Hyperxylones A and B, two polycyclic polyprenylated acylphloroglucinols with a benzoyl substituted bicyclo[3.2.1]octane core from Hypericum beanii

Abstract

Two new polycyclic polyprenylated acylphloroglucinols (PPAPs) possessing a rare benzoyl substituted bicyclo[3.2.1]octane core, hyperxylones A (1) and B (2), along with three new dearomatized isoprenylated acylphloroglucinols (DIAPs), hyperxylones C − E (3–5), were isolated from the roots of Hypericum beanii. The structures of 1–5 were determined by high-resolution electrospray ionization mass spectroscopy (HRESIMS) and 1D/2D nuclear magnetic resonance (NMR) spectroscopic analyses, gauge-independent atomic orbital (GIAO) NMR calculations, and electronic circular dichroism (ECD) calculations. Compounds 1 and 2 were biomimetically semi-synthesized starting from 5 and 4, respectively, enabling the correct stereochemical assignment of 5 and 4. Moreover, compounds 1 and 2 showed anti-nonalcoholic steatohepatitis (NASH) activity by inhibiting lipid deposition in L02 cells; compounds 3 and 5 exhibited nitric oxide (NO) inhibitory activity in lipopolysaccharides (LPS)-induced RAW264.7 cells.