Further terpenoids from the Chloranthaceae plant Chloranthus multistachys and their anti-neuroinflammatory activities.

Three labdane-type [multisins A–C (1 – 3)], two guaiane-type [multisins D (4) and E (5)], and one eudesmane-type [multisin F (6)] previously undescribed terpenoids, together with 14 mono- (7 – 20) and seven dimeric- (21 – 27) known terpenoids, were isolated from the 90% MeOH extract of the whole plant of Chloranthus multistachys. Their structures and absolute configurations were determined by extensive spectroscopic methods and electronic circular dichroism (ECD) calculations. Compounds 4 and 5 are rare trinor-sesquiterpenes with a de-isopropyl guaiane skeleton, whereas compound 6 is a rearranged dinor-eudesmene featuring an uncommon octahydro-1 H -indene ring system. Among the isolates, the dimeric lindenane sesquiterpenoid shizukaol C (25) exhibited the most potent (IC 50 = 8.04 μM) anti-neuroinflammatory activity by inhibiting the nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated murine BV-2 microglial cells. [Display omitted] • A phytochemical reinvestigation on the herb Chloranthus multistachys was reported. • Six previously undescribed di−/sesqui-terpenoids (multisins A–F) were identified. • Multisins D/E are rare trinor-sesquiterpenes with a de-isopropyl guaiane skeleton. • Multisin F is an unusual dinor-eudesmane featuring a rearranged ring system. • Shizukaol C exhibited relatively the most potent anti-neuroinflammatory activity. [ABSTRACT FROM AUTHOR]