Estudio preliminar para la determinacion de la tasa de transferencia de oxigeno de las barricas de roble

El papel del oxígeno en el vino durante la crianza tradicional en barricas de roble es un aspecto de gran relevancia que sigue siendo objeto de numerosos estudios en la actualidad. En este trabajo se realiza un seguimiento en barricas de roble nuevo (francés y americano), del proceso de entrada de oxígeno que tiene lugar desde que se produce el cierre hermético de una barrica con tapón de silicona de llave. La depresión que se genera en el interior de la barrica es un mecanismo complejo relacionado por una parte con la evaporación hacia el exterior del agua y del alcohol, y por otra, con la entrada de oxígeno, cuantificado por el OTR (Tasa de Transferencia de Oxígeno), que varía en función de las características propias de la barrica (origen, usos, características del vino ... ) y de las condiciones medioambientales y de guarda (temperatura, presión y humedad). En este trabajo se ha cuantificado (tanto en roble francés como en americano) la cantidad de oxígeno que permea a través de la madera y el que penetra a través de las juntas de las uniones de las duelas y los fondos. Los resultados indican la gran variabilidad de resultados en cuanto al OTR, tratándose por tanto de un dato propio de cada barrica que refleja la importancia de la metodología seguida en tonelería con el domado de las duelas y el montado de los fondos, factores importantes en la cuantificación del OTR. En resumen, se puede decir que el OTR de cada barrica es un factor muy importante que se debe conocer y tener en cuenta a la hora de conducir una crianza tradicional en barricas de roble.Ingeniería Agrícola y ForestalMáster en Calidad, Desarrollo e Innovación de Alimentos2022/09/04202

1,3-Dien-5-ynes: Versatile Building Blocks for the Synthesis of Carbo- and Heterocycles

1,3-Dien-5-ynes have been extensively used as starting materials for the synthesis of a wide number of different carbo- and heterocycles. The aim of this review is to give an overview of their utility in organic synthesis, highlighting the variety of compounds that can be directly accessed from single reactions over these systems. Thus, cycloaromatization processes are initially commented, followed by reactions directed toward the syntheses of five-membered rings, other carbocycles and, finally, heterocycles. The diverse methodologies that have been developed for the synthesis of each of these types of compounds from 1,3-dien-5-ynes are presented, emphasizing the influence of the reaction conditions and the use of additional reagents in the outcome of the transformations.Ministerio de Economía y Competitividad (MINECO) and FEDER (CTQ2013-41336-P, CTQ2013- 48937-C2-1-P, and CTQ2014-52488-R), Universidad de Alcalá (CCG2015/EXP-003) and Junta de Castilla y León (BU237U13

Regioselective synthesis of elusive 4,9-Dihydro-1H-Carbazoles by gold-catalyzed cycloisomerization of 3-Allenylmethylindoles

A general and efficient synthesis of 4,9-dihydro- 1H-carbazoles from 3-allenylmethylindoles is reported. The process, catalyzed by a cationic gold(I) complex, involves a formal C2−H bond activation of the indole unit by reaction with the allene. The nature of the substituents at the allylic and terminal positions of the allene moiety has a crucial effect on the regioselectivity of the cyclization, which is also influenced by the catalyst and the solvent employed. Moreover, some evidence of the contribution of different reaction routes is provided, which led us to propose a plausible multipathway mechanism consistent with all of the results described.MICINN and FEDER (CTQ2010-15358 and CTQ2009-09949/BQU) for financial support. E.A. thanks MEC for an FPU predoctoral fellowship. P.G.-G. and M.A.F.-R. thank MICINN for "Juan de la Cierva" and "Ramon y Cajal" contractsThis document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of organic chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher

Gut Microbiota Composition Can Predict Colonization by Multidrug-Resistant Bacteria in SARS-CoV-2 Patients in Intensive Care Unit: A Pilot Study

The SARS-CoV-2 infection has increased the number of patients entering Intensive Care Unit (ICU) facilities and antibiotic treatments. Concurrently, the multi-drug resistant bacteria (MDRB) colonization index has risen. Considering that most of these bacteria are derived from gut microbiota, the study of its composition is essential. Additionally, SARS-CoV-2 infection may promote gut dysbiosis, suggesting an effect on microbiota composition. This pilot study aims to determine bacteria biomarkers to predict MDRB colonization risk in SARS-CoV-2 patients in ICUs. Seventeen adult patients with an ICU stay >48 h and who tested positive for SARS-CoV-2 infection were enrolled in this study. Patients were assigned to two groups according to routine MDRB colonization surveillance: non-colonized and colonized. Stool samples were collected when entering ICUs, and microbiota composition was determined through Next Generation Sequencing techniques. Gut microbiota from colonized patients presented significantly lower bacterial diversity compared with non-colonized patients (p < 0.05). Microbiota in colonized subjects showed higher abundance of Anaerococcus, Dialister and Peptoniphilus, while higher levels of Enterococcus, Ochrobactrum and Staphylococcus were found in non-colonized ones. Moreover, LEfSe analysis suggests an initial detection of Dialister propionicifaciens as a biomarker of MDRB colonization risk. This pilot study shows that gut microbiota profile can become a predictor biomarker for MDRB colonization in SARS-CoV-2 patients.Junta de Andalucía (CTS 164; CV20-77708)Instituto de Salud Carlos III (PI19/01058; PI20/01447Fundación Andaluza de Farmacia Hospitalaria” (3095/2020)

