Recent advances in the catalytic asymmetric 1,3-dipolar cycloaddition of azomethine ylides

Catalytic asymmetric 1,3-dipolar cycloadditions of azomethine ylides have turned out to be one of the most efficient methods for the preparation of enantioenriched pyrrolidines. The past decade has witnessed the development of a bunch of well-defined catalytic systems capable of affording excellent diastereo and enantioselectivities. Recently, a great effort has been focused on expanding the scope of the cycloaddition with regard to both reaction partners. In this review, we will discuss important advances that have been reported in this area since 2011The Ministerio de Economía y Competitividad (MINECO, project CTQ2012-3579) and Consejería de Educación de la Comunidad de Madrid (programme AVANCAT; S2009/PPQ-1634

Metal-free solvent promoted oxidation of benzylic secondary amines to nitrones with H202

An environmentally benign protocol for the generation of nitrones from benzylic secondary amines via catalyst-free oxidation of secondary amines using H2O2 in MeOH or CH3CN is described. This methodology provides a selective access to a variety of C-aryl nitrones in yields of 60 to 93%. Several studies have been performed to shed light on the reaction mechanism and the role of the solventWe thank FEDER/Ministerio de Ciencia, Innovación y Universidades−Agencia Estatal de Investigación (Grant PGC2018-098660-B-I00) and CAPES (Finance Code 001), CNPq (310514/2018-5), FAPEMIG for financial suppor

Catalytic asymmetric synthesis of diazabicyclo[3.1.0]hexanes by 1,3-dipolar cycloaddition of azomethine ylides with azirines

Substituted 1,3-diazabicyclo[3.1.0]hexanes with two contiguous quaternary stereocentres are readily prepared by catalytic asymmetric [3+2] cycloaddition of α-substituted iminoesters with azirines. High diastereoselectivities and enantioselectivities (up to 98% ee) are achieved using CuI/(R)-Fesulphos as the catalytic systemWe thank the Spanish Ministerio de Economía, Industria y Competitividad (Grant CTQ2015-66954-P, MINECO/FEDER, UE) and FEDER/Ministerio de Ciencia, Innovación y Universidades – Agencia Estatal de Investigación (Grant PGC2018-098660-B-I00) for financial suppor

Cu(I)‑Catalyzed Asymmetric [3 + 2] Cycloaddition of Azomethine 2 Ylides with Cyclobutenones

Al texto del artículo le acompaña el material complementarioThe catalytic asymmetric 1,3-dipolar cycloaddition of cyclobutenones with azomethine ylides provides straightforward access to densely substituted 3-azabicyclo[3.2.0]heptanes. In the presence of CuI/(R)-Fesulphos as the catalytic system, high levels of diastereoselectivity and enantioselectivity were achieved (up to 98% enantiomeric excess (ee)).Financial support of this work by the Ministerio de Economía, Industria y Competitividad and Fondo Europeo de Desarrollo Regional (Project Nos. CTQ2012-35790 MINECO and CTQ2015-66954-P MINECO/FEDER, UE) is gratefully acknowledged. A.P. thanks the MICINN for a predoctoral fellowship. J.C. thanks the MECD for a FPU predoctoral fellowshi

Aldehydes as photoremovable directing groups: synthesis of pyrazoles by a photocatalyzed [3+2] cycloaddition/norrish type fragmentation sequence

A straightforward methodology for the regioselective synthesis of pyrazoles has been developed by a domino sequence based on a photoclick cycloaddition followed by a photocatalyzed oxidative deformylation reaction. Distinguishing features of this protocol include an unprecedented photoredox-catalyzed Norrish type fragmentation under green-light irradiation and the use of α,β-unsaturated aldehydes as synthetic equivalents of alkynes, where the aldehyde is acting as a novel photoremovable directing groupThis work was supported by the MINECO (CTQ2014-53894-R and CTQ2017-85454-C2-2-P) and FEDER/MICIU (PGC2018-098660-B-I00) of Spain. L.O.-R. thanks MINECO for a FPI fellowship, and A.P.-E. thanks CAM for a postdoctoral fellowshi

