Structure elucidation of four prenylindole derivatives from Streptomyces sp. isolated from Ailuropoda melanoleuca feces

Abstract

Four new prenylindole derivatives, (R)-6-(2,3-dihydroxy-3-methylbutyl)indole (1), (R)-6-(2,3-dihydroxy-3-methylbutyl)indolin-2-one (2), and an unseparated mixture of (Z)-6-(4-hydroxy-3-methylbut-2-en-1-yl)indolin-2-one (3a) and (E)-6-(4-hydroxy-3-methylbut-2-en-1-yl)indolin-2-one (3b) with a ratio of 3 : 2, were isolated from the culture broth of a streptomycete isolated from Ailuropoda melanoleuca feces. Their structures were elucidated on the basis of 1D and 2D NMR spectroscopic techniques. The absolute configuration of 1 was determined by Mosher's method.