Isatindolignanoside A, a glucosidic indole-lignan conjugate from an aqueous extract of the Isatis indigotica roots

摘要

A glucosidic indole-lignan conjugate with a novel carbon skeleton, named isatindolignanoside A(1), was isolated from an aqueous extract of the Isatis indigotica roots "ban lan gen". Its structure was elucidated by comprehensive analysis of spectroscopic data, including J-and NOESY correlation-based configurational analysis, circular dichroism(CD) data, enzyme hydrolysis, and theoretical ECD calculation. In a preliminary assay, compound 1 showed antiviral activity against Coxsackie virus B3. This compound is the first example of natural product having a structural feature of conjugation between indole and lignan units, and its biosynthetic pathway is postulated.