RESUMEN
Methanolic extracts of soldiers of Nasutitermes guayanae and N. surinamensis have been shown to contain complex mixtures of diterpenes and monoterpenes. Eighteen diterpenes have been isolated and identified; twelve of them are previously known nasute termite diterpenes, while six are new trinervitene diterpenes. 2alpha,9beta-Dihydroxy-3beta,8beta-oxido-1(15)-trinervitene has been isolated from N. guayanae, while 3alpha,14alpha-diacetoxy-2beta-hydroxy-1(15),8(19),9-trinervitatriene, 14alpha-acetoxy-2beta,3alpha-dihydroxy-1(15),8(19),9-trinervitatriene, 2beta,3alpha-diacetoxy-11beta,14alpha-dihydroxy-1(15),8(19)-trinervitadiene, 9alpha,14alpha-diacetoxy-2beta,3alpha-dihydroxy-1(15),8(19)-trinervitadiene, and 2beta,9alpha,14alpha-triacetoxy-3alpha-hydroxy-1(15),8(19)-trinervitadiene have been isolated from N. surinamensis. Their structures were determined on the basis of their spectroscopic properties.
Asunto(s)
Diterpenos/aislamiento & purificación , Isópteros/química , Animales , Diterpenos/química , Diterpenos/farmacología , Guyana Francesa , Estructura Molecular , Resonancia Magnética Nuclear BiomolecularRESUMEN
The Indonesian marine sponge Callyspongia pseudoreticulata was found to contain (3S,18S,4E,16E)-eicosa-1,19-diyne-3,18-diol-4,16-diene (1), the structure of which was determined by detailed spectroscopic analysis. Its absolute configuration was established using the modified Mosher's method after esterification of the secondary alcohols with Mosher's reagent.
Asunto(s)
Acetileno/aislamiento & purificación , Polímeros/aislamiento & purificación , Poríferos/química , Acetileno/análogos & derivados , Acetileno/química , Alquinos , Animales , Diinos , Esterificación , Indicadores y Reactivos , Indonesia , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Polímeros/química , EstereoisomerismoRESUMEN
A new pentacyclic triterpene, 11alpha-acetoxy-20,24-epoxy-25-hydroxy-dammar-3-one (1), has been isolated from the African tree Combretum nigricans, together with the known corresponding diol, 20,24-epoxy-11alpha, 25-dihydroxy-dammar-3-one (2). They are responsible, at least in part, for the cytotoxic activity of the methanolic extract of the plant.
Asunto(s)
Antineoplásicos/farmacología , Combretum , Fitoterapia , Extractos Vegetales/farmacología , Triterpenos/farmacología , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Humanos , Concentración 50 Inhibidora , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Hojas de la Planta , Triterpenos/administración & dosificación , Triterpenos/química , Triterpenos/uso terapéutico , Células Tumorales Cultivadas/efectos de los fármacos , DamaranosRESUMEN
A method has been developed to assign the absolute configuration and enantiomeric excess of anabasine based on small amounts of material (in the microgram range), by derivatization with (+)-menthylchloroformate followed by capillary GC analysis of the resulting carbamate(s). This method was applied to three samples of anabasine isolated from Messor and Aphaenogaster ants. In Messor sanctus, only (2'S)-anabasine was present, whereas in Aphaenogaster subterranea and A. miamiana (2'S)-anabasine was determined to have an ee of 78 and 24%, respectively.
Asunto(s)
Anabasina/química , Hormigas/química , Insecticidas/química , Plantas , Anabasina/análisis , Animales , Cromatografía de Gases , Insecticidas/análisisRESUMEN
Secretions of the pronotal and elytral glands of adults of the chrysomelid beetle Platyphora opima from Panama have been shown to contain two oleanane triterpene saponins: the known 3-O-beta-D-glucopyranosyl-(1-->3)-beta-D-glucuronopyranosyl-oleano lic acid-28-O-beta-D-glucopyranoside and compound 1, whose structure was established as 3-O-beta-D-glucopyranosyl-(1-->3)-beta-D-glucuronopyranosyl-29- hydrox yoleanolic acid-28-O-beta-D-glucopyranoside by a combination of 1D and 2D NMR methods (COSY, HMQC, HMBC, and TOCSY) and FABMS. The secretions also contained N,N,N-trimethylcadaverine and its 1, 2-dehydro derivative 3, as well as the nicotinamide derivative 4. Secretions of Desmogramma subtropica, also from Panama, contained as sole triterpene derivative 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-24- hydrox yoleanolic acid (2), together with glutamic acid, glutamine, pyroglutamic acid, and arginine. A mixture of phosphatidylcholines was also present in the secretions of both species.
