Sesquiterpene lactones from Smyrnium cordifolium

In addition to previously obtained furanosesquiterpenes, two new eudesmanolides and a new glechomanolide were isolated from the fruits of Smyrnium cordifolium, while the roots gave two new eudesmanolides. The new compounds from the fruits were 1β-acetoxy-eudesman-4(15), 7(11)-dien-8,12-olide, 1β-acetoxy-8β-hydroxy-eudesman-4(15),7(11)-dien-8,12-olide, 1β,10α;4α,5β-diepoxy-8-hydroxy-glechomanolide, those obtained from the roots were smyrnicordiolide and the corresponding 8β-hydroxy derivative belonging to a new type of oxepine derivative.     

Glechomanolides and eudesmanolides from Smyrnium perfoliatum

In addition to five known sesquiterpenoids, six new compounds were isolated from Smyrnium perfoliatum. The new compounds were 1β-acetoxy-eudesma-3,7(11),8-trien-8,12-olide, 1β-acetoxyeudesma-4(15),7(11),8-trien-8,12-olide, 1β-10α;4α,5β-diepoxy-8β-isobutoxy-glechomanolide, 1β, 10α;4α,5β-diepoxy-8α-isobutoxy-glechomanolide, 1β,4α-dihydroxy-2α,3α-epoxy-eudesma-7(11),8-dien-8,12-olide, 1β,4α-dihydroxy-2α,3α-epoxy-8β-methoxy-eudesma-7(11)-en-8α,12-olide.     

Diterpenoids of Halimium viscosum

From the neutral fraction of the hexane extract of Halimium viscosum the following components were isolated; 7-labdene-3β,l5-diol, 15-acetoxy-7-labden-3β-ol and a new diterpene-lactone with a rearranged ent-labdane skeleton, 13S-ent-9, 1-friedo-labd-1(10)-en-15-acetoxy-2R,18-olide. From the non-saponifiable part, beside 7-labdene-3β, 15-diol and 7, 13E-labdadiene-3β, 15-diol, the new diterpene 8(17)-labdene-3β, 7α, 15-triol was extracted. The structures were elucidated by spectroscopic methods, correlations or synthesis.     

Eudesmane sesquiterpenoid lactones and abietane diterpenoids from Ajuga forrestii Diels

Four eudesmane sesquiterpenoid lactones (1–4) and seven abietane diterpenoids (5–11) were isolated from the whole plants of Ajuga forrestii. Among them, 3α-acetoxy-1α,8β-dihydroxyeudesm-7(11)-en-8,12-olide (1), 3α-acetoxy-1α-hydroxyl-eudesm-8,7(11)-dien-8,12-olide (2), 1α-acetoxy-8α-oxyethyl-2-oxo-eudesman-3,7(11)-dien-8,12-olide (3) and 2α,3β,11,12-tetrahydroxy-7β,20-epoxy-8,11,13-abietatriene (11) are novel compounds. The structures of compounds 1–11 were determined by spectroscopic analysis. Compound 2 exhibited weak cytotoxicity on HepG2 and MCF-7 cell lines.     

Two new triterpenoids from Rhodomyrtus tomentosa

Repetition of an investigation of the petrol extracts of Rhodomyrtus tomentosa has led to the isolation of two new triterpenoids, R₄ from the leaves and R₅ from the stems besides R₁, R₂, R₃ and the other known compounds already reported. R₁ and R₄ were proved to be 21α$\text{H}$-hop-22(29)en-3β,30-diol and 3β-hydroxy-21α$\text{H}$-hop-22(29)-en-30-al respectively, and R₂, R₃ and R₅ are 3β-acetoxy-11α,12α-epoxyoleanan-28,13β-olide, 3β-acetoxy-12α-hydroxyoleanan-28, 13β-olide and 3β-acetoxy-12-oxo-oleanan-28,13β- olide respectively. The ethanol extract of the leaves contained betulinic, ursolic and aliphitolic acids and that of the stems betulonic, betulinic and oleanolic acids.     

