RÉSUMÉ
Three new cleistanthane diterpenoids, phyllanglins A-C (1-3), a new natural product, 4-acetyl-bergenin (4), and three known compounds (5-7) were isolated from the roots of Phyllanthus glaucus. Their structures were elucidated by extensive spectroscopic data analyses and single-crystal X-ray diffraction. Phyllanglins A-C were unusual cleistanthane diterpenoids with phenylacetylene moieties, and a plausible biogenetic pathway was proposed to discuss the origins of them. All of the isolates were evaluated for their anti-inflammatory activities.
Sujet(s)
Acétylène/analogues et dérivés , Diterpènes/isolement et purification , Phyllanthus/composition chimique , Racines de plante/composition chimique , Acétylène/isolement et purification , Animaux , Anti-inflammatoires/isolement et purification , Anti-inflammatoires/pharmacologie , Cristallographie aux rayons X , Diterpènes/pharmacologie , Souris , Structure moléculaire , Cellules RAW 264.7RÉSUMÉ
A novel covalent-triazine framework (CTF-PO71) is designed and prepared from an organic pigment molecule for high-performance gas separation. The functional sites with different electrostatic potentials on the pore surface of CTF-PO71 demonstrate a strong interaction between C2 H2 and CTF-PO71 to achieve preferential adsorption of C2 H2 over C2 H4 , thus enabling effective capture of a trace amount of C2 H2 from the gas mixture. This is the first organic porous polymer that is capable of separating C2 H2 and C2 H4 . The commercial availability and the low cost of the pigment as well as the high stability of the resultant framework endow CTF-PO71 with a significant potential for practical applications.
Sujet(s)
Acétylène/isolement et purification , Éthylènes/isolement et purification , Triazines/composition chimique , Acétylène/composition chimique , Adsorption , Éthylènes/composition chimique , Structure moléculaire , Porosité , Propriétés de surface , Triazines/synthèse chimiqueRÉSUMÉ
Hydrogen-bonded complexes of acetylene (Ac) with the polymers polystyrene (PS), poly(4-vinylpyridine) (P4VP), and poly(2-vinylpyridine) (P2VP) have been characterized for the first time at 16 K in a "polymer soft-landing isolation" experiment which is being pioneered in our research laboratory. In particular, changes in vibrational modes of Ac provide ample evidence for hydrogen-bonded complexes between Ac and the phenyl groups of PS or the pyridyl groups of P4VP and P2VP. With PS, the proton on the top Ac molecule of the classic T-shaped Ac dimer interacts with the π cloud of the benzene (Bz) ring to form a C-H---π interaction, while the π cloud of the lower Ac forms a second C-H---π interaction with a proton on the Bz ring. An analogous (ring)1-(Ac)2 double interaction occurs between an Ac dimer and the pyridine (Pyr) rings on both P2VP and P4VP, yielding a C-H---N and C-H---π interaction. With P4VP and P2VP a second bridged (ring)2-(Ac)2 product is formed, with the Ac dimer forming nearly collinear C-H---N hydrogen bonds to adjacent Pyr rings. On P2VP this bridged product is the only one after extensive annealing. These complexes in which Ac acts as both proton donor and acceptor have not previously been observed in conventional matrix isolation experiments. This study is the second from our laboratory employing this method, which represents a slight modification of the traditional matrix isolation technique.
Sujet(s)
Acétylène/composition chimique , Acétylène/isolement et purification , Polymères/composition chimique , Polystyrènes/composition chimique , Polyvinyles/composition chimique , Liaison hydrogène , Modèles moléculaires , Théorie quantiqueRÉSUMÉ
A pytochemical study on the constituents of the roots of Symphyotrichum subulatum led to the isolation of three new compounds including two diacetylenes, asterynes A (1) and B (2), and (E)-4-(3-acetoxyprop-1-enyl)-2-methoxyphenyl (S)-2-methylbutanoate (3) along with twelve known compounds. Their structures were elucidated with spectroscopic analyses. Compound 3 showed anti-inflammatory activity on LPS-induced NO production with an EC50 value of 15.0 µM.