Catalytic Asymmetric Synthesis of Bicycloprolines by a 1,3-Dipolar Cycloaddition/Intramolecular Alkylation Strategy

This document is the Accepted Manuscript version of a Published Work that appeared in final form inJournal of Organic Chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/acs.joc.6b01100 to Published Work, see http://pubs.acs.org/page/policy/articlesonrequest/index.htmlThe diastereoselective one-pot synthesis of hexahydrocyclopenta [b] pyrrole derivatives (bicycloprolines) has been achieved by base-mediated reactions of (E)-tert-butyl 6-bromo-2-hexenoate with α-imino esters. The catalytic asymmetric version of this process has been efficiently achieved using the CuI/(R)-DTBM-Segphos complex as a catalyst following a two-step 1,3-dipolar cycloaddition/intramolecular alkylation sequence.Financial support of this work by the Ministerio de Economía y Competitividad and Fondo Europeo de Desarrollo Regional (MINECO CTQ2012-35790 and MINECO/FEDER CTQ2015-66954-P) are gratefully acknowledged. M.G.-E. and A.P.-E. thank the MICINN for predoctoral fellowship

Enantioselective transformations of 5-hydroxymethylfurfural via catalytic asymmetric 1,3-dipolar cycloaddition of azomethine ylides

A catalytic asymmetric 1,3-dipolar cycloaddition between iminoesters derived from 5-hydroxymethylfurfural (HMF) and different activated alkenes is reported. Excellent levels of diastereo and enantioselectivity were obtained when Fesulphos/CuI complex was used as catalyst. This metodology provides an effective and sustainable access to challenging enantioenriched heterocyclic scaffolds and represents one of the rare examples of catalytic asymmetric transformations using HMF as a starting materialPID2020-113059GB-C22, B2017/BMD- 3867 RENIMC

Blunt traumatic aortic injuries of the ascending aorta and aortic arch: a clinical multicentre study

[Abstract] Objective. To report the clinical and radiological characteristics, management and outcomes of traumatic ascending aorta and aortic arch injuries. Methods. Historic cohort multicentre study including 17 major trauma patients with traumatic aortic injury from January 2000 to January 2011. Results. The most common mechanism of blunt trauma was motor-vehicle crash (47%) followed by motorcycle crash (41%). Patients sustaining traumatic ascending aorta or aortic arch injuries presented a high proportion of myocardial contusion (41%); moderate or greater aortic valve regurgitation (12%); haemopericardium (35%); severe head injuries (65%) and spinal cord injury (23%). The 58.8% of the patients presented a high degree aortic injury (types III and IV). Expected in-hospital mortality was over 50% as defined by mean TRISS 59.7 (SD 38.6) and mean ISS 48.2 (SD 21.6) on admission. Observed in-hospital mortality was 53%. The cause of death was directly related to the ATAI in 45% of cases, head and abdominal injuries being the cause of death in the remaining 55% cases. Long-term survival was 46% at 1 year, 39% at 5 years, and 19% at 10 years. Conclusions. Traumatic aortic injuries of the ascending aorta/arch should be considered in any major thoracic trauma patient presenting cardiac tamponade, aortic valve regurgitation and/or myocardial contusion. These aortic injuries are also associated with a high incidence of neurological injuries, which can be just as lethal as the aortic injury, so treatment priorities should be modulated on an individual basis

Hybridizing Feature Selection and Feature Learning Approaches in QSAR Modeling for Drug Discovery

