Hyperfols A and B: Two Highly Modified Polycyclic Polyprenylated Acylphloroglucinols from <i>Hypericum perforatum</i>

Abstract

Two novel polycyclic polyprenylated acylphloroglucinols (PPAPs), hyperfols A (<b>1</b>) and B (<b>2</b>), and two known biosynthetically related precursors (<b>3</b> and <b>4</b>) were isolated from <i>Hypericum perforatum</i>. Compound <b>1</b> possesses an unprecedented 2,3-<i>seco</i>-PPAP with a fused 5/5/9/5 tetracyclic skeleton, and <b>2</b> features a 30-norPPAP. Their structures were established by spectroscopic analysis, computer-assisted structure elucidation software, and electronic circular dichroism calculations. Moreover, compounds <b>1</b> and <b>4</b> exhibit significant cytotoxicity against human erythroleukemia cells by inducing cell apoptosis.