Sujet(s)
Acétylène/composition chimique , Acétylène/isolement et purification , Asteraceae/composition chimique , Phénol/composition chimique , Acétylène/analogues et dérivés , Acétylène/pharmacologie , Animaux , Anti-inflammatoires non stéroïdiens/composition chimique , Anti-inflammatoires non stéroïdiens/isolement et purification , Anti-inflammatoires non stéroïdiens/pharmacologie , Butyrates/composition chimique , Butyrates/isolement et purification , Évaluation préclinique de médicament , Lipopolysaccharides/effets indésirables , Macrophages/composition chimique , Macrophages/effets des médicaments et des substances chimiques , Spectroscopie par résonance magnétique , Souris , Structure moléculaire , Monoxyde d'azote/composition chimique , Phénols/composition chimique , Phénols/isolement et purification , Extraits de plantes/composition chimique , Racines de plante/composition chimiqueRÉSUMÉ
A soluble and stable one-handed helical poly(substituted phenylacetylene) without the coexistence of any other chiral moieties was successfully synthesized by asymmetric-induced polymerization of a chiral monomer followed by two-step polymer reactions in membrane state: (1) removing the chiral groups (desubstitution); and (2) introduction of achiral long alkyl groups at the same position as the desubstitution to enhance the solubility of the resulting one-handed helical polymer (resubstitution). The starting chiral monomer should have four characteristic substituents: (i) a chiral group bonded to an easily hydrolyzed spacer group; (ii) two hydroxyl groups; (iii) a long rigid hydrophobic spacer between the chiral group and the polymerizing group; (iv) a long achiral group near the chiral group. As spacer group a carbonate ester was selected. The two hydroxyl groups formed intramolecular hydrogen bonds stabilizing a one-handed helical structure in solution before and after the two-step polymer reactions in membrane state. The rigid long hydrophobic spacer, a phenylethynylphenyl group, enhanced the solubility of the starting polymer, and realized effective chiral induction from the chiral side groups to the main chain in the asymmetric-induced polymerization. The long alkyl group near the chiral group avoided shrinkage of the membrane and kept the reactivity of resubstitution in membrane state after removing the chiral groups. The g value (g = ([θ]/3,300)/ε) for the CD signal assigned to the main chain in the obtained final polymer was almost the same as that of the starting polymer in spite of the absence of any other chiral moieties. Moreover, since the one-handed helical structure was maintained by the intramolecular hydrogen bonds in a solution, direct observation of the one-handed helicity of the final homopolymer has been realized in CD for the solution for the first time.
Sujet(s)
Acétylène/analogues et dérivés , Membrane artificielle , Polymérisation , Acétylène/synthèse chimique , Acétylène/composition chimique , Acétylène/isolement et purification , Dichroïsme circulaire , Liaison hydrogène , Conformation moléculaire , Spectrophotométrie IR , Spectrophotométrie UV , StéréoisomérieRÉSUMÉ
A new acetylenic alkaloid was isolated from the sponge Leucetta sp. The structure was established by analyzing spectroscopic data. The alkaloid showed cytotoxicity IC50 2.5 µg/mL against NBT-T2 cells.
Sujet(s)
Acétylène/pharmacologie , Alcaloïdes/pharmacologie , Porifera/composition chimique , Acétylène/administration et posologie , Acétylène/isolement et purification , Alcaloïdes/administration et posologie , Alcaloïdes/isolement et purification , Animaux , Antinéoplasiques/administration et posologie , Antinéoplasiques/isolement et purification , Antinéoplasiques/pharmacologie , Lignée cellulaire tumorale , Concentration inhibitrice 50 , Rats , Analyse spectraleRÉSUMÉ
AIM OF THE STUDY: Our previous research has showed that rhizome of Atractylodes japonica Koidz (Compositae) exhibits an increase in the spontaneous contractility of distal colon in rats. The aims of this study are to identify the phytochemical(s), which stimulate(s) the colonic contractility, contained in Atractylodes japonica and to evaluate the pharmacological mechanism responsible for the colonic muscle contraction. MATERIALS AND METHODS: Based on the stimulatory activity-guided fractionation on the isometric contraction of rat distal colonic strips, atractylodiol (ATD) and diacetyl-atractylodiol (DATD) were isolated from the CHCl(3) fractions of Atractylodes japonica. RESULTS: ATD and DATD dose-dependently increased both tension and amplitude of distal colon longitudinal muscle (DCLM), but they stimulated only amplitude in the distal colon circular muscle. The ED(50) values of ATD and DATD to stimulate the amplitude of DCLM were revealed as 9.1×10(-9)M and 1.8×10(-8)M, respectively. l-NAME (0.1mM) significantly increased the ADT (1µM)-induced contraction of DCLM, whereas SNAP (0.1mM) markedly reduced the stimulatory effects of ATD on DCLM contractility. The combined effects of SNAP and atropine (0.5µM) on the ATD-induced contraction of DCLM were similar to the inhibitory effects of SNAP alone. Suramin (0.1mM) significantly enhanced the increase of ATD-induced DCLM contraction, whereas ADPßS (0.1mM) markedly abolished the stimulatory effects of ATD on the spontaneous contractility of DCLM. CONCLUSIONS: The present results demonstrate that acetylene compounds, ATD and DATD, are the effective phytochemical of Atractylodes japonica to stimulate the motility of distal colon in rats, and ATD possibly enhances the spontaneous contractility of distal colon through inhibiting the mechanism of nitrergic-purinergic relaxation.
