Search results for "Center"

showing 10 items of 1724 documents

ChemInform Abstract: A Versatile Approach to CF3-Containing 2-Pyrrolidones by Tandem Michael Addition-Cyclization: Exemplification in the Synthesis o…

2016

The synthesis of new fluorinated pyrrolidones starting from unprotected amino esters and amino nitriles through a Michael addition-lactamization sequence is described. The resulting CF3 -containing building blocks, bearing a quaternary stereogenic center adjacent to the fluorinated group, have been converted into amino pyrrolidines that display potent β-secretase 1 (BACE1) inhibitory activity. This work constitutes an example of selective fluorination as a valid strategy for the modulation of physicochemical and biological properties of lead compounds in drug discovery.

Amidinechemistry.chemical_compoundTandemchemistryAmino estersDrug discoveryBiological propertyMichael reactionSequence (biology)General MedicineCombinatorial chemistryStereocenterChemInform
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Gold catalyzed stereoselective tandem hydroamination–formal aza-Diels–Alder reaction of propargylic amino esters

2013

A gold-catalyzed tandem intramolecular hydroamination-formal aza-Diels-Alder reaction of propargylic amino esters is described. The overall process leads to the formation of a tetracyclic framework as a single diastereoisomer, with the creation of four bonds and five stereocenters.

Amino estersChemistryStereochemistryMetals and AlloysDiastereomerGeneral ChemistryCatalysisSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsStereocenterCatalysisIntramolecular forceMaterials ChemistryCeramics and CompositesStereoselectivityAza-Diels–Alder reactionHydroaminationChemical Communications
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ChemInform Abstract: Gold-Catalyzed Tandem Hydroamination/Formal Aza-Diels-Alder Reaction of Homopropargyl Amino Esters: A Combined Computational and…

2015

Under optimized conditions, the title reaction leads to formation of a tetracyclic nitrogen-containing framework with generation of 4 bonds and 5 stereocenters.

Amino estersTandemChemistryAza-Diels–Alder reactionGeneral MedicineHydroaminationCombinatorial chemistryCatalysisStereocenterChemInform
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CAD-R. Cuestionario de afrontamiento al dolor crónico: análisis factorial confirmatorio. ¿Hay diferencias individuales en sexo, edad y tipo de dolor?

2017

espanolRESUMEN Introduccion: Se presenta una revision del CAD-R (Cuestionario de afrontamiento al dolor reducido) (1) en una muestra de 4.389 pacientes diagnosticados con dolor cronico derivada de un estudio multicentrico de toda Espana (2). Material y metodo: Se analiza la estructura factorial mediante analisis factorial exploratorio (AFE) y confirmatorio (AFC), asi como la fiabilidad (consistencia interna y test retest a los tres meses, esta ultima sobre 2.825 pacientes). Se ponen a prueba cuatro modelos constatando que las estrategias de primer orden correlacionadas son las que aportan mejores indices de ajuste. Resultados: Tanto los indices de consistencia interna como los test-retest r…

Analisis factorialAFCAnesthesiology and Pain MedicineMulticenter studyInternal consistencydolorPsychologyHumanitiesevaluacióndiferencias individualesCAD-Rafrontamiento
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Dynamics of F-center annihilation in thermochemically reduced MgO single crystals

2001

Optical absorption measurements were used to monitor the thermal annihilation of oxygen vacancies (F-centers) in thermochemically reduced MgO crystals. The annihilation characteristics were sample-dependent and varied strongly with the F-center concentration. Different mechanisms for the destruction of F centers are suggested depending on their concentration.