Quantitative structure–activity relationship modeling using machine learning techniques constitutes a complex computational problem, where the identification of the most informative molecular descriptors for predicting a specific target property plays a critical role. Two main general approaches can be used for this modeling procedure: feature selection and feature learning. In this paper, a performance comparative study of two state-of-art methods related to these two approaches is carried out. In particular, regression and classification models for three different issues are inferred using both methods under different experimental scenarios: two drug-like properties, such as blood-brain-barrier and human intestinal absorption, and enantiomeric excess, as a measurement of purity used for chiral substances. Beyond the contrastive analysis of feature selection and feature learning methods as competitive approaches, the hybridization of these strategies is also evaluated based on previous results obtained in material sciences. From the experimental results, it can be concluded that there is not a clear winner between both approaches because the performance depends on the characteristics of the compound databases used for modeling. Nevertheless, in several cases, it was observed that the accuracy of the models can be improved by combining both approaches when the molecular descriptor sets provided by feature selection and feature learning contain complementary information.Fil: Ponzoni, Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias e Ingeniería de la Computación. Universidad Nacional del Sur. Departamento de Ciencias e Ingeniería de la Computación. Instituto de Ciencias e Ingeniería de la Computación; ArgentinaFil: Sebastián Pérez, Víctor. Consejo Superior de Investigaciones Científicas. Centro de Investigaciones Biológicas; EspañaFil: Requena Triguero, Carlos. Consejo Superior de Investigaciones Científicas. Centro de Investigaciones Biológicas; EspañaFil: Roca, Carlos. Consejo Superior de Investigaciones Científicas. Centro de Investigaciones Biológicas; EspañaFil: Martínez, María Jimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias e Ingeniería de la Computación. Universidad Nacional del Sur. Departamento de Ciencias e Ingeniería de la Computación. Instituto de Ciencias e Ingeniería de la Computación; ArgentinaFil: Cravero, Fiorella. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Diaz, Monica Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Páez, Juan A.. Consejo Superior de Investigaciones Científicas. Instituto de Química Médica; EspañaFil: Gómez Arrayás, Ramón. Universidad Autónoma de Madrid; EspañaFil: Adrio, Javier. Universidad Autónoma de Madrid; España. Institute for Advanced Research in Chemical Sciences; EspañaFil: Campillo, Nuria E.. Consejo Superior de Investigaciones Científicas. Centro de Investigaciones Biológicas; Españ

Glove perforation and sternal wound infection in open heart surgery

Introducción y objetivos: La perforación de los guantes rompe la barrera entre la microbiota de las manos del cirujano y los tejidos estériles del paciente. El objetivo de este trabajo fue evaluar el efecto de la perforación de los guantes sobre la contaminación de la herida de esternotomía y las complicaciones infecciosas postoperatorias. Métodos: Se realizó un estudio prospectivo en 139 pacientes intervenidos de cirugía cardíaca mediante esternotomía media y en 7 cirujanos. Se evaluaron la presencia y la localización de las perforaciones, y la contaminación de la herida de esternotomía al final de la intervención. Se realizó un seguimiento para detectar complicaciones infecciosas postoperatorias. Resultados: La frecuencia de perforaciones en los guantes fue del 23%, siendo más frecuentes en los dedos índice y pulgar de la mano no dominante. La tasa de contaminación de la herida de esternotomía fue del 7,91%, siendo Staphylococcus epidermidis el microorganismo más frecuente. Ninguno de los pacientes donde se detectó perforación de los guantes o contaminación de la herida quirúrgica desarrolló infección postoperatoria del sitio quirúrgico. Conclusiones: No existe correlación entre perforación de los guantes y la contaminación de la herida de esternotomía ni con la aparición de complicaciones infecciosas postoperatorias. El desarrollo de una infección del sitio quirúrgico es un proceso complejo que depende de muchos otros factores además de los estudiados.Background and objectives: Surgical glove puncture breaks the barrier between the surgeon hands and the patient sterile wound tissues. The purpose of this work was to evaluate the effect of glove perforation on contamination of the sternal wound and postoperative infectious complications. Methods: A prospective study included 139 patients undergoing open heart surgery through a median sternotomy and seven cardiac surgeons. Glove puncture frequency and localization as well as wound contamination were evaluated at the end of the operation. Short and medium-term follow up was carried out to detect surgical site infections. Results: Glove perforation rate was 23% of the samples being more frequent in the index and thumb of the nondominant hand. The rate of contamination of the sternotomy wound was 7.91% being Staphylococcus epidermidis the most frequent microorganism. None of the patients with either glove punctures or wound contamination presented any surgical site infection. Conclusions: There is no correlation between glove perforation and sternal wound contamination and postoperative infectious complications. Surgical site infection is a more complex problem than it seems and depends of many other factors.S