Sujet(s)
Acétylène/pharmacologie , Atractylodes/composition chimique , Côlon/effets des médicaments et des substances chimiques , Neurones nitrergiques/métabolisme , Récepteurs purinergiques/métabolisme , Acétylène/isolement et purification , Animaux , Côlon/métabolisme , Côlon/physiologie , Techniques in vitro , Mâle , Contraction musculaire/effets des médicaments et des substances chimiques , Rats , Rat Sprague-DawleyRÉSUMÉ
A screening of 30 crude extracts of marine sponges against human promyelocytic leukemia cells (HL-60) yielded an EtOAc extract of the sponge Callyspongia sp. (Callyspongiidae) with significant activity. Further bioassay-guided fractionation of the EtOAc extract led to the isolation of three polyacetylene metabolites: a new polyacetylene diol, callyspongidiol (1), along with two known compounds, siphonodiol (2) and 14,15-dihydrosiphonodiol (3). Their structures were determined by a combination of spectroscopic analyses. Compounds 1-3 exhibited antiproliferative activity against HL-60 with IC(50) values of 6.5, 2.8, and 6.5 microg/ml, respectively. These metabolites induce apoptosis in HL-60 cells. Dendritic cells (DC) differentiated with 1-3 enhance the differentiation of naïve T cells towards the Th1 type.
Sujet(s)
Callyspongia/composition chimique , Leucémie aiguë promyélocytaire/traitement médicamenteux , Polyynes/pharmacologie , Acétylène/administration et posologie , Acétylène/analogues et dérivés , Acétylène/isolement et purification , Acétylène/pharmacologie , Animaux , Antinéoplasiques/administration et posologie , Antinéoplasiques/isolement et purification , Antinéoplasiques/pharmacologie , Apoptose/effets des médicaments et des substances chimiques , Différenciation cellulaire/effets des médicaments et des substances chimiques , Polarité de la cellule , Prolifération cellulaire/effets des médicaments et des substances chimiques , Cellules dendritiques/effets des médicaments et des substances chimiques , Cellules dendritiques/métabolisme , Tests de criblage d'agents antitumoraux/méthodes , Cellules HL-60 , Humains , Concentration inhibitrice 50 , Polymères/administration et posologie , Polymères/isolement et purification , Polymères/pharmacologie , Polyynes/administration et posologie , Polyynes/isolement et purification , Lymphocytes auxiliaires Th1/métabolismeRÉSUMÉ
Two new acetylenic fatty acids (1, 2), a new triglyceride (3), along with eleven known compounds including 3-oxo-11alpha,12alpha-epoxyurs-13beta,28-olide (4) previously reported as a synthetic compound, have been isolated from the leaves of Hymenodictyon excelsum. The structural identification was established from spectroscopic data.
Sujet(s)
Acétylène/isolement et purification , Acides gras/isolement et purification , Feuilles de plante/composition chimique , Rubiaceae/composition chimique , Triglycéride/isolement et purification , Triterpènes/isolement et purification , Acétylène/composition chimique , Acides gras/composition chimique , Spectroscopie par résonance magnétique , Extraits de plantes/composition chimique , Normes de référence , Triglycéride/composition chimique , Triterpènes/composition chimiqueRÉSUMÉ
Siphonodiol is a polyacetylene diol isolated from marine sponges Callyspongia sp. We demonstrate that the effect of Siphonodiol on the phenotypic and functional maturation of human monocyte derived DC in vitro. Human monocytes were exposed to Siphonodiol alone, or in combination with LPS and thereafter co-cultured with naïve T cells. The expression levels of CD1a, CD80, CD83, CD86 and HLA-DR on LPS-primed DC were partially enhanced by Siphonodiol. Siphonodiol augmented the T cell stimulatory capacity in an allo MLR to LPS-primed DC. Siphonodiol dose-dependently enhanced the production of IL-12p70 by LPS-primed DC and this cytokine production was inhibited by anti-TLR4 mAb. IFN-gamma secretion from naive T cells co-cultured with DC differentiated with LPS was augmented by Siphonodiol. These results suggest that the enhancement of Th1 cells polarization to LPS-primed DC induced by Siphonodiol depends on TLR4 and via the activation of IL-12p70.
