New Eudesmane Sesquiterpenoids from Salvia plebeia R. Br.

Three new sesquiterpenoids, salplebeones A – C ( 1  –  3 ), were isolated from the ethanol‐soluble extract of the aerial part of Salvia plebeia R. Br . Their structures were established by detailed analysis of NMR and MS spectra. Salplebeone A was an eudesmane lactone, while salplebeones B and C were rare eudesmane sesquiterpenoids, containing 12,8‐lactam groups. Antiproliferative activities of salplebeones A – C to myeloid leukemia cell lines were evaluated.     

Chemical characterisation of the terpenoid constituents of the Algerian plant Launaea arborescens

Chemical investigation of endemic Algerian plant Launaea arborescens resulted in the isolation of a series of triterpenes and sesquiterpenes from both the aerial parts and roots. Five terpenoids have been chemically characterised by means of spectral methods mainly NMR techniques. In addition, the absolute stereochemistry at the chiral carbon in the side chain of 8-deoxy-15-(3′-hydroxy-2′-methyl-propanoyl)-lactucin-3′-sulfate (6) has been determined by comparison of the ¹H NMR spectra of Mosher derivatives of 6 with those of the corresponding MTPA esters of model compounds.     

ent-Eudesmane sesquiterpenoids, galloyl esters of the oak lactone precursor, and a 3-O-methylellagic acid glycoside from the wood of Platycarya strobilacea

ent-Eudesmane sesquiterpenoids, 8,11-dihydroxy-2,4-cycloeudesmane, 11-hydroxy-2,4-cycloeudesman-8-one and 2,4-cyclo-7(11)-eudesmen-8-one, were isolated from the wood of Platycarya strobilacea, which has been used as an aromatic tree since at least the 18th century. On charring the wood, 2,4-cyclo-7(11)-eudesmen-8-one was detected in the smoke. In the charred wood, the concentrations of ellagitannins, such as galloyl pedunculagin, dramatically decreased, whereas concentrations of pentagalloyl glucose, and other gallotannins were relatively stable. In addition, two other compounds, the 6′-O-m- and p-digalloyl oak lactone precursor and the 3-O-methylellagic acid 4′-O-(4″-O-galloyl)-xylopyranoside, were isolated from the charred wood along with m- and p-digallic acid.     

Eudesmane derivatives and other constituents from Saussurea parviflora

A survey of the whole plant of Saussurea parviflora afforded three compounds 11,12,13-trihydroxy-4(15),8-eudesmadiene-9-one, eudesman-8beta,12-olide-1-O-beta-D-glucoside and 1beta,3beta-dihydroxyursa-9(11),12-diene-3-octadecanoate, as well as 13 known compounds. Their structures were elucidated on the basis of spectral evidence, especially by using NMR spectroscopic techniques. In addition, encelin exhibited effective antitumor activity on L02, SMMC-7721 and HO-8910 cells.     

A novel eudesmane sesquiterpene glycoside from Ambrosia artemisiifolia L.

A new eudesmane sesquiterpene glycoside (1), five known eudesmane sesquiterpenoids (2–6), and seven known compounds (7–13), were obtained from Ambrosia artemisiifolia. Their structures were elucidated mainly by NMR and MS methods. Among them, compounds 1–4 and 6–9 were isolated from the A. artemisiifolia for the first time and the chemotaxonomic significance of these compounds was summarized.     

ent-Clerodane diterpenes and other constituents from the liverwort Adelanthus lindenbergianus (Lehm.) Mitt

