Three Novel Eremophilanolides from Ligularia virgaurea spp. oligocephala

From the alcoholic extract of the whole plant of Ligularia virgaurea spp. oligocephala, three novel eremophilane sesquiterpene lactones, 6α, 10α-dihydroxy- 1-oxoeremophila-7(11), 8(9)-dien-8, 12-olide, 613, 10α-dihydroxy-1-oxoeremophila-7 (ll), 8 (9)-dien-8, 12-olide and 10α-hydroxy-1-oxoeremophila-7(l 1), 8(9)-dien-8, 12-olide were isolated. Their structures were elucidated by various spectroscopic methods including intensive 2D NMR techniques (COSY,HMQC, HMBC and ^1H-^1H NOESY) and HR-MS.     

Two New Eremophilenolides from Ligularia sagitta

Chemical investigation of L.sagitta afforded two new eremophilenolides, which were identified as 6β-angeloyloxy-10β-hydroxy-8 β-methoxy-eremophil-7(11)-en-12, 8α-olide (1) and 6β, 8β-dimethoxy-10β-hydroxy-eremophil-7(11)-en-12, 8α-olide (2). Their structures were estab- lished by spectroscopic methods including 2D NMR experiments.     

A New Triterpene and New Sesquiterpenes from the Roots of Ligularia sagitta

One new triterpene and seven new eremophilane‐type sesquiterpenes were isolated from the roots of Ligularia sagitta, among them 1a , an O‐acetylated oleanane type triterpene, 2a and 3a , two 11‐nor eremophilane‐type sesquiterpenes, 4a, 5 , and 6 , three standard eremophilane‐type sesquiterpenes, and 7 and 8 , two tri‐nor eremophilane‐type sesquiterpenes. Their structures were established by extensive spectral analyses (1D, 2D‐NMR, IR, and MS). Compound 1a showed moderate cytotoxicity against two tumor cell lines.     

Four new eremophilendiolides from Ligularia atroviolacea

From Ligularia atroviolacea, four new eremophilendiolides, 81$-hydroxy-eremophil-3,7 （11）-dien-12,8α（14,6α）-diolide （1）, 8β-methoxy-eremophil-3,7（11）-dien-12,8α（14,6α）-diolide （2）, 8α-hydroxy-eremophil-3,7（11）-dien-12,8lβ（14,6α）-diolide （3） and eremophil-3,7（11）,8-trien-12,8 （14,6α）-diolide （4）, as well as a known diolide （5） were isolated. Their structures were elucidated on the basis of 1D and 2D NMR as well as ESI-MS spectral data.     

Four new bisabolane-type sesquiterpenes from Ligularia lankongensis

The chemical constituents of the roots of two Ligularia lankongensis samples collected in Yunnan and Sichuan Provinces, China, were investigated, together with the DNA sequence of the atpB-rbcL and ITS regions. Four new highly oxygenated bisabolane-type sesquiterpenes (1 - 4) were obtained. Intraspecific diversity in the DNA sequence was found to be limited.     

Novel Sesquiterpenes from Ligularia virgaurea spp. oligocephala

Two novel sesquiterpene dimers, ligularin A ( 1 ) and ligulolide D ( 2 ), and one new sesquiterpenoid, 1β,10α‐dihydroxy‐6β‐[(2‐methylpropyl)oxy]furanoeremophil‐9‐one ( 3 ), as well as two known sesquiterpenoids, 6β‐[(2‐methylpropyl)oxy]‐furanoeremophil‐1(10)‐en‐9‐one ( 4 ) and 1‐hydroxy‐3,7‐dimethyl‐2‐(pent‐3‐enyl)benzofuran ( 5 ), were isolated from the petroleum‐ether fraction from an alcoholic extract of the whole plant of Ligularia virgaurea spp. oligocephala. Their structures were elucidated by 1D and 2D‐NMR spectroscopy together with HR‐ESI‐MS analysis, and comparison of the spectroscopic data with those reported for structurally related compounds. In addition, the cytotoxicities against human gastric cancer SGC‐7910 cell were measured in vitro, the results demonstrated that these sesquiterpenes have no cytotoxicity against the selected tumor cell (all IC₅₀ values >200 μM ).     