Asunto(s)
Aminoácidos/aislamiento & purificación , Escarabajos/química , Fosfatidilcolinas/aislamiento & purificación , Compuestos de Amonio Cuaternario/aislamiento & purificación , Saponinas/aislamiento & purificación , Triterpenos/aislamiento & purificación , Aminoácidos/química , Animales , Secuencia de Carbohidratos , Fosfatidilcolinas/química , Compuestos de Amonio Cuaternario/química , Saponinas/química , Análisis Espectral , Triterpenos/químicaRESUMEN
The Caribbean marine sponge Haliclona vansoesti was found to contain a high amount (5% dry wt) of a new analogue of 4-sphingenine, (2R,3R, 7Z)-2-aminotetradec-7-ene-1,3-diol (1). Its structure was determined by detailed spectroscopic analysis. The relative configuration was deduced from the NMR data of the corresponding acetonide 5, while the absolute configuration was secured via protection of the primary alcohol and amino groups, and esterification of the secondary alcohol with Mosher's reagent.
Asunto(s)
Poríferos/química , Esfingosina/análogos & derivados , Animales , Estructura Molecular , Análisis Espectral , Esfingosina/química , Esfingosina/aislamiento & purificaciónRESUMEN
The secretion of the defensive glands of adults of the chrysomelid beetle Platyphora ligata from Panama has been shown to contain, besides chlorogenic acid (1) and a mixture of phosphatidylcholines, two new oleanane triterpene saponins, named ligatosides A and B. Their structures were established as 3-O-beta-D-glucuronopyranosyl-16alpha,23-dihydroxyoleanol ic acid-28-O-2-(3,4-dimethoxybenzoyl)-beta-D-glucopyranoside (2) and 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-16a lpha, 23-dihydroxyoleanolic acid-28-O-2-(3, 4-dimethoxybenzoyl)-beta-D-glucopyranoside (3), respectively, by a combination of extensive 1D and 2D NMR methods (COSY, HMQC, HMBC, and TOCSY) and FABMS. This is the first report of triterpene saponins in the defensive secretion of an insect.
Asunto(s)
Escarabajos/química , Saponinas/aislamiento & purificación , Triterpenos/aislamiento & purificación , Animales , Ácido Clorogénico/análisis , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Espectroscopía de Resonancia Magnética , Panamá , Fosfatidilcolinas/análisis , Saponinas/análisis , Espectrometría de Masa Bombardeada por Átomos Veloces , Espectrofotometría Ultravioleta , Triterpenos/análisisRESUMEN
Two sponges of the genus Hyrtios have been found to contain new sesquiterpene/quinones identified by detailed spectroscopic analysis. Four new compounds with a 4,9-friedodrim-3-ene skeleton [hyrtiophenol (2), 5-epihyrtiophenol (3), 18-hydroxy-5-epihyrtiophenol (4), and 18-hydroxyhyrtiophenol (5)] were isolated from Hyrtios sp. (Seychelles Islands) along with isospongiaquinone (1). Moreover, the new compound 21-hydroxy-19-methoxyarenarone (8), which bears the 4, 9-friedodrim-4(15)-ene skeleton, was isolated from Hyrtios tubulatus (Curaçao) along with arenarol (6) and 5-epiilimaquinone (7). Assignment of the (13)C NMR signals of four types of 4, 9-friedodrimene skeletons found in sponges is presented.
Asunto(s)
Poríferos/química , Quinonas/aislamiento & purificación , Sesquiterpenos/aislamiento & purificación , Acetilación , Animales , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Espectrofotometría Infrarroja , Espectrofotometría UltravioletaRESUMEN
Two marine sponges of the genus Monanchora (Poecilosclerida, Crambeidae) have been found to contain new polycyclic guanidine alkaloids bearing the (5,6,8b)-triazaperhydroacenaphthylene skeleton. Their structures have been determined by detailed spectroscopic analysis. Dehydrobatzelladine C (1) has been isolated from M. arbuscula and crambescidins 359 (2) and 431 (3) from M. unguiculata. The chemotaxonomic implications of these findings are discussed.
