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1.
Chemistry ; 30(23): e202400516, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38348814

RESUMEN

The field of bioorthogonal chemistry is rapidly growing, presenting successful applications of organic and transition metal-catalysed reactions in cells and living systems (in vivo). The development of such reactions typically proceeds through many iterative steps focused on biocompatibility and fast reaction kinetics to ensure product formation. However, obtaining kinetic data, even under simulated biological (biomimetic) conditions, remains a challenge due to substantial concentrations of salts and biomolecules hampering the use of typically employed solution-phase analytical techniques. In this study, we explored the suitability of gas evolution as a probe to study kinetics under biomimetic conditions. As proof of concept, we show that the progress of two transition metal-catalysed bioorthogonal chemical reactions can be accurately monitored, regardless of the complexity of the medium. As such, we introduce a protocol to gain more insight into the performance of a catalytic system under biomimetic conditions to further progress iterative catalyst development for in vivo applications.


Asunto(s)
Biomimética , Catálisis , Cinética , Biomimética/métodos , Gases/química , Elementos de Transición/química , Materiales Biomiméticos/química
2.
Molecules ; 28(17)2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37687024

RESUMEN

Since Hydrogen Sulfide (H2S) was recognized as a gas transmitter, its detection and quantification have become a hot research topic among chemists and biologists. In this area, fluorescent probes have shown great advantages: fast and strong response, low detection limit and easy manipulation. Here we developed a new fluorescent probe that detected H2S selectively among various bioactive and inorganic salts. This probe was based on the core structure of fluorescein and reacted with H2S through azide-reduction. Great linearity was achieved correlating fluorescence intensity and H2S concentrations in solution. The detection of H2S in cancer cells was also achieved.


Asunto(s)
Colorantes Fluorescentes , Sulfuro de Hidrógeno , Fluoresceína , Azidas , Concentración de Iones de Hidrógeno
3.
Molecules ; 28(3)2023 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-36770961

RESUMEN

Hydrogen sulfide (H2S) is an essential signaling gas within the cell, and its endogenous levels are correlated with various health diseases such as Alzheimer's disease, diabetes, Down's syndrome, and cardiovascular disease. Because it plays such diverse biological functions, being able to detect H2S quickly and accurately in vivo is an area of heightened scientific interest. Using probes that fluoresce in the near-infrared (NIR) region is an effective and convenient method of detecting H2S. This approach allows for compounds of high sensitivity and selectivity to be developed while minimizing cytotoxicity. Herein, we report a review on the synthesis, mechanisms, optical properties, and selected biomedical applications of H2S sensors.


Asunto(s)
Colorantes Fluorescentes , Sulfuro de Hidrógeno , Transducción de Señal
4.
Molecules ; 27(16)2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-36014540

RESUMEN

Nitroxyl shows a unique biological profile compared to the gasotransmitters nitric oxide and hydrogen sulfide. Nitroxyl reacts with thiols as an electrophile, and this redox chemistry mediates much of its biological chemistry. This reactivity necessitates the use of donors to study nitroxyl's chemistry and biology. The preparation and evaluation of a small library of new redox-triggered nitroxyl sources is described. The condensation of sulfonyl chlorides and properly substituted O-benzyl hydroxylamines produced O-benzyl-substituted sulfohydroxamic acid derivatives with a 27-79% yield and with good purity. These compounds were designed to produce nitroxyl through a 1, 6 elimination upon oxidation or reduction via a Piloty's acid derivative. Gas chromatographic headspace analysis of nitrous oxide, the dimerization and dehydration product of nitroxyl, provides evidence for nitroxyl formation. The reduction of derivatives containing nitro and azide groups generated nitrous oxide with a 25-92% yield, providing evidence of nitroxyl formation. The oxidation of a boronate-containing derivative produced nitrous oxide with a 23% yield. These results support the proposed mechanism of nitroxyl formation upon reduction/oxidation via a 1, 6 elimination and Piloty's acid. These compounds hold promise as tools for understanding nitroxyl's role in redox biology.


Asunto(s)
Sulfuro de Hidrógeno , Óxido Nitroso , Sulfuro de Hidrógeno/química , Óxido Nítrico , Óxidos de Nitrógeno/química , Oxidación-Reducción
5.
J Labelled Comp Radiopharm ; 61(12): 895-902, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30101475

RESUMEN

Radiolabelled azidophenyl analogues can make powerful photoaffinity probes for the identification of molecular targets. We describe our efforts to prepare tritiated azidophenyl analogues of the taxols cabazitaxel and docetaxel. Late-stage tritiation by isotope exchange with diiodo precursors resulted in reduction of the azide moiety, which could only be overcome by addition of high excess of a sacrificial azide. Iodine-deuterium exchange experiments on a model system established that deiodination with concomitant azide reduction is a general problem when performing such isotope-exchange reactions on azide-containing aryl iodides.


Asunto(s)
Azidas/química , Docetaxel/química , Yodo/química , Etiquetas de Fotoafinidad/química , Taxoides/química , Tritio/química , Marcaje Isotópico , Modelos Moleculares , Conformación Molecular
6.
Tetrahedron Lett ; 55(40): 5566-5569, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25221360

RESUMEN

Hydrogen sulfide (H2S) has been recently recognized as an important signaling molecule in biological systems. Herein, we report the development of a fluorescence turn-on probe based on the structure of pomalidomide, a FDA approved drug for the treatment of multiple myeloma. Various characterizations demonstrated high selectivity and sensitivity of this probe towards H2S. Furthermore, the application of this probe to detect H2S in living cells was confirmed by flow cytometry and fluorescence imaging studies.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117690, 2020 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-31740124

RESUMEN

Design and synthesis of fluorescent probe with fast response, excellent water solubility and good hepatocyte-targeting capacity to detect hydrogen sulfide (H2S) in hepatocytes and water samples is of great significance. Here, a novel fluorescent probe QL-Gal-N3 for detection of H2S was designed and synthesized based on H2S-mediated azide reduction strategy. This sensor demonstrated low toxicity, fast response (within 1 min), high selectivity and low detection limit (as low as 126 nM in water) for the detection of H2S. HeLa, A549 and HepG-2 cells were chosen to investigate the hepatocyte-targeting ability of QL-Gal-N3 respectively. The results indicated that the specific recognition of ASGPR over-expressed in hepatocytes by galactose group was an important reason for the good targeting ability of probe QL-Gal-N3. Furthermore, due to the introduction of glycosyl moiety, the water solubility of fluorescent probe was enhanced obviously. It was successfully applied for the detection of H2S in environmental water samples including river water, tap water, lake water and waste water.


Asunto(s)
Colorantes Fluorescentes/síntesis química , Hepatocitos/metabolismo , Sulfuro de Hidrógeno/análisis , Agua/química , Células A549 , Células HeLa , Células Hep G2 , Humanos , Concentración de Iones de Hidrógeno , Lagos/química , Microscopía Fluorescente , Ríos/química , Factores de Tiempo , Aguas Residuales/química
8.
Carbohydr Res ; 489: 107948, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32062397

RESUMEN

Rh/Al2O3 can be used as an effective chemo-selective reductive catalyst that combines the mild conditions of catalytic hydrogenation with high selectivity for azide moieties in the presence of other hydrogenolysis labile groups such as benzyl and benzyloxycarbonyl functionalities. The practicality of this strategy is exemplified with a range of azide-containing carbohydrate and amino acid derivatives.


Asunto(s)
Aminas/síntesis química , Azidas/química , Rodio/química , Aminas/química , Conformación de Carbohidratos , Catálisis , Hidrogenación
9.
Anal Chim Acta ; 896: 160-5, 2015 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-26482000

RESUMEN

A series of lanthanide-based, azide-appended complexes were investigated as hydrogen sulfide-sensitive probes. Europium complex 1 and Tb complex 3 both displayed a sulfide-dependent increase in luminescence, while Tb complex 2 displayed a decrease in luminescence upon exposure to NaHS. The utility of the complexes for monitoring sulfide levels in industrial oil and water samples was investigated. Complex 3 provided a sensitive measure of sulfide levels in petrochemical water samples (detection limit âˆ¼ 250 nM), while complex 1 was capable of monitoring µM levels of sulfide in partially refined crude oil.


Asunto(s)
Residuos Industriales/análisis , Elementos de la Serie de los Lantanoides/química , Sustancias Luminiscentes/química , Compuestos Organometálicos/química , Sulfuros/análisis , Mediciones Luminiscentes , Estructura Molecular
10.
Methods Enzymol ; 554: 63-80, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25725516

RESUMEN

Hydrogen sulfide is a redox active sulfur species that is endogenously generated in mammalian systems as an antioxidant and signaling molecule to support cellular function. The fundamental and ubiquitous actions of hydrogen sulfide demand sensitive and specific methods to track this biomolecule as it is produced within living organisms with temporal and spatial regulation. In this context, the hydrogen sulfide-mediated reduction of an azide to an amine is a useful method for organic synthesis, and this reaction has successfully been exploited to yield biocompatible fluorescent probes for hydrogen sulfide detection in vitro and in cells. This chapter provides protocols and guidelines for applying azide-based fluorescence probes to detecting hydrogen sulfide in living systems, including a protocol that was used to detect endogenous hydrogen sulfide in living single cells using a confocal microscope.


Asunto(s)
Azidas/química , Colorantes Fluorescentes/química , Sulfuro de Hidrógeno/química , Técnicas de Cultivo de Célula , Células Cultivadas , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Sulfuro de Hidrógeno/metabolismo , Microscopía Fluorescente , Coloración y Etiquetado , Factor A de Crecimiento Endotelial Vascular/metabolismo
11.
Bioresour Technol ; 169: 265-270, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25062537

RESUMEN

The effects of azide on electron transport of exoelectrogens were investigated using air-cathode MFCs. These MFCs enriched with azide at the concentration higher than 0.5mM generated lower current and coulomb efficiency (CE) than the control reactors, but at the concentration lower than 0.2mM MFCs generated higher current and CE. Power density curves showed overshoot at higher azide concentrations, with power and current density decreasing simultaneously. Electrochemical impedance spectroscopy (EIS) showed that azide at high concentration increased the charge transfer resistance. These analyses might reflect that a part of electrons were consumed by the anode microbial population rather than transferred to the anode. Bacterial population analyses showed azide-enriched anodes were dominated by Deltaproteobacteria compared with the controls. Based on these results it is hypothesized that azide can eliminate the growth of aerobic respiratory bacteria, and at the same time is used as an electron acceptor/sink.


Asunto(s)
Aire , Azidas/toxicidad , Fuentes de Energía Bioeléctrica , Electrones , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Reactores Biológicos/microbiología , Técnicas Electroquímicas , Electrodos , Transporte de Electrón/efectos de los fármacos , Oxígeno/análisis , Factores de Tiempo
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