A novel ent-pimarane-type diterpenoid from Sigesbeckia glabrescens with anti-inflammatory activity

Abstract

A novel ent-pimarane-type diterpenoid, sigesbeckia J (1), along with two known diterpenoids, siegesbeckia acid (2) and ent-18-acetoxy-16R,17-dihydroxykauran-19-oic acid (3), were isolated from the aerial parts of Sigesbeckia glabrescens Makino. Their chemical structures were elucidated based on extensive spectroscopic interpretation. The absolute configuration of ent-pimarane-type diterpenoid (1) was determined by comparing experimental and calculated ECD spectra. Compared with the positive control minocycline (IC₅₀ 32.84 μM), compound 1 exhibited moderate cell growth anti-inflammatory activities in vitro by testing their inhibition of LPS-induced NO production in BV2 microglial cells, with IC₅₀ value of 58.74 μM.

Graphical Abstract

Keywords:

• Sigesbeckia glabrescens
• Compositae
• ent-pimarane-type
• diterpenoids
• anti-inflammatory

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was financially supported by the National Natural Science Foundation of China (No. 81903789) and the China Postdoctoral Science Foundation (2020M670675, 2020M680988).