Two Cytotoxic Eremophilanolides from Senecio tsoongianus

Two new eremophilanolides, tsoongianolide E and F, were isolated from Senecio tsoongianus. Their structures were elucidated on the basis of NMR and MS spectra. Both of these two compounds showed in vitro cytotoxicity to cultured KB and A-549 cancer cell lines.     

A Novel Dimeric Eremophilane from Ligularia virgaurea spp. oligocephala

A novel dimeric eremophilane, ligulolide B, was isolated from the alcoholic extract of the whole plant of Ligularia virgaurea spp. oligocephala. The structure was elucidated by various spectroscopic methods including intensive 2D NMR techniques （^1H-^1H COSY, gHMQC, gHMBC and ^1H-^1H NOESY） and HR-ESI-MS.     

Sesquiterpenoids from Ligularia dentata

Five new compounds were isolated from the roots of Ligularia dentata, including four bisabolane‐type sesquiterpenoids, 1 – 4 , as well a new eudesmane, 5 . The previously isolated 3α,6α,9‐tris(angeloyloxy)‐2α,4β‐dihydroxy‐7,11‐epoxybisabol‐10(15)‐en‐5‐one ( 6 ), when left as an oil in a refrigerator over nine months, gave rise to a mixture of two positional isomers, 7 and 8 . Their formation is rationalized by means of epoxide ring opening and shift of an angeloyl (Ang) group. The structures of compounds 1 – 5, 7 , and 8 were established by in‐depth spectroscopic (UV, CD, IR, 1D‐ and 2D‐NMR) as well as mass‐spectrometric methods.     

Sesquiterpenes from Ligularia Hodgsonii

A new nor‐sesquiterpenoid eremophilane derivative and a new eudesmane derivative were isolated from the whole plants of Ligularia hodgsonii. Their structures were elucidated by spectroscopic methods and 2D NMR techniques.     

Sesquiterpenes from Ligularia Fischeri

Phytochemical investigation of the whole plant of Ligularia fischeri afforded two new sesquiterpenes 11‐hydroxy‐eremophil 1(10)‐en‐2,9‐dione (1) ; and 1β,11‐dihydroxy‐eremophil‐9‐ene (2) ; four known compounds (‐)‐4β,7α‐aromadendranediol (3) ; 1β,6α‐dihydroxyeudesm‐4(15)‐ene (4) ; Teucdiol A (5) ; Teucdiol B (6) . The new compound structures were elucidated by spectroscopic methods including 2D‐NMR techniques.     

New Sesquiterpenoids from Ligularia duciformis

From the whole plants of Ligularia duciformis, four new sesquiterpenoids, 3β‐acetoxy‐6β‐methoxyeremophila‐7(11),9(10)‐dien‐12,8β‐olide ( 1 ), 3β‐acetoxy‐8α‐hydroxy‐6β‐methoxyeremophila‐7(11),9(10)‐dien‐12,8β‐olide ( 2 ), 3β‐acetoxy‐10β‐hydroxy‐6β,8β‐dimethoxyeremophil‐7(11)‐en‐12,8α‐olide ( 3 ), and 3β‐acetoxy‐6β,8β,10β‐trihydroxyeremophil‐7(11)‐en‐12,8α‐olide ( 4 ) were isolated. Their structures were established by high‐field NMR techniques (¹H,¹H‐COSY, ¹³C‐APT, HMQC, HMBC, and NOESY) and HR‐ESI‐MS analysis, together with comparison of the spectroscopic data with those of structurally related compounds. In addition, the cytotoxicity of the new compounds against human hepatic cancer cells Bel‐7402, human pneumonic cancer cells A‐549, and human colonic cancer cells HCT‐8 were evaluated, the new compounds showed no cytotoxicity against the three tumor cells (all IC₅₀ values >200 μM ).     

