Hyperberins A and B, Type B Polycyclic Polyprenylated Acylphloroglucinols with Bicyclo[5.3.1]hendecane Core from <i>Hypericum beanii</i>

Abstract

The first examples of type B polycyclic polyprenylated acylphloroglucinols with a bicyclo[5.3.1]hendecane core, hyperberins A (<b>1</b>) and B (<b>2</b>), were isolated from <i>Hypericum beanii</i>, together with three biosynthetic congeners. Their structures were established by a combination of NMR, electric circular dichroism (ECD), and X-ray diffraction analyses. These isolates indicated divergent cationic cyclization as key steps in the biosynthesis of PPAPs with diverse architectures. Compounds <b>1</b> and <b>2</b> were moderately cytotoxic and exhibited significant anti-inflammatory activities.