Search results for "reactions"

Measurement of the low-energy antideuteron inelastic cross section

2020

In this Letter, we report the first measurement of the inelastic cross section for antideuteron-nucleus interactions at low particle momenta, covering a range of $0.3 \leq p < 4$ GeV/$c$. The measurement is carried out using p-Pb collisions at a center-of-mass energy per nucleon-nucleon pair of $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV, recorded with the ALICE detector at the CERN LHC and utilizing the detector material as an absorber for antideuterons and antiprotons. The extracted raw primary antiparticle-to-particle ratios are compared to the results from detailed ALICE simulations based on the GEANT4 toolkit for the propagation of antiparticles through the detector material. The analysis of th…

Ionic liquids: a highway with many lanes

Dimethyl 2-(1-methyl-3-oxo-1,3-dihydroisobenzofuran-1-yl)malonate

2020

In this work we report a facile access to a 3,3-disubstituted isobenzofuranone by tandem addition/cyclization reaction to methyl 2-acetylbenzoate in the presence of dimethyl malonate, under basic conditions.

Stereoselective Synthesis of Spiro-Decalin Oxindole Derivatives via Sequential Organocatalytic Michael-Domino Michael/Aldol Reaction.

2022

A highly stereoselective procedure for the synthesis of spiro-polycyclic oxindoles bearing five contiguous stereogenic centers including two tetrasubstituted carbons has been developed. Under sequential organocatalysis performed by a pyrrolidine-based organocatalyst and DBU, a highly atom-economical Michael–domino Michael/aldol reaction sequence was optimized, yielding variously functionalized spiro-decalin oxindoles with excellent stereoselectivity (>99:1 dr, up to 92% ee). peerReviewed

Angular Regioselectivity in the Reactions of 2-Thioxopyrimidin-4-ones and Hydrazonoyl Chlorides : Synthesis of Novel Stereoisomeric Octahydro[1,2,4]t…

2020

The regioselective synthesis of cis and trans stereoisomers of variously functionalized octahydro[1,2,4]triazolo[4,3-a]quinazolin-5-ones was performed. The 2-thioxopyrimidin-4-ones used in the synthesis reacted with hydrazonoyl chlorides in a regioselective manner to produce the angular regioisomers [1,2,4]triazolo[4,3-a]quinazolin-5-ones rather than the linear isomers [1,2,4]triazolo[4,3-a]quinazolin-5-ones. The synthesis process took place with electronic control. The angular regiochemistry of the products was confirmed by X-ray experiments and two-dimensional NMR studies.

Cyclic Sulfoximine and Sulfonimidamide Derivatives by Copper‐Catalyzed Cross‐Coupling Reactions with Elemental Sulfur

2023

Copper-catalyzed cross-coupling reactions of α-bromoaryl NH-sulfoximines with elemental sulfur lead to benzo[d][1,3,2]dithiazole-1-oxides, which represent a new class of three-dimensional heterocycles. The reactions proceed under mild conditions showing good functional group and heterocycle tolerance. By imination/oxidation, the initial cross-coupling products can be converted to unprecedented cyclic sulfonimidamides derivatives. Furthermore, a seven-membered heterocycle was obtained by a ruthenium-catalyzed ring-expansion with ethyl propiolate. peerReviewed

Synthesis of Polycyclic Indolines utilizing a reduction/cyclization cascade reaction

2021

Subsequent reduction and dearomatizing cyclization reactions open up an entry into the synthesis of novel N-fused polycyclic indolines. The dearomatizing cyclization as key step of the sequence proceeds well with Cu(OTf)2 or TfOH as catalyst. At elevated temperature reduction of nitro-substituted precursors with iron under acidic conditions affords a broad variety of polycyclic indolines directly in a two-step cascade reaction in good to excellent yields. Using the developed protocol, the alkaloids Tryptanthrin and Phaitanthrin C have been prepared. peerReviewed

Cognitive changes in reader-evoked frames : culture-specific references in Edna O'Brien's The Country Girls and its Finnish translation

2005

Immunoaffinity purification and characterization of mitochondrial membrane-bound D-3-hydroxybutyrate dehydrogenase from Jaculus orientalis.

2008

Abstract Background The interconversion of two important energy metabolites, 3-hydroxybutyrate and acetoacetate (the major ketone bodies), is catalyzed by D-3-hydroxybutyrate dehydrogenase (BDH1: EC 1.1.1.30), a NAD+-dependent enzyme. The eukaryotic enzyme is bound to the mitochondrial inner membrane and harbors a unique lecithin-dependent activity. Here, we report an advanced purification method of the mammalian BDH applied to the liver enzyme from jerboa (Jaculus orientalis), a hibernating rodent adapted to extreme diet and environmental conditions. Results Purifying BDH from jerboa liver overcomes its low specific activity in mitochondria for further biochemical characterization of the e…

SIRM-SIAAIC consensus, an Italian document on management of patients at risk of hypersensitivity reactions to contrast media

2020

Abstract Hypersensitivity reactions (HRs) to contrast media (CM) can be distinguished in immune-mediated (including allergic reactions) and non-immune-mediated reactions, even if clinical manifestations could be similar. Such manifestations range from mild skin eruptions to severe anaphylaxis, making it important for radiologists to know how to identify and manage them. A panel of experts from the Società Italiana di Radiologia Medica e Interventistica (SIRM) and the Società Italiana di Allergologia, Asma e Immunologia Clinica (SIAAIC) provided a consensus document on the management of patients who must undergo radiological investigations with CM. Consensus topics included: the risk stratif…