrence of 1 in this mushroom is interesting because it has a structure closely related to antamanide, a cyclic decapeptide with antidote activity against amatoxins and phallotoxins, occurring in A. phalloides.展开更多
Eight new diarylheptanoids,coriandralpinins A-H(1-8),were isolated from the rhizomes of Alpinia coriandriodora,an edible plant of the ginger family.Their structures,including the absolute configurations,were establish...Eight new diarylheptanoids,coriandralpinins A-H(1-8),were isolated from the rhizomes of Alpinia coriandriodora,an edible plant of the ginger family.Their structures,including the absolute configurations,were established by extensive spectroscopic analysis and ECD calculations.Compounds 1-8 have a 1,5-O-bridged diarylheptanoid structure featuring polyoxygenated aryl units.When evaluated for intracellular antioxidant activity using t-BHP stressed RAW264.7 mac-rophages,all these compounds scavenged reactive oxygen species(ROS)in a concentration-dependent manner.Compounds 3 and 5 also showed inhibitory activity against NO release in LPS-induced RAW 264.7 cells.Six known flavonols,7,4′-di-O-methylkaempferol,7-O-methylquercetin,7,4′-di-O-methylquercetin,7,3′,4′-tri-O-methylquercetin,kaempferol 3-O-β-d-(6-O-α-l-rhamnopyranosyl)glucopyranoside,and 3-O-β-d-glucopyranuronosylquercetin were also isolated and characterized from the rhizomes.展开更多
基金This work was supported by the Knowledge Innovation Program of the Chinese Academy of Sciences(No.KSCX2-YW-N-036).
文摘A new cyclic nonapeptide, amanexitide (1), along with the known cyclopeptides, a- and b-amanitins, was isolated from the fruiting bodies of Amanita exitialis, a newly described poisonous mushroom endemic to Guangzhou, Guangdong Province, China. Its amino acid composition and absolute configuration were determined by chemical degradation and derivatization followed by chiral GC analysis. Its amino acid sequence was elucidated by extensive analysis of ESIMS/MS and FTICRMS data. The occurrence of 1 in this mushroom is interesting because it has a structure closely related to antamanide, a cyclic decapeptide with antidote activity against amatoxins and phallotoxins, occurring in A. phalloides.
基金supported by NSFC Grants(Nos.81172942 and 81872773).
文摘Eight new diarylheptanoids,coriandralpinins A-H(1-8),were isolated from the rhizomes of Alpinia coriandriodora,an edible plant of the ginger family.Their structures,including the absolute configurations,were established by extensive spectroscopic analysis and ECD calculations.Compounds 1-8 have a 1,5-O-bridged diarylheptanoid structure featuring polyoxygenated aryl units.When evaluated for intracellular antioxidant activity using t-BHP stressed RAW264.7 mac-rophages,all these compounds scavenged reactive oxygen species(ROS)in a concentration-dependent manner.Compounds 3 and 5 also showed inhibitory activity against NO release in LPS-induced RAW 264.7 cells.Six known flavonols,7,4′-di-O-methylkaempferol,7-O-methylquercetin,7,4′-di-O-methylquercetin,7,3′,4′-tri-O-methylquercetin,kaempferol 3-O-β-d-(6-O-α-l-rhamnopyranosyl)glucopyranoside,and 3-O-β-d-glucopyranuronosylquercetin were also isolated and characterized from the rhizomes.