Formal [4 + 1] Cycloadditions of β,β-Diaryl-Substituted ortho-(Alkynyl)styrenes through Gold(I)-Catalyzed Cycloisomerization Reactions

Gold(I)-catalyzed cycloisomerization of β,β-diaryl-o-(alkynyl)- styrenes at 80 °C selectively yields dihydroindeno[2,1-a]indenes in a transformation that encompasses a formal [4 + 1] cycloaddition and takes place through a cascade 5-endo-cyclization−diene activation−iso-Nazarov cyclization. In addition, by performing the reaction at 0 °C, the same substrates exclusively give rise to benzofulvene derivatives, which have also been shown to be intermediates in the formation of the tetracyclics.Junta de Castilla y León (BU237U13) and Ministerio de Economıá y Competitividad (MINECO) and FEDER (CTQ2013-48937-C2-1-P

Solvent- and ligand-induced switch of selectivity in gold(I)-catalyzed tandem reactions of 3-propargylindoles

The selectivity of our previously described gold-catalyzed tandem reaction, 1,2-indole migration followed by aura-iso-Nazarov cyclization, of 3-propargylindoles bearing (hetero)aromatic substituents at both the propargylic and terminal positions, was reversed by the proper choice of the catalyst and the reaction conditions. Thus, 3-(inden-2-yl)indoles, derived from an aura-Nazarov cyclization (instead of an aura-iso-Nazarov cyclization), were obtained in moderate to good yields from a variety of 3-propargylindolesMICINN (CTQ2010-15358 and CTQ2009-09949), Junta de Castilla y Leon (BU021A09 and GR-172), MEC (FPU predoctoral fellowship to D.M.), Ramón y Cajal (contract to M.A F R.), Juan de la Cierva (contract to P.G.G.

Gold(I)-catalyzed 6-endo hydroxycyclization of 7-substituted-1,6-enynes

The cyclization of o-(alkynyl)-3-(methylbut-2-enyl)benzenes, 1,6-enynes having a condensed aromatic ring at C3–C4 positions, has been studied under the catalysis of cationic gold(I) complexes. The selective 6-endo-dig mode of cyclization observed for the 7-substituted substrates in the presence of water or methanol giving rise to hydroxy(methoxy)-functionalized dihydronaphthalene derivatives is highly remarkable in the context of the observed reaction pathways for the cycloisomerizations of 1,6-enynes bearing a trisubstituted olefinMinisterio de Ciencia e Innovación (MICINN) and FEDER (CTQ2010-15358

Approaches to the Synthesis of 2,3-Dihaloanilines. Useful Precursors of 4-Functionalized-1H-indoles§

2,3-Dihaloanilines have been proved as useful starting materials for synthesizing 4-halo-1H-indoles. Subsequent or in situ functionalization of the prepared haloindoles allows the access to a wide variety of 2,4- or 2,3,4-regioselectively functionalized indoles in good overall yields. As no efficient synthetic routes to 2,3-dihaloanilines have been described in the literature, different approaches to the preparation of these 1,2,3-functionalized aromatic precursors are now presented. The most general one involves a Smiles rearrangement from the corresponding 2,3-dihalophenols and allows the preparation of 2,3-dihaloanilides in a straightforward and synthetically useful manner.Ministerio de Ciencia e Innovacion (MICINN) and FEDER (CTQ2010-15358) and Junta de Castilla y Leon (BU021A09 and GR-172) for financial support. V.G. thanks Ministerio de Educacion y Ciencia for a MEC-FPU predoctoral fellowship. P.G.-G. and M.A.F.-R. thank MICINN for "Juan de la Cierva" and "Ramon y Cajal" contracts.This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of organic chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher

Straightforward Synthesis of Dihydrobenzo[a]fluorenes through Au(I)-Catalyzed Formal [3 + 3] Cycloadditions

Dihydrobenzo[a]fluorene derivatives have been prepared by a formal intramolecular [3 + 3] cycloaddition of o-alkynylstyrenes bearing a secondary alkyl group at the β-position of the styrene moiety. The process, catalyzed by a cationic gold(I) complex, involves a 1,2-hydride migration as the key step. 6,11-Dihydro-5H-benzo[a]fluorenes could be obtained from the initially generated 6,6a-dihydro-5H-benzo[a]fluorenes by subsequent heating of the reaction mixture under gold(I) or Brønsted acid catalysis or directly by conducting the reactions at high temperatureMICINN and FEDER (CTQ2010-15358 and CTQ2009-09949/BQU) and Junta de Castilla y Leon (BU021A09 and GR-172) for financial support. A.M.S. thanks Junta de Castilla y Leon (Consejeria de Educacion) and Fondo Social Europeo for a PIRTU contract. M.A.R. thanks MEC for a "Young Foreign Researchers" contract (SB2009-0186). P.G.-G. and M.A.F.-R. thank MICINN for "Juan de la Cierva" and "Ramon y Cajal" contractsThis document is the Accepted Manuscript version of a Published Work that appeared in final form in Organic Letters, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/page/policy/articlesonrequest/index.htm

Halocyclization of o-(Alkynyl)styrenes. Synthesis of 3-Halo-1H-indenes

Junta de Castilla y Leon (BU021A09 and GR-172), Ministerio de Educacion y Ciencia (MEC), FEDER (CTQ2007-61436/BQU and CTQ2009-09949/BQU), MEC (FPU grant), Juan de la Cierva, Ramon y Cajal and "Young Foreign Researchers" (SB2009-0186) contract