Benzofuran Derivatives from Ligularia Stenocephala

Four new benzofuran derivatives were isolated from the roots of Ligularia stenocephala; they were named as ligustenin A ( 1 ), B ( 2 ), C ( 3 ) and D ( 4 ), and the structures were established by spectroscopic methods including 2D NMR techniques. Ligustenin A (1) was found to exhibit potent anti‐tumor activity against HL‐60 (human leukemia cells), Bel‐7402 (human hepatoma cells) and HO‐8910 (human ovarian neoplasm cells) with IC₅₀ values of 18.6, 27.6 and 57.5 μM, respectively.     

Eremophilane Sesquiterpenoids from Ligularia fischeri

A novel eremophilane dimer, named as fischelactone, and a new sesquiterpene lactam, eremophila‐1(10),7(11),8‐triene‐12,8‐lactam, along with ten known compounds, were isolated from the roots of Ligularia fischeri. Their structures were established by means of spectroscopic analyses (EI‐MS, HR‐ESI‐MS, IR, and 1D‐ and 2D‐NMR data) and X‐ray diffraction study.     

Bisabolane Sesquiterpenes from Ligularia thyrsoidea

Phytochemistry investigation of the whole plants of Ligularia thyrsoidea, has led to the isolation of five new bisabolane sesquiterpenes along with three known compounds. The structures of these new compounds were elucidated by spectroscopic methods and 2D NMR techniques.     

Phaeophytin analogues from Ligularia knorringiana

A new phaeophytin, ligulariaphytin A, together with five known phaeophytins, were isolated from the aerial parts of Ligularia knorringiana. The structure of ligulariaphytin A was elucidated as 131-hydroxy-131,132-peroxyphaeophorbide A ethyl ester, and the five known compounds were identified as 132-hydroxyphaeophorbide A ethyl ester, 173-ethoxyphaeophorbide A, phaeophytin B, phaeophytin A, and phaeophorbide B ethyl ester, respectively, based on spectroscopic analysis and by comparison of their spectral data with those reported previously in the literature. All compounds were evaluated for their in vitro cytotoxic activities against cultured Hela cell, and were found to show only very weak cytotoxicity.     

Four Novel Hydropyranoindeno-Derivatives from Marine Fungus Aspergillus versicolor

In the previous report on bioactive secondary metabolites from the sponge-associated fungus Aspergillus versicolor (Vuill) Tirab, the bioassay guiding fractionation led to isolation of six new compounds with unusual skeleton based on chromone ring system from the inculated fungus which was isolated from fresh samples of marine sponge Xestospongia exigua, collected along coast line of Bali, Indonesia in 19971. In the continuation of our chemical investigation on the marine fungus, four compou…     

Four Novel Diterpenoids from Crinipellis sp. 113

Four novel diterpenoids, namely (4β)‐4,4‐O‐dihydrocrinipellin A ( 1 ), (4β,8α)‐4,4‐O,8,8‐O‐tetrahydrocrinipellin B ( 2 ), crinipellin C ( 3 ), and crinipellin D ( 4 ), along with three known ones, (3β,4β)‐3,3‐C,4,4‐O‐tetrahydrocrinipellin A ( 5 ), (4β)‐4,4‐O‐dihydrocrinipellin B ( 6 ), and phlebiakauranol alcohol, were isolated from the fungal strain Crinipellis sp. 113. Their structures were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR experiments, and by HR‐Q‐TOF mass spectrometry. Antitumor and antibacterial assays with the novel compounds 1 – 4 were carried out, showing moderate activities against HeLa cells and no effects on the growth of tested bacteria or yeast.     

Two New Sesquiterpenes from Ligularia lankongensis

In continuation of a systematic investigation into the chemotaxonomic and bioactive components of pyrrolizidine alkaloids and sesquiterpenoids of Ligularia plants, two new, highly oxygenated, rare bisabolene sesquiterpenes, compounds 1 and 2 , were isolated from the roots of Ligularia lankongensis. Their structures and relative configurations were elucidated by means of 1D‐ and 2D‐NMR as well as MS analyses.