Institute Quimica Organica General IQOG CSIC

San Juan de la Rambla, Spain

Institute Quimica Organica General IQOG CSIC

San Juan de la Rambla, Spain
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Fraser-Reid B.,Natural Products and Glycotechnology Research Institute Inc. | Ganney P.,Natural Products and Glycotechnology Research Institute Inc. | Ramamurty C.V.S.,Natural Products and Glycotechnology Research Institute Inc. | Gomez A.M.,Institute Quimica Organica General IQOG CSIC | Lopez J.C.,Institute Quimica Organica General IQOG CSIC
Chemical Communications | Year: 2013

Strategically derivatized NPOE glycosyl donors, are able to efficiently glycosylate silylated nucleobases under mild conditions, even as low as -78°C if necessary. Ensuring trans-1,2 glycosylation, thus permitting, unlike classical procedures, a Reverse Strategy for the synthesis of ribonucleosides, where glycosylation occurs late, rather than early, and convergency is optimized. © 2013 The Royal Society of Chemistry.


Uriel C.,Institute Quimica Organica General IQOG CSIC | Gomez A.M.,Institute Quimica Organica General IQOG CSIC | Lopez J.C.,Institute Quimica Organica General IQOG CSIC | Fraser-Reid B.,Natural Products and Glycotechnology Research Institute Inc. NPG
Organic and Biomolecular Chemistry | Year: 2012

A branched Man5 oligosaccharide has been synthesized by sequential regioselective glycosylations on a mannose-tetraol with n-pentenyl orthoester glycosyl-donors promoted by NIS/BF3·Et 2O, in CH2Cl2. An extended n-pentenyl chain was incorporated into the tetraol acceptor to facilitate (a) the solubility of the starting tetraol in CH2Cl2, and (b) future manipulations at the reducing end of the Man5 oligosaccharide. © The Royal Society of Chemistry 2012.


Medel S.,CSIC - Institute of Polymer Science and Technology | Bosch P.,CSIC - Institute of Polymer Science and Technology | De La Torre C.,Institute Quimica Organica General IQOG CSIC | Ramirez P.,Institute Quimica Organica General IQOG CSIC
European Polymer Journal | Year: 2014

The synthesis of two new fluorescent hyperbranched polymers with low molecular weight macromolecular skeleton is presented. An experimental approach to obtain fluorescent dansyl derivatives of commercial hydroxyl-terminated hyperbranched polymers (HBPs) have been obtained through click chemistry reactions. Photophysical characterization of the HBP probes compared with their low molecular weight reference compounds shows that the fluorophore in the polymer skeleton behaves as an individual molecule, showing similar emission properties in terms of absorption extinction coefficient, fluorescence quantum yields and position of the fluorescent band. Solvatochromic study of the HBPs in several solvents using ET30, π∗ and SPP scales demonstrates that there is not a loss of sensitivity towards polarity when the sensor moiety is included in the HBP structure. The absence of quenching deactivation processes in these multifunctional sensors has been attributed to their irregular hyperbranched skeleton, in contrast to what occurs in highly regular dendrimeric analogues. The advantage of the oligomeric probes versus the monomeric ones has been checked preparing transparent and sensitive films using the fluorophores as dopants. The swelling kinetics of the films has been monitored by fluorescence and the diffusion coefficient estimated. Negligible extraction of the hyperbranched probes was found for long time immersions of the films in acetonitrile, whereas low molecular weight derivatives showed continuous extraction. © 2014 Elsevier Ltd. All rights reserved.


