Two New Sesquiterpenes from Euonymus nanoides

Two new dihydroagarofuran sesquiterpenes with a novel substitution pattern:1α-(α-methyl)-butanoyl-2α,15-diacetoxy-4β-hydroxy-9β-(β-)furancarboxy-β-dihydroagarofuran (1) and 1α,2α-di-(α-methyl)-butanoyl-4β-hydroxy-9β-(β-)furancarboxy-15-acetoxy-β-dihydro-agaro-furan (2) were isolated from Euonymus nanoides. Their structures were elucidated by means of ^1H and ^13C NMR spectroscopic studies, including 2D NMR technique.     

Two New Sesquiterpenes from Euonymus phellomana Loes

Two new 0-dihydroagarofuran sesquiterpene polyo! esters have been isolated fromEuonymlls phellomanQ 'Loes. growing in Wen county, Gansu Province of China.Compound 1, white needle crystals, mp: 154-156oC, analyzed for C,,H,=O,, byFABMS (m/zf 623, M 1) and ElMS showed peaks due to the loss of acetic acid, 0furoic acid and a-methylbutanoic acid. IR showed ester carbonyl at 1745 cm-' andhydroxyl at 3420cm-'. The IHNMR and "CNMR spectrum revealed the presence ofthree acetoxy, one (6-)fu…     

微波辅助萃取鬼箭羽叶中芦丁和槲皮素

建立了鬼箭羽中主要有效成分芦丁和槲皮素的MAE-HPLC定量分析方法, 该方法具有测定准确、操作简便和分析速度快等优点. 此外, 利用扫描电镜观察了鬼箭羽叶经微波辅助萃取后植物结构的变化, 初步证明了微波辅助萃取鬼箭羽叶的萃取机理符合细胞破壁学说.     

Two New Sesquiterpenes from Myrrh

Two new sesquiterpenes, named 9‐methoxymyrrhone ( 1 ) and rel‐(1S,2S,3R,4S)‐1,2‐epoxy‐3‐methoxyfuranogermacr‐10(15)‐en‐6‐one ( 2 ), together with nine known compounds ( 3 – 11 ), were isolated from the resin of Commiphora opobalsamum. The structures were established by HR‐ESI‐MS, 1D‐, and 2D‐NMR spectroscopic analyses.     

Two New Pseudoguaianolides from the Flowers of Parthenium hysterophorus

Chemical investigation on two samples of the flowers of Parthenium hysterophorus afforded two new pseudoguaianolides (one from each sample) together with several known constituents. The structures of the new compounds were established by extensive spectroscopic (1D‐ and 2D‐NMR) studies. The X‐ray crystallographic analysis of one of these compounds was also accomplished.     

Two New Sesquiterpenes from Euonymus nanoides

Two new sesquiterpenes,1β-(β-)furancarboxy-4α,13-diacetoxy-9β-cinna-moyloxy-β-dihydroagarofuran(1) and 1β，6α-di-(α-methyl)-butanoyl-4α-hydroxy-9β-enzoyloxy-13-acctoxy-β-dihydroagarofuran (2), were isolated from the seed oil of Euonymous nanoides,Their strucures were elucidated on the basis of spectral data.     

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.     

New Sesquiterpene Formamides from the Marine Sponge Axinyssa sp.

Chemical investigation of an extract of the marine sponge Axinyssa sp., collected from the South China Sea, led to the isolation and identification of two new sesquiterpene formamides, (4R*,5R*,10R*)‐4‐formamidoeudesm‐7‐ene ( 1 ) and (4R*,5R*,7S*,10R*)‐4‐formamidoeudesman‐11‐ol ( 2 ), together with the known 4α‐formamidogorgon‐11‐ene ( 3 ). Their structures were elucidated by spectroscopic methods, including 1D‐ and 2D‐NMR spectroscopy, high‐resolution ESI‐TOF mass spectrometry, as well as X‐ray single‐crystal diffraction experiments. Possible biosynthetic pathways for 1 – 3 were also proposed. The human nasopharyngeal cancer cell line CNE‐2, human cervical cancer cell line HeLa, and human normal liver cell line L02 were used to examine the cytotoxic activities of 1 – 3 in vitro. As the results, 1 showed significant cytotoxic activity against CNE‐2, HeLa, and L02 cell lines with the IC₅₀ values of 13.8, 7.5, and 38.0 μg/ml, resp.     

Two New Meroterpenes from the Mangrove Endophytic Fungus Aspergillus sp. 085241B

Two new meroterpenes, ‘acetoxydehydroaustin B’ ( 1 ) and ‘1,2‐dihydro‐acetoxydehydroaustin B’ ( 2 ) were isolated in the form of a mixed crystal from the mangrove endophytic fungus Aspergillus sp. 085241B. Their structures and absolute configurations were determined by extensive analysis of their spectra and X‐ray diffraction data. In a preliminary bioassay, the mixed crystal did not exhibit activities against cancer cell lines of MDA‐MB‐435, SKBR3, HepG2, HEP3B, PC‐3, and A549, as well as against α‐glucosidase and tyrosinase.     