Sujet(s)
Acétylène/analogues et dérivés , Différenciation cellulaire/effets des médicaments et des substances chimiques , Cellules dendritiques/immunologie , Monocytes/immunologie , Polymères/pharmacologie , Acétylène/composition chimique , Acétylène/isolement et purification , Acétylène/pharmacologie , Animaux , Anticorps monoclonaux/immunologie , Anticorps monoclonaux/pharmacologie , Antigènes CD/immunologie , Callyspongia/composition chimique , Différenciation cellulaire/immunologie , Cellules cultivées , Techniques de coculture , Cellules dendritiques/cytologie , Humains , Interleukine-12/immunologie , Lipopolysaccharides/pharmacologie , Monocytes/cytologie , Polymères/composition chimique , Polymères/isolement et purification , Lymphocytes auxiliaires Th1/cytologie , Lymphocytes auxiliaires Th1/immunologie , Récepteur de type Toll-4/antagonistes et inhibiteurs , Récepteur de type Toll-4/immunologieRÉSUMÉ
1-Phenylhepta-1,3,5-triyne (1), 5-phenyl-2-(1'-propynyl)-thiophene (2), and 2-(3'-acetoxy-1'-propynyl)-5-phenylthiophene (3) were isolated from Coreopsis lanceolata L., and their structures identified by spectroscopic methods. Compounds 1 and 2 showed effective nematicidal activities against Bursaphelenchus xylophilus and Caenorhabditis elegans, but had hardly any effect against Pratylenchus penetrans. Compound 3 did not show any effective nematicidal activity.
Sujet(s)
Antihelminthiques antinématodes/toxicité , Coreopsis/composition chimique , Nematoda/effets des médicaments et des substances chimiques , Acétylène/composition chimique , Acétylène/isolement et purification , Acétylène/toxicité , Animaux , Antihelminthiques antinématodes/composition chimique , Antihelminthiques antinématodes/isolement et purification , Caenorhabditis elegans/effets des médicaments et des substances chimiques , Echinochloa/croissance et développement , Éthanol , Fleurs/composition chimique , Spectroscopie par résonance magnétique , Pinus , Racines de plante/parasitologie , Plant/croissance et développementRÉSUMÉ
Two solvent-modified MEKC methods were developed for the quantitative analysis of heterocyclic amines synthesised using intramolecular ring closure via catalysed hydroamination. The first method was capable of resolving six of the amines (precursors and products) with a sample-to-sample injection time of 2 min employing a 20 mM borate buffer, pH 9.2 with 20 mM SDS and 5% v/v n-butanol (n-BuOH). A second low-pH method using 20 mM phosphate buffer, 100 mm SDS, 5% v/v n-BuOH and 20% v/v iso-propanol (i-PrOH) was able to resolve an additional pair of compounds with a sample-to-sample time of 3.5 min. Application of the first method to the analysis of a sample containing catalyst as well as amines placed directly in a 96-well plate showed excellent performance, with migration time and peak height and area reproducibility being less than 0.9 and 9.6%, respectively. The quantity of conversion by catalyst was calculated to be 68 +/- 7%, which was in excellent agreement with the 67 +/- 5% obtained by more conventional (1)H NMR experiments, with the added advantage that this method is also cheaper, quicker and more amendable to high-throughput screening of combinatorial libraries.
Sujet(s)
Chromatographie électrocinétique micellaire capillaire/méthodes , Techniques de chimie combinatoire/méthodes , Électrophorèse capillaire/méthodes , Acétylène/analogues et dérivés , Acétylène/composition chimique , Acétylène/isolement et purification , Dérivés de l'aniline/composition chimique , Dérivés de l'aniline/isolement et purification , Catalyse , Reproductibilité des résultatsRÉSUMÉ
Two new acetylenic glucosides, 4',6'-acetonide-8Z-decaene-4,6-diyne-1-O-beta-D-glucopyranoside named carthamoside A(1) (1) and 4,6-decadiyne-1-O-beta-D-glucopyranoside named carthamoside A(2) (2), along with one known acetylenic glucoside, 8Z-decaene-4,6-diyne-1-O-beta-D-glucopyranoside (3), have been isolated from the air-dried flower of Carthamus tinctorius, these structures have been identified on the basis of spectroscopic methods.