Dorta E.,Instituto Canario Of Investigaciones Agrarias | Lobo M.G.,Instituto Canario Of Investigaciones Agrarias | Gonzalez M.,Institute Quimica Organica General IQOG CSIC
Plant Foods for Human Nutrition | Year: 2013

The purpose of this study was to analyze the extraction efficiency of antioxidants from mango peel by comparing two techniques: microwave-assisted (MAE) and traditional solvent (TE) extraction. The number of extraction steps, water content in the extractant, peel weight-to-solvent volume ratio in extractions and extraction time all had an influence on obtaining extracts with high antioxidant capacity, but the extraction technique and the water content in the extractant were the factors with the greatest effect. Using three steps, a water content of 50 % in the ethanol:water extractant, an extraction time of 60 min and a weight-to-volume ratio of 1:10 or 1:50 (w/v) led to the highest antioxidant activity and phytochemicals content in extracts. The extraction time needed to extract phytochemicals from mango peel was similar when MAE and TE were used. However, the antioxidant capacity and phytochemical content were around 1.5-6.0 times higher in the extracts obtained by MAE. © 2013 Springer Science+Business Media New York.


Liras M.,Institute Quimica Organica General IQOG CSIC | Liras M.,IMDEA Madrid Institute for Advanced Studies | Iglesias M.,CSIC - Institute of Materials Science | Sanchez F.,Institute Quimica Organica General IQOG CSIC
Macromolecules | Year: 2016

Here we report the design and synthesis of a new conjugated microporous polymer based on a BODIPY dye (CMPBDP) which has shown excellent luminescence properties and an efficient heterogeneous photocatalytic activity. CMPBDP shows high thermal stability and high surface area with microporous size and efficiently catalyzes the selective oxidation of thioanisole into the corresponding sulfoxide via singlet oxygen under visible light (up to 500 nm). The photocatalytic rate of the heterogeneous materials is 4-fold faster that the corresponding soluble (used as reference) under the same reaction conditions and can be reused several times. © 2016 American Chemical Society.


Gamboa-Santos J.,Institute Investigacion En Ciencias Of La Alimentacion Cial Csic Uam | Cristina Soria A.,Institute Quimica Organica General IQOG CSIC | Perez-Mateos M.,Institute Ciencia Y Tecnologia Of Alimentos Y Nutricion Ictan Csic | Carrasco J.A.,Institute Ciencia Y Tecnologia Of Alimentos Y Nutricion Ictan Csic | And 2 more authors.
Food Chemistry | Year: 2013

Vitamin C content and sensorial properties have been evaluated in air-dried carrots previously subjected to different ultrasound (US) or conventional blanching pretreatments. In addition, mass spectral fingerprints obtained by the Headspace ChemSensor System have been evaluated for the first time for classification of carrots according to their processing. Conventional blanching treatments at high temperature gave rise to carrots with retention of vitamin C in the range 37.5-85%, whereas carrots blanched conventionally at 60 °C and by US-probe at temperatures up to 60 and 70 °C showed vitamin C retention values lower than 4%. Regarding sensorial analysis of rehydrated carrots, US-pretreated samples presented acceptable quality, and no statistically significant differences with respect to conventionally blanched carrots, were detected. In spite of this, differentiation of samples processed under comparable intensity conditions and/or with similar composition was possible from their mass spectral fingerprints after chemometric data analysis. © 2012 Elsevier Ltd. All rights reserved.


Gomez A.M.,Institute Quimica Organica General IQOG CSIC | Uriel C.,Institute Quimica Organica General IQOG CSIC | Lobo F.,Institute Quimica Organica General IQOG CSIC | Lopez J.C.,Institute Quimica Organica General IQOG CSIC
Current Organic Synthesis | Year: 2014

Carbohydrates have been recognized as privileged structures for the regio- and stereo-controlled appendage of pharmacophores to generate new derivatives with potential application in drug discovery processes. Even though most of the carbohydrate templates have been generated from pyranoses, other sugar derivatives have also been employed in the assembly of such structures. In this review, attention has been directed to the use of sugar-furanose platforms, and an account of the recent developments in the generation of furanose-based templates aiming at the generation of molecular diversity, including those from our research group, is presented. © 2014 Bentham Science Publishers.


