Search results for "Lung"
showing 10 items of 2389 documents
Pretreatment T790M mutation detection by ultrasensitive PCR assay as predictor of efficacy in non-small lung cancer (NSCLC) patients treated with 1st…
2019
Personalized intraoperative positive end-expiratory pressure: a further step in protective ventilation
2017
A randomized multicenter trial on a lung ultrasound-guided treatment strategy in patients on chronic hemodialysis with high cardiovascular risk
2021
Lung congestion is a risk factor for all-cause and cardiovascular mortality in patients on chronic hemodialysis, and its estimation by ultrasound may be useful to guide ultrafiltration and drug therapy in this population. In an international, multi-center randomized controlled trial (NCT02310061) we investigated whether a lung ultrasound-guided treatment strategy improved a composite end point (all-cause death, non-fatal myocardial infarction, decompensated heart failure) vs usual care in patients receiving chronic hemodialysis with high cardiovascular risk. Patient-Reported Outcomes (Depression and the Standard Form 36 Quality of Life Questionnaire, SF36) were assessed as secondary outcome…
Phylogeny, epidemiology and microhabitat preferences of lungworms (Pseudaliidae) in cetaceans from teh Western Mediterranean
2023
A pesar de tener una cierta reputación negativa, los parásitos pueden ofrecer una información importante sobre sus hospedadores, habiendo sido reconocidos como herramientas valiosas en varios estudios que investigan el comportamiento (Balbuena y Raga 1991), la salud (Aznar et al. 2005; Gkafas et al. 2020), la dieta (Dailey y Otto 1982), la migración (Ten et al. 2022), la estructura social (Balbuena et al. 1995) o la discriminación de stocks de cetáceos (Aznar et al. 1995). Los helmintos que parasitan a los cetáceos se pueden separar en cuatro grupos distintos: acantocéfalos (20 spp.), cestodos (38 spp.), digeneos (54 spp.) y nematodos (62 spp.). De éstos, los nematodos son los más diversos …
Nucleophilic benzoylation using lithiated methyl mandelate as a synthetic equivalent of the benzoyl carbanion. Oxidative decarboxylation of α-hydroxy…
2001
Abstract The synthesis of alkyl aryl ketones using lithiated methyl mandelate as a synthetic equivalent of the benzoyl carbanion is reported (Umpolung). The methodology involves alkylation of methyl mandelate, hydrolysis of the ester group and oxidative decarboxylation of the resulting α-hydroxyacids. The last step is carried out in a catalytic aerobic way using a Co(III) complex in the presence of pivalaldehyde under very mild and advantageous conditions. The procedure is also applied to methyl mandelates substituted on the aromatic ring.
ChemInform Abstract: Synthesis of Functionalized Indoles with an α-Stereogenic Ketone Moiety Through an Enantioselective Friedel-Crafts Alkylation wi…
2010
Chiral complexes of BINOL-based ligands with hafnium tert-butoxide catalyze the enantioselective Friedel-Crafts alkylation of indoles with (E)-1,4-diaryl-2-butene-1,4-diones at room temperature, with good yields and ee up to 94%. Hafnium(IV) was found to be a more effective Lewis acid than other frequently used metal ions such as titanium(IV) or zirconium(IV). Unlike the enantioselective Friedel-Crafts alkylation of indoles with α,β-unsaturated compounds where the stereogenic center is generated in the β-position to a carbonyl group, the Friedel-Crafts alkylation with 2-butene-1,4-diones described here generates an α-stereogenic center with respect to one of the carbonyl groups. This can be…
Understanding the mechanism of the N-heterocyclic carbene-catalyzed ring-expansion of 4-formyl-β-lactams to succinimide derivatives
2009
The mechanism of the N-heterocyclic carbene (NHC)-catalyzed ring-expansion of 4-formyl-β-lactams to succinimides has been studied using DFT methods at the B3LYP/6-31G∗∗ level. The first step is the nucleophilic attack of NHC to the aldehyde to yield the zwitterionic intermediate, which by a proton-transfer process affords the Breslow intermediate. The lactam N–C breaking bond in this intermediate yields an enol-amidate, which by a keto–enol type equilibrium becomes the ketone form. The subsequent ring-closure achieved by the nucleophilic attack of the amidate to carbonyl carbon allows the formation of the five-membered ring. Finally, elimination of NHC affords the succinimide. Analysis of t…
Synthesis of Functionalized Indoles with an α-Stereogenic Ketone Moiety Through an Enantioselective Friedel-Crafts Alkylation with (E)-1,4-Diaryl-2-b…
2009
Chiral complexes of BINOL-based ligands with hafnium tert-butoxide catalyze the enantioselective Friedel-Crafts alkylation of indoles with (E)-1,4-diaryl-2-butene-1,4-diones at room temperature, with good yields and ee up to 94%. Hafnium(IV) was found to be a more effective Lewis acid than other frequently used metal ions such as titanium(IV) or zirconium(IV). Unlike the enantioselective Friedel-Crafts alkylation of indoles with α,β-unsaturated compounds where the stereogenic center is generated in the β-position to a carbonyl group, the Friedel-Crafts alkylation with 2-butene-1,4-diones described here generates an α-stereogenic center with respect to one of the carbonyl groups. This can be…
ChemInform Abstract: Nucleophilic Benzoylation Using Lithiated Methyl Mandelate as a Synthetic Equivalent of the Benzoyl Carbanion. Oxidative Decarbo…
2010
Abstract The synthesis of alkyl aryl ketones using lithiated methyl mandelate as a synthetic equivalent of the benzoyl carbanion is reported (Umpolung). The methodology involves alkylation of methyl mandelate, hydrolysis of the ester group and oxidative decarboxylation of the resulting α-hydroxyacids. The last step is carried out in a catalytic aerobic way using a Co(III) complex in the presence of pivalaldehyde under very mild and advantageous conditions. The procedure is also applied to methyl mandelates substituted on the aromatic ring.
One-Pot Synthesis of (±)-Crispine A and Its C-Ring-Substituted Analogs
2006
A straightforward access to crispine A and C-ring-substituted analogs by 1,4-addition of a deprotonated α-amino nitrile to α,β-unsaturated carbonyl compounds is described. If the reduction step is omitted, substituted 5,6-dihydropyrrolo[2,1-a]isoquinolines can be obtained. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)