Two new sesquiterpenes from Ligularia dictyoneura

The detailed investigation of the whole plant of Ligularia dictyoneura was performed during a search for unique chemical skeletons. One novel noreremophilane-type sesquiterpene, (4S, 5R, 8R, 10S)-1-nor-10-hydroxy-8-methoxyeremophil-7(11)-en-12,8-olide (1) and one new highly oxygenated eremophilane, 1β-angeloyloxy-6α, 10β-dihydroxyeremophil-7(11), 8-dien-12, 8-olide (2), were obtained. Their structures, including the absolute configuration, were elucidated by spectroscopic data and CD analysis.     

Sesquiterpene lactones of Podanthus mitiqui

Ovatifolin and two new sesquiterpene lactones, deacetylovatifolin and arturin (1β-hydroxy-8β-angeloyloxy-eudesmane-4(15),11(13)-diene-6α,12-olide, have been isolated from stems and leaves of Podanthus mitiqui. Two of these compounds showed cytotoxic activity.     

New sesquiterpene lactones from Inula oculus-christi L.

Investigation of the aerial parts of Inula oculus-christi L. led to the identification of four new sesquiterpene lactones: an eudesmanolide (4α,15α-epoxypulchellin E) and three guaianolides (2α-acetoxy-4α,9β-dihydroxy-1β-guaia-11(13),10(14)-dien-12,8α-olide, 9β,10β-epoxygaillardin, 9α,10α-epoxy-2-epi-gaillardin), in addition to the known gaillardin, pulchellin E, pulchellin C and 3-O-palmitates of 16β-hydroxylupeol, 16β-hydroxy-β-amyrin, and faradiol. The structures of all compounds have been elucidated on the basis of their spectral data.     

Sesquiterpene lactones from the fruits of Smyrnium connatum

A new sesquiterpene lactone, 1β,8-dihydroxyeremophila-3,7(11)dien-8,12-olide, was identified in the fruits of Smyrnium Connatum, along with five known lactones.     

Sesquiterpene lactones from Artemisia maritima

Two new sesquiterpene lactones have been isolated from Artemisia maritima and the structures have been assigned on the basis of their spectral properties as 1-oxo-6β,7α,11βH,14β-methylgermacra-4(5)-ene-12,6-olide and 1-oxo-6β,7α,11βH-germacra-4(5),10(14)-dien-12,6-olide.     

Antiproliferative and apoptotic sesquiterpene lactones from Carpesium faberi

Four new (1-4) and 13 known (5-17) sesquiterpene lactones along with two known diterpenes (18, 19) were isolated from the whole plant of Carpesium faberi. The new structures were elucidated by means of spectroscopic techniques and some chemical transformations to be pseudoguaian-1α(H)-8α,12-olide-4β-O-β-d-glucopyranoside (1), 4β,10α-dihydroxy-5α(H)-1,11(13)-guaidien-8α,12-olide (2), 4β,10β-dihydroxy-5α(H)-1, 11(13)-guaidien-8β,12-olide (3), and (4S)-acetyloxyl-11(13)-carabren-8β,12-olide (4). All isolates were tested against MCF-7 human breast cancer cells using the MTT assay. Among them, the sesquiterpene lactones (except tomentosin 17) possessing an α-methylene-γ-lactone moiety were found to have in vitro antiproliferative activities, with IC₅₀ values of 3.0-38.8 μg/mL. The effects of four selected sesquiterpene lactones (guaianolide 2, carabranolide 4, pseudoguaianolide 9, eudesmanolide 13) on the cell cycle were examined using flow cytometry (FCM).     

