Indolediketopiperazine Alkaloids from Eurotium cristatum EN-220, an Endophytic Fungus Isolated from the Marine Alga Sargassum thunbergii.

ABSTRACT: Four new indolediketopiperazine derivatives (1-4), along with nine known congeners (5-13), were isolated and identified from the culture extract of Eurotium cristatum EN-220, an endophytic fungus obtained from the marine alga Sargassum thunbergii. The structures of thesecompounds were elucidated on the basis of extensive spectroscopic analysis and the absolute configurations of compounds 1-4 were established by NOESY experiments and by chiral HPLC analyses of their acid hydrolysates. The absolute configuration of C-8 (a quaternary carbon substituted with a hydroxyl group) in 5 of preechinulin class was firstly determined by electronic circular dichroism (ECD) calculations. All these compounds were evaluatedfor brine shrimp (

SUBMITTER: Du FY 

PROVIDER: S-EPMC5334605 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature