Search results for "fluor"

Insight into mechanisms of creatinine optical sensing using fluorescein-gold complex

2022

Abstract Creatinine level in biological fluids is a clinically relevant parameter to monitor vital functions and it is well assessed that measuring creatinine levels in the human body can be of great utility to evaluate renal, muscular, or thyroid dysfunctions. The accurate detection of creatinine levels may have a critical role in providing information on health status and represents a tool for the early diagnosis of severe pathologies. Among different methods for creatinine detection that have been introduced and that are evolving with increasing speed, fluorescence-based and colorimetric sensors represent one of the best alternatives, thanks to their affordability, sensitivity and easy r…

Fluorine-containing functionalized cyclopentene scaffolds through ring contraction and deoxofluorination of various substituted cyclohexenes

2018

The fluorination of some highly‐functionalized cyclopentene derivatives, obtained from various substituted cyclohexenes through a ring‐opening/ring‐contraction procedure, has been investigated. The transformations were found to be highly substrate dependent, and led to the formation of various functionalized alicyclic compounds or heterocycles containing allyl difluoride or vinyl fluoride moieties. peerReviewed

Design, Synthesis and Evaluation of Fluorescent Analogues of Abscisic Acid

2020

A fluorescent analogue of abscisic acid has been prepared by combining (S)‐abscisic acid (ABA) with nitrobenzoxadiazole (NBD) fluorophore using ethanol amine as a linker. Isomerization of the double bond at the side chain of abscisic acid happened during the synthesis. The resulting fluorophore analogues derived from both isomeric compounds entered cells suggesting a wide applicability of the ABA‐NBD conjugates as fluorescent probes to study ABA mechanism of action. The functional properties of the isomeric ABA‐NBD conjugates were tested in vitro, by measuring TNFα expression and nitrite concentration in LPS‐stimulated macrophages and compared with their non‐fluorescent ABA isomers. Rationa…

Optimization of the JUNO liquid scintillator composition using a Daya Bay antineutrino detector

2021

To maximize the light yield of the liquid scintillator (LS) for the Jiangmen Underground Neutrino Observatory (JUNO), a 20 t LS sample was produced in a pilot plant at Daya Bay. The optical properties of the new LS in various compositions were studied by replacing the gadolinium-loaded LS in one antineutrino detector. The concentrations of the fluor, PPO, and the wavelength shifter, bis-MSB, were increased in 12 steps from 0.5 g/L and <0.01 mg/L to 4 g/L and 13 mg/L, respectively. The numbers of total detected photoelectrons suggest that, with the optically purified solvent, the bis-MSB concentration does not need to be more than 4 mg/L. To bridge the one order of magnitude in the detect…

Difensulfonu un benzofenonu atvasinājumu optiskie pētījumi 3. paaudzes organiskām gaismu emitējošām diodēm

2021

Darbā tika pētīti TADF difenilsulfonu un benzofenonu atvasinājumi ar karbazola grupām ar mērķi atrast potenciālu zilās gaismas emiteri. TADF efekta pierādīšanai tika izmantoti degazēti un nedegazēti šķīdinātāji, jo skābeklis mijiedarbojas ar ierosinātajiem tripleta stāvokļiem un būtiski samazina savienojumu emisijas. No dotajiem savienojumiem tika izveidoti OLED. Visefektīvākajiem savienojumiem tika veidotas viesu-saimnieka sistēmas ar mērķi uzlabot emisijas spējas. Par matricu tika izvēlēti divu veidu karbazolu atvasinājumi ar salīdzinoši augstiem tripletu līmeņiem. No sistēmām tikai izveidoti OLED, izmērītas to elektriskās un emisijas īpašības. Labākā zaļganās nokrāsas organiskās gaismas …

One-pot cross-enyne metathesis (CEYM)-Diels-Alder reaction of gem-difluoropropargylic alkynes.

2013

Propargylic difluorides 1 were used as starting substrates in a combination of cross-enyne metathesis and Diels–Alder reactions. Thus, the reaction of 1 with ethylene in the presence of 2nd generation Hoveyda–Grubbs catalyst generates a diene moiety which in situ reacts with a wide variety of dienophiles giving rise to a small family of new fluorinated carbo- and heterocyclic derivatives in moderate to good yields. This is a complementary protocol to the one previously described by our research group, which involved the use of 1,7-octadiene as an internal source of ethylene.

Novel Stereoselective Intramolecular Processes for the Generation of New Molecular Entities

2019

La Química Orgánica, además de constituir una fuente inagotable de fascinación académica por su capacidad de generar un número virtualmente infinito de nuevas estructuras moleculares, ha proporcionado una poderosa herramienta, el cribado de librerías de moléculas orgánicas, en el ámbito de la química biológica/médica y el descubrimiento de fármacos que se ha convertido en el caballo de batalla en la identificación de nuevas dianas terapéuticas y sus correspondientes moduladores y potenciales fármacos, con un impacto directo sobre la salud humana. La principal problemática de estas librerías es el aspecto de la diversidad estructural, ya que la probabilidad de dar con un fármaco candidato es…

Nanopiattaforme di Ossido di Grafene perfluorurate: materiali biocompatibili con affinità per l'ossigeno

L’attacco covalente di molecule perfluorurate su ossido di graphene (GO) via sostituzione nucleofila aromatica ha consentito una facile funzionalizzazione delle lamelle di GO.1,2 La performance delle nanopiattaforme perluorurate (GOF) nell’uptake e rilascio di ossigeno è stata valutata in condizioni di pH fisiologico a differenti concentrazioni e temperature, dimostrando una maggiore affinità del materiale perfluorurato GOF rispetto al GO pristino. Anche a basse concentrazioni GOF ha mostrato valori di uptake di ossigeno a saturazione e velocità di diffusione superiori ad altri materiali proposti in letteratura per ingegneria tissutale, per l’ossigenazione cellulare durante la rigenerazione…

1,1prime-Binaphthyl-2-methylpyridinium-based peroxophosphotungstate salts: synthesis, characterization, and their use as oxidation catalysts

2009

A series of 1,1′-binaphthyl-2-methylammonium and pyridinium salts 6, 7, and 8 was synthesized through the coupling reaction of 2-(bromomethyl)-1,1′-binaphthalene (5) with the dendritic tetraallyl pyridinedicarbinol dendron 2 as well as triethylamine and 4-tert-butylpyridine. Tetraallyl pyridinedicarbinol dendron 2 was prepared by allylation of commercially available diethyl pyridine-3,5-dicarboxylate (1). The allylation of 2 with allyltrimethylsilane in the presence of boron trifluoride was unsuccessful, as tetraallyl pyridinedicarbinol trifluoroboron adduct 3 was obtained instead of expected hexaallylpyridine compound 4. The catalytic hydrogenation of allyl groups of the ammonium salt of 2…

Increased dosage of Ink4/Arf protects against glucose intolerance and insulin resistance associated with aging

2013

Recent genome-wide association studies have linked type-2 diabetes mellitus to a genomic region in chromosome 9p21 near the Ink4/Arf locus, which encodes tumor suppressors that are up-regulated in a variety of mammalian organs during aging. However, it is unclear whether the susceptibility to type-2 diabetes is associated with altered expression of the Ink4/Arf locus. In the present study, we investigated the role of Ink4/Arf in age-dependent alterations of insulin and glucose homeostasis using Super-Ink4/Arf mice which bear an extra copy of the entire Ink4/Arf locus. We find that, in contrast to age-matched wild-type controls, Super-Ink4/Arf mice do not develop glucose intolerance with agi…