AnnihilationAbsorption spectroscopyF-Centerbusiness.industryChemistryAnnealing (metallurgy)Analytical chemistryInfrared spectroscopychemistry.chemical_elementGeneral ChemistryCondensed Matter PhysicsOxygenOpticsThermalMaterials ChemistrybusinessSolid State Communications
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Switchable Access to Different Spirocyclopentane Oxindoles by N-Heterocyclic Carbene Catalyzed Reactions of Isatin-Derived Enals and N-Sulfonyl Ketim…

2017

A novel NHC-catalyzed annulation protocol for the asymmetric synthesis of biologically important β-lactam fused spirocyclopentane oxindoles with four contiguous stereocenters, including two quaternary carbon centers, was developed. Alternatively, spirocyclopentane oxindoles containing an enaminone moiety can be achieved using the same starting materials, isatin-derived enals, and N-sulfonyl ketimines, in the presence of a slightly different NHC catalytic system. This switchable annulation strategy enables the selective assembly of both heterocyclic scaffolds with good yields and excellent enantioselectivities for a broad range of substrates.

Annulationasymmetric synthesis010402 general chemistry01 natural sciencesCatalysisStereocenterchemistry.chemical_compoundkatalyytitMoietyOrganic chemistryorganocatalysisN-heterocyclic carbenesheterosykliset yhdisteetspiro-compoundsta116Sulfonylchemistry.chemical_classificationkemiallinen synteesiheterocycles010405 organic chemistryIsatinEnantioselective synthesisGeneral ChemistryGeneral Medicine0104 chemical scienceschemistryOrganocatalysisCarbeneAngewandte Chemie
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Antiretroviral genotypic resistance in plasma RNA and whole blood DNA in HIV-1 infected patients failing HAART

2008

The extent to which HIV-1 proviral DNA mutations cause clinically relevant antiretroviral resistance is still controversial. Paired plasma HIV-1 RNA and whole blood DNA were compared in patients failing HAART to investigate if the additional knowledge of archived mutations could improve the selection of potentially active drugs. Seventy-three HIV-1-infected patients with first/second HAART failure were studied before starting a new regimen based on RNA genotyping. Follow-up data after a 12-week therapy were available. DNA genotyping was retrospectively performed on stored whole blood samples and mutational profiles were compared to those from RNA. The mean number of IAS pol mutations was si…

Anti-HIV AgentsDNA Mutational AnalysisMolecular Sequence DataProviral DNAHIV InfectionsHAART failuremedicine.disease_causeDNA Mutational Analysichemistry.chemical_compoundHIV ProteaseProvirusesAntiretroviral Therapy Highly ActiveVirologyDrug Resistance ViralDNA Mutational AnalysismedicineHumansMulticenter Studies as TopicHIV InfectionTreatment FailureGenotypingRandomized Controlled Trials as TopicCOLD-PCRMutationPlasma RNAbiologyProviruseSequence Analysis RNAAnti-HIV AgentRNASequence Analysis DNAbiology.organism_classificationVirologyHIV Reverse TranscriptaseReverse transcriptaseAntiretroviral genotypic resistanceInfectious DiseaseschemistryDNA ViralMutationLentivirusImmunologyHIV-1RNA ViralDNAantiretroviral genotypic resistance; haart failure; hiv-1; plasma rna; proviral dnaHumanJournal of Medical Virology
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Heart Valve Abnormalities in Systemic Sclerosis Patients; A Multicenter Cohort Study and Review of the Literature

2020

Background Systemic sclerosis (SSc) is a chronic autoimmune disease that is characterized by vasculopathy and fibrosis of the skin and visceral organs. Heart valve diseases are poorly described and generally not considered typical of SSc. We aimed to describe valvular abnormalities in a multicenter cohort of SSc patients and to investigate their correlation with SSc features. Methods We recruited 118 consecutive SSc patients (male/female, 14/104; mean age, 55.2 ± 12.1 years) in 3 rheumatology centers in Sicily, Italy, from January to October 2019. Results Mitral and tricuspid valve insufficiency was found in 85% and 91% of patients, respectively; regurgitations were generally mild and never…

