Polycyclic polyprenylated acylphloroglucinols from Hypericum himalaicum

Six previously undescribed polycyclic polyprenylated acylphloroglucinols (PPAPs) with a vicinal diol moiety (1–6), were isolated from the whole plant of Hypericum himalaicum. Their structures were established through a comprehensive analysis of HRMS, 1D and 2D NMR data, while the absolute configurations were determined using the Mo2(OAc)4–induced circular dichroism (ICD), ECD and NMR calculations. Compound 1 attenuated the secretion of NO, TNF-α, IL-6, and downregulated the protein expression of COX-2, iNOS as well as inhibited the release of ROS in LPS-induced RAW264.7 macrophages. Further investigation revealed that the anti-inflammatory effects may be attributed to the inhibition of the NF-κB and NLRP3 signaling pathways.