Borane-catalysed Alkyne Hydroboration

Within the past few decades, organoboron compounds have become essential intermediates in organic and medicinal chemistry due to their unique advantages and versatility. Many synthetic approaches have been utilised to prepare these useful compounds, including several catalytic systems and diverse hydroborating agents. The hydroboration of terminal alkynes is one of the more common routes that provides alkenylboron reagents, allowing regio- and stereo-selective installation of the boron. Alcoholysis of phosphine borane complex to generate a new metastable hydroborating agent has been studied. The effect of the alcohol and solvent used in the solvolysis reaction have been determined. The use of halogenated solvents removed the irreproducibility observed when an ethereal solvent is used on its own. Thus having a mixture of both solvents, produces an ideal media to stabilise dialkoxyborane species. All kinetic data obtained are consistent with a direct SN2-like mechanism. A plausible mechanism has been proposed where an inconsistent generation of an ionic active species is likely to be causing the irreproducibility in the kinetic stability of the intermediate HB(OEt) 2. The dicyclohexylborane-catalysed hydroboration of 4-fluoropheny-lacetylene with pinacolborane was used as a benchmark. The kinetic profile for all components, including intermediates and side-products, have also been established by using in situ 19F NMR kinetic analysis and simulation. Isotope entrainment and stoichiometric studies employing isotopic labelling were used to characterise key steps of the borane-catalysed hydroboration reaction. The experimental evidence used to propose a thorough mechanism were also backed up by density functional theory (DFT) calculations. The mechanism includes the first true transborylation step, responsible of the regeneration of the catalyst (HBCy2) via B-C-B transfer of the alkenyl group with retention of (E)-configuration

Prevalencia serológica la enfermedad de newcastle y bronquitis en codornices (coturnix coturnix) en el área metropolitana de cúcuta y municipios aledaños

En los municipios de Cúcuta, Chinácota, Los Patios, Bochalema y Villa del Rosario, un total de 12 granjas fueron estudiadas para determinar la prevalencia de las enfermedades de Newcastle y Bronquitis Infecciosa en codornices, debido a la escasa información que sobre éstas enfermedades en ésta especie. Se determinó una prevalencia serológica de 50.9 % para Newcastle y de 32.7 % para Bronquitis Infecciosa. Por lo que discute la presencia de estas dos entidades en esta región y los posibles mecanismos de control.Palabras Clave: Prevalencia; serología; Newcastle; Bronquitis Infecciosa ; Codornices;(Coturnix cortinix).

Role of age and comorbidities in mortality of patients with infective endocarditis

[Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. [Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. [Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. [Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group

Prevalencia serológica la enfermedad de newcastle y bronquitis en codornices (coturnix coturnix) en el área metropolitana de cúcuta y municipios aledaños

En los municipios de Cúcuta, Chinácota, Los Patios, Bochalema y Villa del Rosario, un total de 12 granjas fueron estudiadas para determinar la prevalencia de las enfermedades de Newcastle y Bronquitis Infecciosa en codornices, debido a la escasa información que sobre éstas enfermedades en ésta especie. Se determinó una prevalencia serológica de 50.9 % para Newcastle y de 32.7 % para Bronquitis Infecciosa. Por lo que discute la presencia de estas dos entidades en esta región y los posibles mecanismos de control.ABSTRACTIn the municipalities of Cúcuta, Chinácota, Los Patios, Bochalema and Villa del Rosario, a total of 12 farm was studied to determine the prevalence of the disease of Newcastle and Infectious Bronchitis in quails, due to the scarce information that it has more than enough these illnesses in this species. A prevalence of 50.9% was determined for Newcastle and of 32.7% for Infectious Bronchitis. For what the presence of these two entities discusses in this region and the possible control mechanisms.

Synthesis of novel tetrahydroindeno[1,2-<i>b</i>]pyrrolidines via Ugi multicomponent and palladium-catalyzed aerobic oxidative cyclization

<p>Novel tetrahydroindeno[1,2-<i>b</i>]pyrrolidines were conveniently prepared in moderate to good yields via a sequential Ugi multicomponent reaction or Staudinger/aza-Wittig/Ugi combination, followed by the palladium-catalyzed aerobic oxidative cyclization of the resulting Ugi adducts.</p

Role of age and comorbidities in mortality of patients with infective endocarditis.

The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups: A total of 3120 patients with IE (1327  There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in th

Contemporary use of cefazolin for MSSA infective endocarditis: analysis of a national prospective cohort

Objectives: This study aimed to assess the real use of cefazolin for methicillin-susceptible Staphylococcus aureus (MSSA) infective endocarditis (IE) in the Spanish National Endocarditis Database (GAMES) and to compare it with antistaphylococcal penicillin (ASP). Methods: Prospective cohort study with retrospective analysis of a cohort of MSSA IE treated with cloxacillin and/or cefazolin. Outcomes assessed were relapse; intra-hospital, overall, and endocarditis-related mortality; and adverse events. Risk of renal toxicity with each treatment was evaluated separately. Results: We included 631 IE episodes caused by MSSA treated with cloxacillin and/or cefazolin. Antibiotic treatment was cloxacillin, cefazolin, or both in 537 (85%), 57 (9%), and 37 (6%) episodes, respectively. Patients treated with cefazolin had significantly higher rates of comorbidities (median Charlson Index 7, P <0.01) and previous renal failure (57.9%, P <0.01). Patients treated with cloxacillin presented higher rates of septic shock (25%, P = 0.033) and new-onset or worsening renal failure (47.3%, P = 0.024) with significantly higher rates of in-hospital mortality (38.5%, P = 0.017). One-year IE-related mortality and rate of relapses were similar between treatment groups. None of the treatments were identified as risk or protective factors. Conclusion: Our results suggest that cefazolin is a valuable option for the treatment of MSSA IE, without differences in 1-year mortality or relapses compared with cloxacillin, and might be considered equally effective