Isoscutellarein and hypolaetin 8-glucuronides from the liverwort Marchantia berteroana

The major flavonoid of Marchantia berteroana is hypolaetin 8-O-β-d-glucuronide. This is accompanied by apigenin and luteolin, isoscutellarein (8-hydroxyapigenin) 8-O-β-d-glucuronide, the 7-O-β-d-glucuronide and -galacturonide of apigenin and luteolin, luteolin 3′-O-β-d-glucuronide and -galacturonide, luteolin 7,3′-di-O-β-d-glucuronide and -galacturonide, luteolin 3′,4′-di-O-β-d-glucuronide and -galacturonide, luteolin 7,4′-di-O-β-d-glucuronide, and hypolaetin 8,4′-di-O-β-d-glucuronide. The isoscutellarein and hypolaetin glucuronides, and the galacturonide flavones are all new natural products.     

Two sesquiterpene lactones from Trichogonia gardneri

The structures and stereochemistries of two sesquiterpene lactones from Trichogonia gardneri were established as (6R,7S,8S,9S,IOR)-4E-9,10-dihydroxy-8-tigloxygermacr-4-en-6,12-olide) and (5R*,6R*,7S*,8S*,9R*)-14-acetoxy-3-chloro-9-hydroxy-2-oxo-8-tigloxyguia-1(10),3-dien-6,12-of olide by a combination of NMR spectrometry and X-ray diffraction. The results show that the structures of several sesquiterpene lactones which were isolated previously from related species require revision.     

The structure of leocardin,two epimers of a diterpenoid from Leonurus cardiaca

From the aerial part of Leonurus cardiaca a new labdane diterpenoid, leocardin, has been isolated and its structure was established by spectroscopic and chemical means. It has been shown to be 8β-acetoxy-9α,13α,15,16-bisepoxy-15-hydroxy-7-oxo-labdan-6β,19-olide present as a C-15 epimeric mixture.     

Flavonoids of the liverwort Marchantia polymorpha

The major flavonoids of Marchantia polymorpha var. polymorpha and aquatica are the 7-O-β-d-glucuronides of apigenin and luteolin, luteolin 3′-O-β-d-glucuronide, luteolin 7,3′-di-O-β-d-glucuronide, and the 7,4′-di-O-β-d-glucuronides of apigenin and luteolin. These are accompanied by minor amounts of apigenin, luteolin, luteolin 3′,4′-di-O-β-d-glucuronide and luteolin 7,3′,4′-tri-O-β-d-glucuronide. All the luteolin di- and triglucuronides except the 3′,4′-di- substituted compound are new natural products.     

Sesquiterpenes and diterpenes from Ambrosia arborescens

Six compounds, eudesm-11(13)-en-4β,9β-diol, 15R,16-dihydroxy-3-oxoisopimar-9(11)-ene, 15S,16-dihydroxy-3-oxoisopimar-9(11)-ene, 1α-hydroxy-7-oxo-iso-anhydrooplopanone, 10α-hydroxy-11,13-dihydro-5-epi-psilostachyin, and 4β-hydroxypseudoguaian-12,6-olide 4-O-β-d-glucopyranoside, together with 12 known sesquiterpenes, were isolated from the leaves of Ambrosia arborescens. Structures were elucidated by 1D and 2D NMR spectroscopy including 1D-TOCSY, DQF-COSY, 2D-ROESY, HSQC, and HMBC experiments, as well as by ESI mass spectrometry. The absolute configuration of the 15,16-diol moiety in 15R,16-dihydroxy-3-oxoisopimar-9(11)-ene and 15S,16-dihydroxy-3-oxoisopimar-9(11)-ene was determined using Snatzke’s method. All compounds were evaluated for antiproliferative activity.     