Asunto(s)
Alcaloides/química , Guanidinas/química , Poríferos/química , Animales , Espectroscopía de Resonancia Magnética , Conformación Molecular , Espectrometría de Masa Bombardeada por Átomos Veloces , Espectrofotometría UltravioletaRESUMEN
Two new macrolide derivatives, madangolide (2) and laingolide A (3), have been isolated from the cyanobacterium Lyngbya bouillonii, collected in Papua New Guinea. Their structures (without stereochemistry) have been established by detailed high-field 1D and 2D NMR studies and, in the case of 3, by comparison with the spectroscopic data of laingolide (1), previously isolated from the same organism.
RESUMEN
A toxic cyanobacterial bloom dominated by Microcystis aeruginosa occurred in 1995 in three adjacent ponds near Liège (Belgium) where at the same time conspicuous bird deaths were observed. The toxicity assay using primary rat hepatocytes indicated a high hepatoxicity. A 4 h incubation yielded a LD50 of 0.23 mg bloom material (dry weight)/ml cell culture medium. Toxicity was due to hepatotoxins of the microcystin class, microcystin-LR and-RR being the major microcystins present as determined by RP-HPLC absorption spectra, 1H NMR, and ESMS spectra. Additionally, the bloom sample contained small amounts of microcystin-YR. The microcystin content of the dry bloom biomass was 870 micrograms/g (on the basis of the hepatotoxicity assay) and 556 micrograms/g (on the basis of the RP-HPLC peak area). A higher yield of microcystins was obtained by acetic acid extraction instead of methanol extraction, whereas different extraction temperatures (20 degrees C, 40 degrees C) had no effect on the yield.
Asunto(s)
Cianobacterias/metabolismo , Agua Dulce/microbiología , Péptidos Cíclicos/análisis , Péptidos Cíclicos/toxicidad , Animales , Bélgica , Carcinógenos/toxicidad , Línea Celular , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Hígado/citología , Hígado/efectos de los fármacos , Microcistinas , Péptidos Cíclicos/química , Péptidos Cíclicos/aislamiento & purificación , Ratas , Contaminantes del Agua/análisisRESUMEN
Fractionation of the MeOH extract of the sponge Plakortis sp. collected around the Amirantes Islands yielded four novel polyketides (4-7). The structures have been established by a detailed highfield 2D NMR study.
Asunto(s)
Antineoplásicos/aislamiento & purificación , Dioxanos/aislamiento & purificación , Furanos/aislamiento & purificación , Poríferos/química , Animales , Antineoplásicos/farmacología , Antineoplásicos/toxicidad , Artemia , Dioxanos/farmacología , Dioxanos/toxicidad , Ensayos de Selección de Medicamentos Antitumorales , Furanos/farmacología , Furanos/toxicidad , Dosificación Letal Mediana , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Espectrofotometría Infrarroja , Espectrofotometría UltravioletaRESUMEN
Larval haemolymph of Neobellieria bullata (Insecta, Diptera) is highly toxic to adults of the same species: injection causes instant paralysis to death. Referring to their dramatic effect in adult insects the responsible compounds were designated paralysins. Two paralysins, soluble in organic solvents and heat stable, were chromatographically purified to homogeneity. They were identified by use of mass spectrometry and nuclear magnetic resonance respectively as beta-alanine-tyrosine (beta-Ala-Tyr) and as 3-hydroxy-kynurenine (3-HK). The quantities of beta-Ala-Tyr and 3-HK in the insect appear to increase steadily during larval development, with peak values prior to the pupal stage. These findings may contribute to a better understanding of some aspects of the process of insect metamorphosis. Orienting experiments in mammals suggest that both compounds, when injected intraspinally, are also neurotoxic to rats. In addition, cytotoxicity tests revealed that 3-HK, but not beta-Ala-Tyr is toxic to human neuroblastoma cells, rat primary cortex neurons as well as to rat glial cells.