Two New Sesquiterpenes from Ligularia Duciformis

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Two New Guaiane Sesquiterpenes from the Fruits of Daucus carota

Two new sesquiterpenes, 11‐(acetyloxy)torilolone ( 1 ) and 1β‐hydroxytorilolone ( 2 ) were obtained from the fruits of Daucus carota. Their structures were elucidated on the basis of various spectroscopic analyses and chemical evidence.     

Two New Sesquiterpenes from the Fungus Stereum sp.

Two new sesquiterpenes, stereumin F ( 1 ) and stereumin G ( 2 ), together with two known compounds (3β,5α,22E,24R)‐5,8‐epidioxyergosta‐6,22‐dien‐3‐ol ( 3 ) and 4‐(2‐hydroxyethyl)phenol ( 4 ), were isolated from the AcOEt extract of the culture broth and the MeOH extract of the mycelium of the fungal strain Stereum sp. CCTCC AF 207024. Their structures were established on the basis of spectral analyses.     

Two New Daphniphyllum Alkaloids from Daphniphyllum calycinum

Two new daphniphyllum alkaloids named 2‐hydroxyyunnandaphnine D ( 1 ) and methyl 7‐hydroxyhomodaphniphyllate ( 2 ), together with eight known alkaloids, daphnioldhanin D, calyciphylline F, calyciphylline B, deoxycalyciphylline B, daphnicyclidin H, macropodumine C, 9,10‐epoxycalycine A, and yunnandaphnine A, were isolated from the stems and leaves of Daphniphyllum calycinum. Their structures and relative configurations were established on the basis of spectral evidence (including 2D‐NMR) and subsequently confirmed by a single‐crystal X‐ray crystallographic diffraction analysis.     

New Sesquiterpenes from Chloranthus japonicus

Chemical investigation of the roots of Chloranthus japonicus Sieb . has resulted in the isolation and characterization of four new eudesmane‐type sesquiterpenes including two new sesquiterpene cinnamates, along with one new and two known sesquiterpene dimers. Their structures were established by spectroscopic means and by comparison with the respective literature values.     

New Selenosemicarbazides Derived from Imidazole‐Based Carbohydrazides

Imidazole‐based carbohydrazides, i.e., 3‐oxidoimidazole‐4‐carbohydrazides 1 and 2‐[(imidazol‐2‐yl)sulfanyl]acetohydrazides 6 , react with aryl isoselenocyanates 4 in MeOH at room temperature to give the corresponding selenosemicarbazides 5 and 7 , respectively, in good yields. On heating 7b in DMF in the presence of air to 100°, 1,3,4‐oxadiazole 8a was formed via cyclization and formal elimination of H₂Se. Product 8a was also obtained after heating of a mixture of 4a and 6b under the same conditions. On the other hand, on heating of a solution of 7c in MeOH at reflux, a cyclization occurred to give the corresponding 1,2,4‐triazole‐3‐selone 9b . Again, the same product was formed when a mixture of 4b and 6b was heated in MeOH. Surprisingly, analogous cyclizations of selenosemicarbazides of type 5 under the same conditions failed, and only decomposition was observed. The structures of 7a, 7d , and 9b have been established by X‐ray crystallography.     

New Labdane‐Type Diterpenoids from Leonurus heterophyllus

Chemical investigation of the aerial part of Leonurus heterophyllus led to the isolation and characterization of the seven labdane‐type diterpenoids 1 – 7 , including six new ones, 1 – 6 . Compounds 4 and 5 were isolated as a C(15) epimer pair. The determination of the structures and relative configurations of the new compounds were mainly based on 1D‐ and 2D‐NMR spectroscopic methods, and comparison of their NMR data with related compounds. The structure of compound 7 was confirmed by X‐ray crystallographic analysis.     

Two Unusual Methylidenecyclopropane Glucosides from Metaxya rostrata C.Presl

Two new natural compounds, (1R,2E)‐2‐(6‐hydroxyhexylidene)cyclopropyl‐β‐D ‐glucopyranoside ( 1 ) and (6E)‐6‐[(2R)‐2‐(β‐D ‐glucopyranosyloxy)cyclopropylidene]hexanoic acid ( 2 ), glucosides of a very rare methylidenecyclopropane alcohol, as well as two known glycosides of phenolic acids, namely 4‐O‐β‐D ‐glucopyranosylcaffeic acid ( 3 ) and (E)‐4‐O‐β‐D ‐glucopyranosylcoumaric acid ( 4 ), and methyl α‐fructofuranoside ( 5 ) were isolated for the first time from the rhizomes of the tree fern Metaxya rostrata C.Presl . The structures were elucidated on the basis of detailed spectroscopic data analysis, and the structure of 1 was additionally confirmed by X‐ray crystal‐structure analysis.     

Three new sesquiterpenes from Euonymus schensianus Maxim

Three new sesquiterpenes,namely schensianol A(1),schensianolside A(2) and schensianolside B(3) were isolated from the stems and leaves of Euonymus schensianus Maxim.Their structures were established by chemical methods and spectroscopic techniques including 2D NMR.     

New Dihydroagarofuranoid Sesquiterpenes from Celastrus paniculatus

The six new dihydro‐β‐agarofuranoid sesquiterpenes 1 – 6 and three known compounds were isolated from the whole plant of Celastrus paniculatus. The structures including relative configurations were elucidated by means of spectroscopic analyses. Compounds 1 – 6 were evaluated for cytotoxicity against a panel of three human‐tumor cell lines.