114 research outputs found

    Prothymosin α receptors on peripheral blood mononuclear cells

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    Abstract125I-Labeled prothymosin α (ProTα) was used to study the presence and characteristics of receptors for ProTα on human peripheral blood mononuclear cells (PBMC). The kinetics of 125I-ProTα binding to PBMC was fast at 37°C, whilst it required 50 min to reach equilibrium at 4°C and room temperature. Analysis of steady state binding data by the method of Scatchard and by unlabeled ProTα competition experiments identified two binding sites with an apparent equilibrium dissociation constant of 216–321 pM for the high-affinity receptor and of 11.4–21.1 nM for the low-affinity one; the sites per cell ranged from 1,479 to 1,519 and from 47,547 to 56,169, respectively. The kinetically derived equilibrium dissociation constant agreed with these data and showed no interaction between receptors

    Synthesis of bench-stable solid triorganoindium reagents and reactivity in palladium-catalyzed cross-coupling reactions

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    [Abstract] Bench-stable solid triorganoindium compounds have been prepared by coordination with 4-(dimethylamino)pyridine (DMAP). The solid R3In(DMAP) complexes are obtained from the corresponding solution of R3In in quantitative yield and can be stored for up to several weeks. These reagents show excellent reactivity in palladium-catalyzed cross-coupling reactions with organic electrophiles.Ministerio de Economía y Competitividad; CTQ2015-68369-PGalicia. Consellería de Cultura, Educación e Ordenación Universitaria; GRC2014/04

    Transition-metal-free cross-coupling of indium organometallics with chromene and isochroman acetals mediated by BF3·OEt2

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    [Abstract] A transition-metal-free coupling of triorganoindium reagents with benzopyranyl acetals mediated by a Lewis acid has been developed. The reaction of R3In with chromene and isochroman acetals in the presence of BF3·OEt2 afforded 2-substituted chromenes and 1-substituted isochromans, respectively, in good yields. The reactions proceed with a variety of triorganoindium reagents (aryl, heteroaryl, alkynyl, alkenyl, alkyl) using only 50 mol % of the organometallic, thus demonstrating the efficiency of these species. Preliminary mechanistic studies indicate the formation of an oxocarbenium ion intermediate in the presence of the Lewis acid.Ministerio de Economía y Competitividad; CTQ2012-31200Ministerio de Economía y Competitividad; CTQ2015-68369-

    Triorganoindium reagents in Rh-catalyzed C–H activation/C–C cross-coupling reactions of 2-arylpyridines

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    [Abstract] The activation of C–H bonds through catalytic reactions using transition metals is an important challenge in organic chemistry in which the intermediates are related to those produced in the classical cross-coupling reactions. As part of our research program devoted to the development of metal-catalyzed reactions using indium organometallics, a protocol for the C–H activation and C–C coupling of 2-arylpyridines with triorganoindium reagents under Rh(I) catalysis is reported. Under the optimized conditions, we found that Me3In and Ar3In reagents reacted with 2-arylpyridines and related compounds in the presence of Rh(PPh3)3Cl, in PhCl/THF (9:1), at 120 °C for 48 h, to afford the ortho-coupling products in moderate to good yields. The nitrogen atom in the pyridine ring acts as a directing group to assist the functionalization at the ortho position of the aryl group forming a new C–C bond at this position.Ministerio de Economía y Competitividad; CTQ2015-68369-PXunta de Galicia; GRC2014/04

    Sequential In-catalyzed intramolecular hydroarylation and Pd-catalyzed cross-coupling reactions using bromopropargyl aryl ethers and amines

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    [Abstract] A sequential one-pot indium-catalyzed intramolecular hydroarylation (IMHA) of bromopropargyl aryl ethers and amines, and palladium-catalyzed cross-coupling reaction using triorganoindium reagents (R3In) has been developed. In this transformation, the IMHA of 3-bromo-2-propynyl aryl ethers under indium(III) catalysis, proceeds regioselectively through a 6-endo dig pathway to afford 4-bromo-2Hchromenes. Subsequent palladium-catalyzed cross-coupling with R3In gives 4-substituted-2H-chromenes in one-pot. This sequential transformation was extended to 3-bromo-2-propynyl-N-tosylanilines to afford 4-substituted-1,2-dihydroquinolines. The dual-catalyzed procedure takes place efficiently with a variety of propargyl aryl ethers and amines and R3In (R = aryl, heteroaryl, alkyl or alkynyl), showing the efficiency of these organometallics and proving the compatibility of indium and palladium in catalysis.Ministerio de Economía y Competividad; CTQ2015-68369-PXunta de Galicia. Consellería de Cultura, Educación e Ordenación Universitaria; GRC2014/04

    Indium(III)-Catalyzed Stereoselective Synthesis of Tricyclic Frameworks by Cascade Cycloisomerization Reactions of Aryl 1,5-Enynes

