Polyprenylated acylphloroglucinol meroterpenoids with PTP1B inhibition from Hypericum forrestii.

Three new polyprenylated acylphloroglucinol meroterpenoids, hyperiforins A–C (1 – 3), were isolated from Hypericum forrestii (Chittenden) N. Robson, together with twelve known analogues (4 – 15). Their structures were established by extensive physical and spectroscopic data analysis. Compounds 1 , 2 , 5 , 7 , and 13 – 15 showed potent inhibitory effects on protein tyrosine phosphatase 1B with IC 50 values from 6.63 ± 2.40 to 14.21 ± 3.51 μ M. [Display omitted] • Three new polyprenylated acylphloroglucinol meroterpenoids, hyperiforins A–C (1 – 3), together with twelve known congeners (4 – 15) were isolated from Hypericum forrestii (Chittenden) N. Robson. • The putative biosynthetic pathways for the tertiary hydroperoxyl group in 2, 3, 5, 9, 11, and 12 have been proposed for the first time. [ABSTRACT FROM AUTHOR]