Sujet(s)
Acétylène/analogues et dérivés , Acétylène/composition chimique , Carthamus tinctorius/composition chimique , Glucosides/composition chimique , Acétylène/isolement et purification , Fleurs/composition chimique , Glucosides/isolement et purification , Spectroscopie par résonance magnétique/méthodes , Spectroscopie par résonance magnétique/normes , Conformation moléculaire , Normes de référence , Sensibilité et spécificité , StéréoisomérieRÉSUMÉ
The structure-activity relationship of 12 isolated acetylenes from galls of Hedera rhombea (Araliaceae) induced by Asphondylia sp. (Cecidomyiidae) and their derivatives has been studied for the inhibition of the shoot and root growth of rice, perennial ryegrass, cockscomb, lettuce, and cress. Almost all acetylenes generally showed growth inhibitory activity. The diacetylenes exhibited higher activity than the monoacetylenes, suggesting that a conjugated diyne segment is essential for the activity. On the other hand, the acetylenes with a nonoxidated methylene group at C-8 showed stronger activity comparing with those possessing hydroxy and acetoxy groups at C-8. Furthermore, it has been demonstrated that the acetylenes bearing a terminal olefinic group at C-16, C-17 enhanced the activity. It is thus clarified that important sites for the activity of the acetylenes from galls of H. rhombea are a conjugated diyne and a terminal olefinic group connecting to the aliphatic chain and that less oxidated compounds show more activity.
Sujet(s)
Acétylène/composition chimique , Acétylène/pharmacologie , Hedera/composition chimique , Facteur de croissance végétal/pharmacologie , Acétylène/isolement et purification , Spectroscopie par résonance magnétique , Structure moléculaire , Pouvoir rotatoire , Racines de plante , Pousses de plante , Relation structure-activitéRÉSUMÉ
Bioassay-guided fractionation of n-hexane extracts of Echinacea pallida (Asteraceae) roots led to the isolation and structure elucidation of two polyacetylenes (1, 3) and three polyenes (2, 4, 5). Two are known hydroxylated compounds, namely 8-hydroxy-pentadeca-(9E)-ene-11,13-diyn-2-one (1) and 8-hydroxy-pentadeca-(9E,13Z)-dien-11-yn-2-one (2). Two dicarbonylic constituents, namely pentadeca-(9E)-ene-11,13-diyne-2,8-dione (3) and pentadeca-(9E,13Z)-dien-11-yne-2,8-dione (4), were isolated and characterized for the first time. Furthermore, the structure elucidation of pentadeca-(8Z,13Z)-dien-11-yn-2-one (5) is described. The structure of the compounds isolated was determined on the basis of UV, IR, NMR (including 1D and 2D NMR experiments, such as 1H-1H gCOSY, gHSQC-DEPT, gHMBC, gNOESY) and MS spectroscopic data. The cytotoxic activity of the isolated constituents against MIA PaCa-2 human pancreatic adenocarcinoma cells was evaluated in the concentration range 1-100 microg/ml. Results show that the hydroxylated compounds (1, 2) have low cytotoxicity, while the more hydrophobic polyacetylenes (3) and polyenes (4, 5) displayed moderate activity.
Sujet(s)
Acétylène/analogues et dérivés , Echinacea/composition chimique , Polyènes/composition chimique , Polyènes/toxicité , Polymères/composition chimique , Polymères/toxicité , Acétylène/composition chimique , Acétylène/isolement et purification , Acétylène/toxicité , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Humains , Spectroscopie par résonance magnétique , Structure moléculaire , Oxydoréduction , Polyènes/isolement et purification , Polymères/isolement et purification , Polyynes , Relation structure-activitéRÉSUMÉ
Many bioactive compounds with known effects on human physiology and disease have been identified through studies of plants used in traditional medicine. Some of these substances occur also in common food plants, and hence could play a significant role in relation to human health. Food plants of the Apiaceae plant family such as carrots, celery and parsley, contain a group of bioactive aliphatic C17-polyacetylenes. These polyacetylenes have shown to be highly toxic towards fungi, bacteria, and mammalian cells, and to display neurotoxic, anti-inflammatory and anti-platelet-aggregatory effects and to be responsible for allergic skin reactions. The effect of these polyacetylenes towards human cancer cells, their human bioavailability and their ability to reduce tumour formation in a mammalian in vivo model indicates that they may also provide benefits for health. The present state of knowledge on the occurrence of polyacetylenes in Apiaceae food plants, their biochemistry and bioactivity is presented in this review as well as relatively new methods for the isolation and quantification of these compounds from plants, plant products and biological fluids.