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    Financiado para publicación en acceso aberto: Universidade da Coruña/CISUGThe Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acs.joc.1c00825 (https://pubs.acs.org/doi/suppl/10.1021/acs.joc.1c00825/suppl_file/jo1c00825_si_001.pdf)[Abstract] The indium(III)-catalyzed cascade cycloisomerization reaction of 1,5-enynes with pendant aryl nucleophiles is reported. The reaction proceeds in cascade under mild reaction conditions, using InI₃ (5 mol %) as a catalyst with a range of 1,5-enynes furnished with aryl groups (phenyl and phenol) at alkene (E and Z isomers) and with terminal and internal alkynes. Using 1-bromo-1,5-enynes, a one-pot sequential indium-catalyzed cycloisomerization and palladium-catalyzed cross-coupling with triorganoindium reagents were developed. The double cyclization is stereospecific and operates via a biomimetic cascade cation-olefin through 1,5-enyne cyclization (6-endo-dig) and subsequent C–C hydroarylation or C–O phenoxycyclization. Density functional theory (DFT) computational studies on 1,5-enynyl aryl ethers support a two-step mechanism where the first stereoselective 1,5-enyne cyclization produces a nonclassical carbocation intermediate that evolves to the tricyclic reaction product through a SᴇAr mechanism. Using this approach, a variety of tricyclic heterocycles such as benzo[b]chromenes, phenanthridines, xanthenes, and spiroheterocyclic compounds are efficiently synthesized with high atom economy.We thank the Spanish Ministerio de Ciencia, Innovación y Universidades (PGC2018-097792-B-I00 and PID 2019-110008GB-I00), Xunta de Galicia (GRC2018/039), IZO-SGI SGIker of UPV/EHU, and EDRF funds for financial and human supportXunta de Galicia; GRC2018/039https://pubs.acs.org/doi/suppl/10.1021/acs.joc.1c00825/suppl_file/jo1c00825_si_001.pd

    Synthesis and Structural Analysis of Push-Pull Imidazole-Triazole Based Fluorescent Bifunctional Chemosensor for CU2+ and FE2+ Detection

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    [Abstract] Fluorescent imidazole-triazole based ligands L1 and L2 have been designed as chemical push-pull chemosensors for divalent metal ions and synthesized through palladium-catalyzed cross-coupling reactions using indium organometallics and click chemistry. The novel ligands exhibit intense absorption in the ultraviolet region with high molar extinction coefficients, and strong fluorescence emission with large Stokes displacements. On the basis of UV–Vis absorption spectroscopy and fluorescence emission data in acetonitrile, L1 is shown as a bifuncional chemosensor with differential response for Fe2+ and Cu2+ over a range of selected 3d divalent and other metal ions. The binding site of the ligand was established by single-crystal X-ray diffraction and 1H NMR spectroscopy studies. The association constants, determined by spectrofluorimetric titrations, show a steady binding affinity of L1 for Cu2+ and Fe2+ in comparison with other previously reported fluorescent bidentate chemosensors, offering the lowest limit of detection (LOD) with Cu2+. DFT calculations provide a rationale properly understanding and interpreting the experimentally observed results. Indeed, a mechanism of the different optical responses of L1 towards 3d divalent metal ions is proposed.We thank the Spanish Ministerio de Ciencia, Innovación y Universidades (PGC2018-097792-B-I00), Xunta de Galicia (GRC2018/039 and ED431B 2020/52) and EDRF funds for financial and human support. ADL thanks the Xunta de Galicia for a predoctoral fellowship (EDA 481A-2020/017). LV thanks CACTI for X-ray measurementsXunta de Galicia; GRC2018/039Xunta de Galicia; ED431B 2020/52Xunta de Galicia; ED 481A-2020/01

    Allergic Rhinitis Improvement After Septorhinoplasty in a Sample of Allergic Rhinitis Patients With Septal Deviation: A Quasi-Experimental Study

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    [Abstract] BACKGROUND: Allergic rhinitis (AR) is a chronic inflammatory disease that affects almost 30% of the adult population. OBJECTIVE: To describe and compare the evolution of symptoms in patients diagnosed with AR and septal deviation prior to and following septoplasty (STP). DESIGN AND SETTING: Quasi-experimental study developed in A Coruña University Hospital. METHODS: Patients aged 18-65 years who had been diagnosed with AR and septal deviation were recruited. Obstruction airflow was evaluated before and after surgery, by means of anterior rhinomanometry (RNM). Severity symptoms and quality of life were assessed using a visual analogue scale (VAS) and the ESPRINT questionnaire, respectively. RESULTS: A total of 50 subjects underwent STP and 42 were included in this study. Their mean age at the time of surgery was 34.16 ± 9.74 years (range 18-64). Significant reductions in mean VAS and ESPRINT were observed after surgery (P < 0.01). These outcomes were considered to represent an overall improvement in quality of life. The RNM results also improved significantly, from mean values of 478.07 ± 165.4 cm3/s before STP to 826.4 ± 175.5 cm3/s afterwards (P < 0.01). CONCLUSIONS: The negative correlations of VAS and ESPRINT with RNM, from before and to after STP, demonstrate the efficacy of scales and questionnaires as objective methods for determining obstruction in the absence of rhinomanometry. Patients with allergic rhinitis and septal deviation showed improvements in obstruction severity and medication use after STP. OBJECTIVE: To describe and compare the evolution of symptoms in patients diagnosed with AR and septal deviation prior to and following septoplasty (STP). DESIGN AND SETTING: Quasi-experimental study developed in A Coruña University Hospital. METHODS: Patients aged 18-65 years who had been diagnosed with AR and septal deviation were recruited. Obstruction airflow was evaluated before and after surgery, by means of anterior rhinomanometry (RNM). Severity symptoms and quality of life were assessed using a visual analogue scale (VAS) and the ESPRINT questionnaire, respectively. RESULTS: A total of 50 subjects underwent STP and 42 were included in this study. Their mean age at the time of surgery was 34.16 ± 9.74 years (range 18-64). Significant reductions in mean VAS and ESPRINT were observed after surgery (P < 0.01). These outcomes were considered to represent an overall improvement in quality of life. The RNM results also improved significantly, from mean values of 478.07 ± 165.4 cm3/s before STP to 826.4 ± 175.5 cm3/s afterwards (P < 0.01). CONCLUSIONS: The negative correlations of VAS and ESPRINT with RNM, from before and to after STP, demonstrate the efficacy of scales and questionnaires as objective methods for determining obstruction in the absence of rhinomanometry. Patients with allergic rhinitis and septal deviation showed improvements in obstruction severity and medication use after STP
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