Chemotaxonomic significance of lindenane sesquiterpenoid dimers and eudesmane sesquiterpenoids from Chloranthus henryi Hemsl. var. hupehensis (Pamp.) K. F. Wu

Seventeen known compounds were isolated from the 95% alcohol extract of the aerial parts of Chloranthus henryi Hemsl. var. hupehensis (Pamp.) K. F. Wu, including five lindenane sesquiterpenoid dimers (1–5) and twelve eudesmane sesquiterpenoids (6–17). In the present research, compounds 3 sarcaglabrin C, 6 neolitacumone C, 7 ent-Atractylenolide III and 8 dehydrocarissone were reported from the Chloranthus genus for the first time, and compounds 1 spicachlorantin B, 2 chloramultilide C, 4 shizukaol B, 5 japonicone C, 9 6α-hydroxyeudesma-4(15),7(11),8(9)-triene-12,8-olide, 10 ent-(3R)-3-hydroxyatractylenolide III, 11 8βH-hydroxyeudesma-4(14),7(11)-dien-12,8-olide, 12 lasianthuslactone A, 13 (5S,6R,8S,10R)-6-hydroxyeudesma-4(15),7(11)-diene-12,8-olide, 14 4β-hydroxy5α,8β(H)-eudesm-7(11)-en-8,12-olide, 15 4β,8β-dihydroxy-5α(H)-eudesm-7(11)-en-8,12-olide, 16 curcolonol and 17 1β, 8β-dihydroxyeudesm - 3,7(11)-dien-8α,12-olide were firstly isolated from the plant. Their structures were elucidated on the basis of extensive spectroscopic and chemical analyses. Moreover, the chemotaxonomic significance of the isolated compounds is discussed.     

Neo-clerodane diterpenoids from Teucrium pyrenaicum

From the aerial part of Teucrium pyrenaicum three new neo-clerodane diterpenoids have been isolated. Their structures, 3β-acetoxy-4α,18:12S,2OS: 15,16:19, 2OS-tetraepoxy-neo-cleroda-13(16),14-dien-6-one (teupyrenone), 3β,6α,19-triacetoxy- 4α,18:15,16-diepoxy-neo-cleroda-13(16),14-dien-20,12S-olide (teupyreinin), and 3β, 6α,19,2OS-tetra-acetoxy-4α,18:12S,2OS: 15,16-triepoxy-neo-cleroda-13(16), 14-diene (teupyreinidin), were established mainly by spectroscopic means.     

The germacranolides of Viguiera buddleiaeformis structures of budlein-A and -B

The structure of budlein-A, the main sesquiterpene lactone of Viguiera buddleiaeformis was established as the 8 angeloyl ester of 1 keto, 8-β, 14-dihydroxy germacra-2,4,11 (13)-trien-3, (10 β) oxido-6 α, 12-olide. Its structure and stereochemistry was determined by chemical and spectroscopic means. Budlein-B, found in the same plant as a minor constituent, is 8 α, 15-dihydroxygermacra-1 (10), 4, 11 (13)-trien-6 α, 12-olide.     

Flavonoids of Helichrysum chasmolycicum and its antioxidant and antimicrobial activities

From the aerial parts of Helichrysum chasmolycicum P.H Davis, which is an endemic species in Turkey, the flavonoids apigenin, luteolin, kaempferol, 3,5-dihydroxy-6,7,8-trimethoxyflavone, 3,5-dihydroxy-6,7,8,4′-tetramethoxyflavone, apigenin 7-O-glucoside, apigenin 4′-O-glucoside, luteolin 4′-O-glucoside, luteolin 4′,7-O-diglucoside, kaempferol 3-O-glucoside, kaempferol 7-O-glucoside and quercetin 3-O-glucoside were isolated. The methanol extract of the aerial parts of H. chasmolycicum showed antioxidant activity by DPPH method (IC₅₀ 0.92 mg/mL). Antimicrobial activity test was performed on the B, D, E extracts and also 3,5-dihydroxy-6,7,8-trimethoxyflavone and kaempferol 3-O-glucoside which were the major flavonoid compounds obtained from aerial parts of H. chasmolycicum by microbroth dilutions technique. The E (ethanol-ethyl acetate) extract showed moderate antimicrobial activity against Pseudomonas aeruginosa, B (petroleum ether-60% ethanol-chloroform) extract and 3,5-dihydroxy-6,7,8-trimethoxyflavone showed moderate antifungal activity against Candida albicans.