Neves V.C.,University of The Azores | Bried J.,University of The Azores | Gonzalez-Solis J.,University of Barcelona | Roscales J.L.,University of Barcelona | And 2 more authors.
Marine Ecology Progress Series | Year: 2012

Trophic ecology and movements are critical issues for understanding the role of marine predators in food webs and for facing the challenges of their conservation. Seabird foraging ecology has been increasingly studied, but small elusive species, such as those forming the 'little shearwater' complex, remain poorly known. We present the first study on the movements and feeding ecology of the Barolo shearwater Puffinus baroli baroli in a colony from the Azores archipelago (NE Atlantic), combining global location-sensing units, stable isotope analyses of feathers (δ13C and δ15N), stomach flushings and data from maximum depth gauges. During the chick-rearing period, parents visited their nests most nights, foraged mainly south of the colony and fed at lower trophic levels than during the non-breeding period. Squid was the most diverse prey (6 families and at least 10 different taxa), but species composition varied considerably between years. Two squid families, Onychoteuthidae and Argonautidae, and the fish family Phycidae accounted for 82.3% of ingested prey by number. On average, maximum dive depths per foraging trip reached 14.8 m (range: 7.9 to 23.1 m). After the breeding period, birds dispersed offshore in all directions and up to 2500 km from the breeding colony, and fed at higher trophic levels. Overall, our results indicate that the Barolo shearwater is a non-migratory shearwater feeding at the lowest trophic level among Macaronesian seabirds, showing both diurnal and nocturnal activity and feeding deeper in the water column, principally on small schooling squid and fish. These traits contrast with those of 3 other Azorean Procellariiformes (Cory's shearwater Calonectris diomedea, the Madeiran storm-petrel Oceanodroma castro and Monteiro's storm-petrel O. monteiroi), indicating ecological segregation within the Azorean seabird community. © Inter-Research 2012.


Lobo F.,Institute Quimica Organica General IQOG CSIC | Gomez A.M.,Institute Quimica Organica General IQOG CSIC | Miranda S.,Institute Quimica Organica General IQOG CSIC | Lopez J.C.,Institute Quimica Organica General IQOG CSIC
Chemistry - A European Journal | Year: 2014

Novel substrates that combine dicobalt hexacarbonyl propargyl (Nicholas) and pyranose-derived allylic (Ferrier) cations have been generated by treatment of hexacarbonyldicobalt (C-1)-alkynyl glycals with BF3 .Et2O. The study of these cations has resulted in the discovery of novel reaction pathways that have shown to be associated to the nature of O-6 substituent in the starting alkynyl glycals. Accordingly, compounds resulting from ring expansion (oxepanes), ring contraction (tetrahydrofurans), or branched pyranoses, by incorporation of nucleophiles, can be obtained from 6-O-benzyl, 6-hydroxy, or 6-O-silyl derivatives, respectively. The use of a 6-O-allyl alkynyl glycal led to a suitable funtionalized oxepane able to experience an intramolecular Pauson-Khand cyclization leading to a single tricyclic derivative. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Gomez A.M.,Institute Quimica Organica General IQOG CSIC | Lobo F.,Institute Quimica Organica General IQOG CSIC | Uriel C.,Institute Quimica Organica General IQOG CSIC | Lopez J.C.,Institute Quimica Organica General IQOG CSIC
European Journal of Organic Chemistry | Year: 2013

Glycals (1,2-unsaturated, cyclic carbohydrate derivatives) readily undergo (catalyzed) substitution reactions at C-1 accompanied by allylic rearrangement. This reaction, currently named Ferrier rearrangement, or the Ferrier I reaction, has established itself as a useful synthetic tool for carbohydrate transformations. By means of this reaction, glycals can be converted into highly useful 2,3-unsaturated glycosides. This review summarizes recent developments in the use of promoters for the Ferrier rearrangement of O-, N-, C- and S-nucleophiles with glycals. The (catalyzed) substitution of glycals at C-1, accompanied by allylic rearrangement to give unsaturated glycosides, is known as Ferrier rearrangement, or the Ferrier I reaction. Recent developments in this rearrangement have involved evaluation of new homogeneous and heterogeneous catalysts, as well as its application to nucleophiles other than oxygenated ones (e.g., C-, N-, and S-nucleophiles). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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