Polycyclic Polyprenylated Acylphloroglucinols from Hypericum himalaicum

Abstract

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 and 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, and IL-6, downregulated the protein expression of COX-2 and iNOS, and 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.

Highlights

• Six new polycyclic polyprenylated acylphloroglucinols (PPAPs) with a vicinal diol moiety were isolated from the whole plant of Hypericum himalaicum.

• The absolute configurations of vicinal diol were determined by the Mo₂(OAc)₄-induced circular dichroism (ICD).

• Compound 1 may inhibit inflammation by blocking the NF-κB pathway and inhibiting NLRP3 inflammasome activation.

Keywords

Hypericum himalaicum - Hypericaceae - PPAPs - ICD - anti-inflammation

Publication History

Received: 24 June 2024

Accepted after revision: 27 April 2025

Accepted Manuscript online:
28 April 2025

Article published online:
20 May 2025

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