Hyperuralones A and B, New Acylphloroglucinol Derivatives with Intricately Caged Cores from Hypericum uralum

Hyperuralone A (1), a polycyclic polyprenylated acylphloroglucinol possessing an unprecedented tetracyclo-[5.3.1.14,9.04,11]-dodecane core, was characterized from Hypericum uralum together with hyperuralone B (2), a congener with another complex caged skeleton. Their structures were determined by extensive spectroscopic analysis and ECD calculations. A plausible biosynthetic pathway of their intriguing architectures via intramolecular...