Asunto(s)
Dipéptidos/aislamiento & purificación , Dipéptidos/toxicidad , Dípteros/química , Quinurenina/análogos & derivados , Neurotoxinas/aislamiento & purificación , Neurotoxinas/toxicidad , Parálisis/inducido químicamente , Animales , Línea Celular , Células Cultivadas , Cromatografía Líquida de Alta Presión , Dípteros/efectos de los fármacos , Dípteros/crecimiento & desarrollo , Hemolinfa/química , Humanos , Quinurenina/aislamiento & purificación , Quinurenina/toxicidad , Larva/química , Metamorfosis Biológica/efectos de los fármacos , Neuroglía/efectos de los fármacos , Neuronas/efectos de los fármacos , Ratas , Espectrometría de Masa Bombardeada por Átomos Veloces , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
New inhibitors of the Na+-I- cotransporter of the thyroid in bovine thyroid slices and in bovine plasma membrane vesicles have been investigated. They include: (1) econazole; (2) 5-(N,N-hexamethylene)amiloride (HMA); and (3) dysidenin. In both systems, the kinetics of iodide transport yielded apparent Km values of 39 and 14 microM respectively. The possible interaction of each of these inhibitors with the iodide site of the Na+-I- cotransporter was tested by performing detailed transport kinetics analysis at varying iodide concentrations and at 150 mM NaCl. Econazole induced a non-competitive inhibition while dysidenin and HMA gave a mixed type of inhibition. The Ki values for dysidenin and econazole, computed from Dixon plots, were 5 and 2 microM respectively while the Ki value for HMA could not be determined. Each inhibition was reversible, indicating the absence of covalent binding of the inhibitor to the Na+-I- cotransporter.
Asunto(s)
Proteínas Portadoras/antagonistas & inhibidores , Proteínas de la Membrana/antagonistas & inhibidores , Simportadores , Glándula Tiroides/metabolismo , Amilorida/análogos & derivados , Amilorida/farmacología , Animales , Transporte Biológico/efectos de los fármacos , Bovinos , Membrana Celular/metabolismo , Econazol/farmacología , Yoduros/metabolismo , Radioisótopos de Yodo , Cinética , Liposomas/metabolismo , Toxinas Marinas , Tiazoles/farmacologíaRESUMEN
8-Hydroxygeraniol and its 8-O-ß-D-glucoside have been found as trace components in the defensive secretions ofPlagiodera versicolora andGastrophysa viridula larvae. This discovery supports the hypothesis that the evolution of the utilization of plant precursors by some chrysomelid species was favored by the plesiomorphic occurrence of aß-glucosidase and an oxidase in the defensive secretion of iridoid-producing species.
RESUMEN
Four pentacyclic guanidine derivatives (crambescidin 800 [5], crambescidin 816 [6], isocrambescidin 800 [9], and crambine [10]) related to ptilomycalin A [11] have been isolated from the Mediterranean sponge Crambe crambe. Isocrambescidin 800 and crambidine are new derivatives, the structures of which have been determined on the basis of their spectral properties. The absolute configuration of crambescidin 816 at the stereogenic center C-43 has been determined by applying Mosher's method. Pharmacological and biological activities of the Crambe crambe alkaloids are reported. In particular, crambescidin 816 was found to have a potent Ca++ antagonist effect and to inhibit the acetylcholine-induced contraction of guinea pig ileum at very low concentrations.
Asunto(s)
Alcaloides/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Poríferos/química , Compuestos de Espiro/farmacología , Acetilcolina/farmacología , Alcaloides/química , Alcaloides/aislamiento & purificación , Animales , Calcio/metabolismo , Cobayas , Íleon/efectos de los fármacos , Técnicas In Vitro , Espectroscopía de Resonancia Magnética , Masculino , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Espectrofotometría Ultravioleta , Compuestos de Espiro/química , Compuestos de Espiro/aislamiento & purificación , Células Tumorales CultivadasRESUMEN
(6R*)-[(2S*)-2-hydroxyheneicos-12-enyl]-5,6-dihydro-2H-pyran-2-one (1) degree is the major constituent of the secretion of freshly dissected Dufour's gland of the urticating ant Tetramorium aculeatum. In solution, compound 1 is slowly transformed into (1S*,5R*,7S*)-7-(nonadec-10-enyl)-2,6-dioxabicyclo[3.3.1] nonan-3-one (2) degrees on standing. The structures of compounds 1 and 2 have been established on the basis of their spectral and chemical properties. Compound 1 could be responsible for the urticating properties of the ant.