Eleven ent-clerodanes, 13-hydroxy-cis-ent-cleroda-3,14-diene, 15-hydroxy-cis-ent-cleroda-3,13(E)-diene, 1beta,12:15,16-diepoxy-cis-ent-cleroda-13(16),14-dien-18alpha,6alpha-olide, 8beta,12:15, 16-diepoxy-cis-ent-cleroda-13(16),14-dien-18alpha,6alpha-olide, 1beta,16:15,16-diepoxy-cis-ent-cleroda-12,14-dien-18alpha,6alpha-olide, 7beta,12:8beta,12-diepoxy-15-hydroxy-cis-ent-cleroda-13-en-16,15:18alpha,6alpha-diolide, 7beta,12:8beta,12-diepoxy-16-hydroxy-cis-ent-cleroda-13-en-15,16:18alpha,6alpha-diolide, 1alpha-acetoxy-8beta,12-epoxy-15-hydroxy-cis-ent-cleroda-13-en-16,15:18alpha,6alpha-diolide, 1beta,12-epoxy-16-hydroxy-cis-ent-cleroda-13-en-15,16:18alpha,6alpha-diolide, 8beta,12-epoxy-15-hydroxy-trans-cleroda-13-en-16,15:18alpha,6alpha-diolide, 8beta,12-epoxy-16-hydroxy-trans-cleroda-13-en-15,16:18alpha,6alpha-diolide along with the known clerodane diterpenes anastreptin and orcadensin have been isolated from the liverwort Adelanthus lindenbergianus (Lehm.) Mitt. Furthermore, three eudesmane sesquiterpenes together with the known (-)-1beta,10-epoxyaristolan, 3,4-seco-4(23),20(29)-lupadien-3,28-dicarboxylic acid dimethyl ester and two acetophenone derivatives were identified by spectroscopic methods, essentially MS and NMR experiments.     

Two new eudesmane sesquiterpenoids from Daucus carota L.

Two new eudesmane sesquiterpenoids were isolated from the fruits of Daucus carota L. The structures were established based on the interpretation of high-resolution MS and 1D- and 2D-NMR data, the absolute configuration of compound 1 was determined by single-crystal X-ray diffraction. The new compounds were elucidated as (1βH, 3βH, 5βH, 7αH)-4α, 10α-dimethyl-7β-isopropyl-1α, 3α, 4β, 11-tetrahydroxy decahydronaphthalene (1) and (1βH, 3βH, 5βH, 7αH)-4α, 10α-dimethyl-7β-isopropyl-1α, 3α, 4β-trihydroxy decahydronaphthalene-11-O-β-d-glucopyranoside (2). The compound 1 showed significant antioxidant activity.     

Terpenoids from the seeds of Artemisia annua

Fourteen sesquiterpenes, three monoterpenes and one diterpene natural product have been isolated from the seeds of Artemisia annua. The possible biogenesis of some of these natural products are discussed by reference to recently reported experimental results for the autoxidation of dihydroartemisinic acid and other terpenoids from Artemisia annua.     

Three types of sesquiterpenes from rhizomes of Atractylodes lancea

Eight sesquiterpenes, including four guaiane-types containing an interesting epoxy unit (1-4), a rare tricyclic carbon skeleton-type (5) and three eudesmane-types (6-8), along with five known compounds, were isolated from rhizomes of Atractylodes lancea. The structures and relative configurations of 1-8 were determined by analysis of spectroscopic data, and the absolute configuration of 8 was assigned by application of the CD technique. Compounds 1, 2 and 4 were evaluated for their cytotoxic effects against P388 and A549 cells, but all were inactive. Possible biosynthetic pathways for sesquiterpenes (1-8) were discussed.     

Linderolides A-F, eudesmane-type sesquiterpene lactones and linderoline, a germacrane-type sesquiterpene from the roots of Lindera strychnifolia and their inhibitory activity on NO production in RAW 264.7 cells in vitro

From the roots of Lindera strychnifolia, seven sesquiterpenes, named linderolides A-F and linderoline, were isolated together with six known compounds. The structures of linderolides A-F were elucidated to be eudesmane-type sesquiterpenes and linderoline was found to be a derivative of a germacrane-type sesquiterpene. Their structures were elucidated by means of spectroscopic evidence and that of linderolide A was confirmed by X-ray analysis. The inhibitory activity toward NO production was assayed using RAW264.7 cells with evaluating the cell growth by MTT method, linderolides C, D and F being found to be moderately active.