1. Hyperforones A–C, benzoyl-migrated [5.3.1]-type polycyclic polyprenylated acylphloroglucinols from Hypericum forrestii
- Author
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Yi-Ran Li, Wei-Jia Lu, Xin Zhou, Yanqiu Zhang, Wen-Jun Xu, Ling-Yi Kong, Hao Zhang, Jun Luo, and Qi-Ji Li
- Subjects
Steric effects ,Circular dichroism ,biology ,Bicyclic molecule ,010405 organic chemistry ,Stereochemistry ,Organic Chemistry ,Hypericum forrestii ,Nuclear magnetic resonance spectroscopy ,010402 general chemistry ,biology.organism_classification ,01 natural sciences ,0104 chemical sciences ,Hyperforin ,chemistry.chemical_compound ,chemistry ,Chirality (chemistry) - Abstract
Three unprecedented benzoyl-migrated polycyclic polyprenylated acylphloroglucinols (PPAPs), hyperforones A–C (1–3), were isolated from Hypericum forrestii, together with a new benzoyl-substituted analogue (4) of hyperforin. Compounds 1–3 are the first examples of naturally occurring benzoyl-PPAPs with a unique C-1 H-substituted bicyclo[5.3.1]hendecane scaffold. Their structures and absolute configurations were established by HRESIMS, NMR spectroscopy data, electronic circular dichroism (ECD) exciton chirality method, ECD calculations, and gauge-independent atomic orbital (GIAO) NMR calculations with DP4+ analyses. A plausible biosynthetic formation of the benzoyl-migrated C-1 H-substituted bicyclo[5.3.1]hendecane skeleton in 1–3via a sterically favored hemiketalization/Retro-Claisen cascade was proposed. Bzhyperforin (4) showed significant cytotoxicity against MDA-MB-231 cells with an IC50 value of 6.88 ± 1.37 μM. more...
- Published
- 2020
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