Search results for "radical"
showing 10 items of 1401 documents
El crecimiento coartada de ricos
2002
Synthesis of (-)-Cryptopleurine by Combining Gold(I) Catalysis with a Free Radical Cyclization
2015
(R)-(–)-Cryptopleurine, a highly cytotoxic alkaloid found in Cryptocarya and Boehmeria species, was synthesized in high optical purity using a gold(I)-NHC catalyzed cyclization of an unsymmetrical phenanthrene precursor combined with a free radical cyclization to achieve closure of the C-ring.
Synthesis of (-)-Cryptopleurine by Combining Gold(I) Catalysis with a Free Radical Cyclization (Eur. J. Org. Chem. 10/2015)
2015
Magnetic Molecular Conductors Based on Bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) and the Tris(chlorocyananilato)ferrate(III) Complex
2019
Electrocrystallization of the bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) organic donor in the presence of the [Fe(ClCNAn)3]3– tris(chlorocyananilato)ferrate(III) paramagnetic anion in different stoichiometric ratios and solvent mixtures afforded two different hybrid systems formulated as [BEDT-TTF]4[Fe(ClCNAn)3]·3H2O (1) and [BEDT-TTF]5[Fe(ClCNAn)3]2·2CH3CN (2) (An = anilato). Compounds 1 and 2 present unusual structures without the typical segregated organic and inorganic layers, where layers of 1 are formed by Λ and Δ enantiomers of the anionic paramagnetic complex together with mixed-valence BEDT-TTF tetramers, while layers of 2 are formed by Λ and Δ enantiomers of the paramagnetic…
La corrupción institucionalizada
1998
Cultura de la Solidaridad
1998
Use of concentrated fruit juice extracts to improve the antioxidant properties in a soft drink formulation
2023
Three juices obtained respectively from pomegranate, prickly pear and orange fruit were separately concentrated using an innovative technique, that allow to obtain a final product with high content of bioactive compounds and elevate antioxidant activity. The concentrated juices were employed in the formulation of a soft drink to improve its bioactive properties. Despite a low amount of each concentrated juice was used, the experimental soft drink obtained evidenced a high content of total polyphenols. The antioxidant activity detected was similar to that of tea commonly considered a healthy beverage with strong radical scavenging activity. The sensory analysis of the soft drink showed a con…
Epoxidation of stilbene using supported gold nanoparticles: cumyl peroxyl radical activation at the gold nanoparticle surface.
2014
The catalytic epoxidation of cis-stilbene using cumene as a solvent in the presence of supported gold nanoparticles (AuNP) yields a mixture of cis and trans-stilbene oxides. EPR and product distribution studies support a new mechanistic proposal where oxygen centred radicals activate the AuNP surface and form active surface oxygen species responsible for the epoxidation products.
Thermal frontal polymerization with a thermally released redox catalyst
2012
ABSTRACT: We studied thermal frontal polymerization using a re-dox systeminan attempt to lower the temperature of thefrontallypolymerizable system while increasing the front velocity so as toobtain a self-sustaining front in a thinner layer than without theredox components. A cobalt-containing polymer with a meltingpoint of 63 C (Intelimer 6050X11) and cumene hydroperoxidewere used with a triacrylate. The use of the Intelimer decreasedthe front velocity but allowed fronts to propagate in thinner layersand with more filler while still having a pot life of days. Nonplanarmodes of propagation occurred. Fronts propagated faster when6-O-palmitoyl- L -ascorbic acid was used as a reductant. Intere…
Bioactive Constituents of Juniperus turbinata Guss. from La Maddalena Archipelago.
2018
A comprehensive phytochemical study of Juniperus turbinata (Cupressaceae) collected from La Maddalena Archipelago (Sardinia, Italy) is reported. Both the essential oil and the ethanolic extract obtained from the aerial parts were analyzed. The essential oil appears to belong to a new chemotype compared to other Mediterranean juniper accessions, as it was favored by geographic isolation of the isles. It showed a low content of monoterpene hydrocarbons and -terpineol, ent-manoyl oxide, 1,10-di-epi-cubenol as the major constituents. The ethanolic fraction contained mainly diterpenoids. Among these, 15-formyloxyimbricatolic acid (7) is a new natural product since it has hitherto been obtained o…