Sujet(s)
Acétylène/analogues et dérivés , Apiaceae/composition chimique , Plantes comestibles/composition chimique , Polymères/analyse , Acétylène/analyse , Acétylène/isolement et purification , Acétylène/pharmacologie , Chromatographie en phase liquide à haute performance , Chromatographie gazeuse-spectrométrie de masse , Polymères/isolement et purification , Polymères/pharmacologie , PolyynesRÉSUMÉ
Seven new long-chain acetylenic alcohols, strongylodiols D-J, were isolated from an Okinawan marine sponge of the genus Petrosia (Strongylophora). The structures of these compounds were elucidated on the basis of the results of spectroscopic analysis and chemical reaction. Analysis of the MNA esters of the acetylenic alcohols disclosed that these compounds were each an enantiomeric mixture in a different ratio.
Sujet(s)
Acétylène/analogues et dérivés , Acétylène/isolement et purification , Alcools/isolement et purification , Petrosia/composition chimique , Acétylène/composition chimique , Alcools/composition chimique , Animaux , Japon , Structure moléculaire , Résonance magnétique nucléaire biomoléculaire , StéréoisomérieRÉSUMÉ
Acyl-CoA: cholesterol acyltransferase (ACAT), which plays a role in the absorption, storage, and production of cholesterol, has been explored as a potential target for pharmacological intervention of hyperlipidemia and atherosclerotic disease. In our search for ACAT inhibitors from natural sources, the petroleum ether extract of Panax ginseng showed moderate inhibition of ACAT enzyme from rat liver microsomes. Bioactivity-guided fractionations led to the isolation of one new polyacetylenic compound, (9R,10S)-epoxy-16-heptadecene-4, 6-diyne-3-one (1), in addition to the previously reported polyacetylenic compounds 2 and 3. Their chemical structures were elucidated on the basis of spectroscopic evidence (UV, IR, NMR, and MS). The compounds 1, 2, and 3 showed significant ACAT inhibition with IC(50) values of 35, 47, and 21 microM, respectively.
Sujet(s)
Acétylène/analogues et dérivés , Acétylène/analyse , Acétylène/isolement et purification , Antienzymes/isolement et purification , Composés époxy/isolement et purification , Panax/composition chimique , Racines de plante/composition chimique , Polymères/analyse , Sterol O-acyltransferase/antagonistes et inhibiteurs , Acétylène/composition chimique , Acétylène/pharmacologie , Alcynes , Animaux , Diynes , Antienzymes/composition chimique , Antienzymes/pharmacologie , Composés époxy/composition chimique , Composés époxy/pharmacologie , Microsomes du foie/enzymologie , Structure moléculaire , Polymères/composition chimique , Polyynes , RatsRÉSUMÉ
A new acetylenic ketone isolated from the bark of Litsea rotundifolia var. oblongifolia has been characterized as 13-tetradecyn-2-one on the basis of detailed spectroscopic analysis and comparison with related model compounds. Four known related lipids have also been isolated from this plant.
Sujet(s)
Acétylène/analogues et dérivés , Acétylène/isolement et purification , Cétones/isolement et purification , Litsea/composition chimique , Acétylène/composition chimique , Alcynes , Cétones/composition chimique , Spectroscopie par résonance magnétiqueRÉSUMÉ
The isolation and structure elucidation of 1 from the Basidomycete fungus Baeospora myosura is described. This new ene-triyne antibiotic was most potent against Gram-positive bacteria, while it was less active against Gram-negative bacteria and a yeast. MICs against several strains of Staphylococcus aureus were as low as 0.001 microg/mL. Analogues of 1 that did not contain the ene-triyne moiety were inactive against all microorganisms tested. The isolation of this new natural product was complicated by the highly reactive nature of the conjugated terminal polyacetylene.