Aortic valveAdultMalemedicine.medical_specialtyHeart Valve DiseasesTricuspid stenosisSclerodermaCohort Studies03 medical and health sciences0302 clinical medicineRheumatologyTricuspid Valve InsufficiencyMitralInternal medicineMedicineHumansMulticenter Studies as Topiccardiovascular diseases030212 general & internal medicineHeart valveAortic valveskin and connective tissue diseasesAged030203 arthritis & rheumatologyScleroderma Systemicintegumentary systembusiness.industrySystemicMitral Valve InsufficiencyMiddle Agedmedicine.diseaseValvular diseaseHeart ValvesRheumatologyTricuspid Valve InsufficiencyStenosismedicine.anatomical_structurePulmonary valvecardiovascular systemCardiologySystemic sclerosisFemalebusinessTricuspidCohort study
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Sex-based differences in outcomes with bivalirudin or unfractionated heparin for transcatheter aortic valve replacement: Results from the BRAVO-3 ran…

2016

Background Women comprise almost 50% of patients undergoing transcatheter aortic valve replacement (TAVR) and previous studies have indicated higher rates of procedural complications and bleeding in women compared to men. It is unknown whether men and women demonstrate a differential response to bivalirudin versus unfractionated heparin (UFH) in TAVR. We sought to evaluate outcomes by sex and type of anticoagulant from the Bivalirudin Versus Heparin Anticoagulation in Transcatheter Aortic Valve Replacement (BRAVO-3) trial of transfemoral TAVR. Methods BRAVO-3 was a randomized multicenter trial comparing transfemoral TAVR with bivalirudin versus UFH (31 centers, n = 802). The primary endpoin…

Aortic valvemedicine.medical_specialtymedicine.drug_classmedicine.medical_treatment030204 cardiovascular system & hematology03 medical and health sciences0302 clinical medicineValve replacementInternal medicineMulticenter trialmedicineBivalirudinRadiology Nuclear Medicine and imaging030212 general & internal medicinebusiness.industryAnticoagulantEuroSCOREGeneral Medicinemedicine.diseasemedicine.anatomical_structureAortic valve stenosisCardiologyCardiology and Cardiovascular MedicinebusinessMacemedicine.drugCatheterization and Cardiovascular Interventions
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ETC-1002: A future option for lipid disorders?

2014

ETC-1002 is a new investigational low density lipoprotein cholesterol (LDL-C)-lowering agent (Esperion Therapeutics, Inc.). ETC-1002 is a dicarboxylic acid derivative with a novel mechanism of action targeting two hepatic enzymes - adenosine triphosphate-citrate lyase (ACL) and adenosine monophosphate-activated protein kinase (AMPK), inhibiting sterol and fatty acid synthesis and promoting mitochondrial long-chain fatty acid oxidation. This agent is currently in phase II clinical research. Available data report that ETC-1002 significantly decreased LDL-C levels (up to 32%) in both patients with normal and elevated baseline levels of triglycerides. Such beneficial effect is superior to curre…

Apolipoprotein BLow density lipoprotein cholesterolBlood PressureAMP-Activated Protein Kinaseschemistry.chemical_compoundMiceMulticenter Studies as TopicDicarboxylic AcidsBeta oxidationHypolipidemic AgentsRandomized Controlled Trials as TopicHypolipidemic AgentbiologyFatty AcidsHyperlipidemiaTolerabilityLiverlipids (amino acids peptides and proteins)Cardiology and Cardiovascular MedicineAMP-Activated Protein Kinasemedicine.drugHumanmedicine.medical_specialtyStatinmedicine.drug_classHypercholesterolemiaHyperlipidemiasClinical Trials Phase II as TopicInternal medicinemedicineAnimalsHumansFatty acid synthesisApolipoproteins BAnimalBody WeightDicarboxylic AcidAMPKCholesterol LDLAdenosineSterolCardiometabolic riskRatsETC-1002Disease Models AnimalEndocrinologychemistrybiology.proteinATP Citrate (pro-S)-LyaseRatFatty AcidLipid lowering therapy
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