Chlorfortunones A and B, Two Sesquiterpenoid Dimers, Possessing Dispiro[4,2,5,2]pentadecane-6,10,14-tren Moiety from Chloranthus fortunei

Abstract

Chlorfortunones A ( 1 ) and B ( 2 ), two novel sesquiterpenoid dimers, were isolated from the roots of Chloranthus fortunei . Their structures were elucidated by spectroscopic analysis and X-ray diffraction analysis. Compounds 1 and 2 represent a new type of sesquiterpenoid dimer possessing an unprecedented 3/5/6/6/6/5 hexacyclic system with a unique dispiro[4,2,5,2]pentadecane-6,10,14-trien moiety. A plausible biosynthetic pathway of 1 and 2 was proposed. Compound 1 showed transforming growth factor (TGF)-β inhibitory activity in MDA-MB-231 cells.

Chemistry and bioactivity of lindenane sesquiterpenoids and their oligomers

“…72 Besides the abundant LSs with conjugated units, non-LSs with different skeletons can serve as diene or dienophile units to form hetero-[4 + 2] LS oligomers. 36,37,65,71 The second category of LS oligomers occurs through [2 + 2] cycloaddition between two D 8 ′ (9 ′ ) and [6 + 6] cycloaddition between the highly conjugated D 15(4),5(6),7 (11) , which is uncommon in nature. 70,[73][74][75][76] There will still be highly conjugated fragments in the oligomers of LSs aer the occurrence of [6 + 6] cycloaddition, also suggesting that the subsequent intramolecular rearrangement and cyclization products will be very rich and unusual (Fig.…”

“…28 Subsequent oxidative rearrangement further enhances the structural diversity, such as sarglaromatic D, 68 fortunoid A, 69 and chlorahupetone G. 70 Meanwhile, Δ 15(4),5(6) can also react with Δ 11′(13′) and Δ 15′(4′) or other double bonds of the non-LS unit. 71 Also, Δ 7(11),8(O) can exist as a diene moiety and undergo oxygenate [4 + 2] cycloaddition. 72 Besides the abundant LSs with conjugated units, non-LSs with different skeletons can serve as diene or dienophile units to form hetero-[4 + 2] LS oligomers.…”

Boswellianols A–I, Structurally Diverse Diterpenoids from the Oleo-Gum Resin of Boswellia carterii and Their TGF-β Inhibition Activity

“…In this study, the more polar methanolic fraction was subjected to chromatographic separation, which resulted in the isolation and identification of one new diterpenoid with a novel prenylmaaliane-type skeleton (1), three new prenylaromadendrane-type diterpenoids (2)(3)(4), four new cembrane-type diterpenoids (5)(6)(7)(8)(9), and three known compounds (10)(11)(12). As one part of our ongoing screening of lead compounds for inhibiting TGF-β from natural products [24][25][26], the TGF-β inhibitory activities of isolated compounds were evaluated in LX-2 human hepatic stellate cells, and the results showed that compounds 1 and 5 exhibited TGF-β-inhibitory activities.…”

Hot off the press

“…The structure of the sesquiterpenoid dimer chlorfortunone A 19 , from Chloranthus fortunei , was established by X-ray analysis. 17 Chlorfortunone A 19 possesses a novel dispiro hexacyclic ring system that the authors suggest is formed by a Diels–Alder cycloaddition between lindenane and acorane sesquiterpenoid precursors. The structure of the chamigrane sesquiterpenoid dimer antroxazole A 20 , from Antrodiella albocinnamomea , was also established by X-ray analysis.…”