Search results for "Dative"

Genotoxic and endocrine activities of bis(hydroxyphenyl)methane (bisphenol F) and its derivatives in the HepG2 cell line

2008

International audience; Human can be exposed to bis(hydroxyphenyl)methane (bisphenol F or BPF) and its derivatives as environment and food's contaminants. This study was investigated to identify and to compare toxic potency of BPF, BFDGE, and two of BPF metabolites using in vitro methods. BPF did not induce any genic mutation in bacteria when the Ames test was performed according to the OECD guideline. In contrast, using Human cell lines and Comet assay, we demonstrated that BPF and Bisphenol F Diglycidyl Ether (BFDGE) were effective on HepG2 cell DNA fragmentation at non-cytotoxic concentrations. DHB was also positive but at higher concentrations, near its limit of solubility. Neither BPF,…

Unique regioselectivity in the C(sp3)-H α-alkylation of amines: the benzoxazole moiety as a removable directing group.

2014

The benzoxazol-2-yl- substituent was found to act as a removable activating and directing group in the Ir-catalyzed alkylation of C(sp(3))-H bonds adjacent to nitrogen in secondary amines. It can be easily introduced by oxidative coupling or by an SNAr reaction, and it can be removed by hydroxide or by hydride reduction. For 1,2,3,4-tetrahydroisoquinolines, activation exclusively takes place in the 3-position. A variety of activated as well as unactivated terminal olefins are suitable reaction partners.

(2,2‐Dibromovinyl)ferrocene as a Building Block for the Assembly of Heterodinuclear Complexes – Preparation of an σ‐Alkenylpalladium Complex and Dime…

2007

The oxidative addition of (2,2-dibromovinyl)ferrocene [Br2C=C(H)–Fc] (1) to [Pd(PPh3)4] yields the heterodinuclear σ-alkenyl complex trans-[{Pd(Br)(PPh3)2}–C(Br)=C(H)–Fc] (2). Nucleophilic attack of sodium thiolates on 1 unexpectedly affords the vinyl thioether derivatives (Z)-[(RS)(H)C=C(H)–Fc] (4a: R = Ph; 4b: R = tBu; 4c: R = Et). Complexes 4a and 4c can also be prepared by addition of NaSR across the triple bond of Fc–C≡C–H (3). Addition of an excess of NaSR to 1 affords the dithioether derivatives (Z)-[(RS)(H)C=C(SR)–Fc] (5a: R = Ph; 5b: R = p-tolyl; 5c: R = Et). An addition/elimination sequence is suggested to account for this surprising result. The yield of 5c is very low due to a co…

Stereocontrolled synthesis of five diastereomers of trimethyl 3-aminocyclopentane-1,2,4-tricarboxylates

2013

Abstract The sterically controlled oxidative cleavage of N - protected di exo - and di endo -substituted norbornene β-amino acids/esters resulted in four trimethyl 3-aminocyclopentane-1,2,4-carboxylate diastereomers. The sodium methoxide mediated isomerization of the four diastereomers in all cases yielded the thermodynamically most stable all- trans stereoisomer as a single product.

Palladium-Catalysed CH Bond Electrophilic Fluorination of Highly Substituted Arylpyrazoles: Experimental and DFT Mechanistic Insights

2015

A general protocol for palladium-catalysed CH mono- and di-fluorination of highly substituted arylpyrazoles is reported. Coupling pathways and substrate limitations are discussed in the light of complementary mechanistic experimental and density functional theory (DFT) studies. The mono- and di-ortho-fluorination of arylpyrazoles having substituted pyrazole groups and ortho-, meta-, or para-substituted arene moieties is achieved. Various pyrazole groups can efficiently promote the direct CH activation/fluorination of substrates bearing valuable reactive ester, cyano, halide and nitro functions. The presence of methoxy, methyl and trifluoromethyl is tolerated on the pyrazole directing groups…

Disulfide stress as a novel type of oxidative stress in acute inflammation

2012

SP404OXIDATIVE STRESS AND CHRONIC KIDNEY DISEASE: TRAVELLING COMPANIONS

2019

Role of beta3-adrenergic receptors in intestinal diseases

2022

The Inflammatory Bowel Diseases (IBD), characterized by a gastro-intestinal tract inflammation, are a global health-care problem due to their morbidity, mortality and the constant increase in their worldwide incidence. The available therapies are still not curative only providing temporary symptomatic relief and reduction in complications.Although etiology is still unclear, IBD results in an interplay of various factors among which impaired and/or inappropriate immune response toward intestinal bacteria. Increasing disease incidence link environmental triggers occurring during socioeconomic development to IBD, especially stress. In this work, we aimed to investigated the role of adrenergic …

Incidences de l’ischémie cérébrale sur la fonction et la sensibilité cardiaques à l’ischémie

2019

For years, the relationship between cardiac and neurological ischemic events has been limited to overlapping pathophysiological mechanisms and common risk factors. However, acute stroke may induce dramatic changes in cardiovascular function.The aim of this study was to evaluate how prior cerebrovascular lesions affect myocardial function and signaling in vivo and ex vivo, and how they influence cardiac vulnerability to ischemia-reperfusion injury and the expression of cardiac genes and proteins involved in cardioprotective pathways.Thus, in our work, we studied cardiac function in a rat stroke model induced by cerebral embolization.The main results show that experimental stroke 1/ impaired …

Antineoplastic Drug-Induced Cardiotoxicity: A Redox Perspective

2018

Antineoplastic drugs can be associated with several side effects, including cardiovascular toxicity (CTX). Biochemical studies have identified multiple mechanisms of CTX. Chemoterapeutic agents can alter redox homeostasis by increasing the production of reactive oxygen species (ROS) and reactive nitrogen species RNS. Cellular sources of ROS/RNS are cardiomyocytes, endothelial cells, stromal and inflammatory cells in the heart. Mitochondria, peroxisomes and other subcellular components are central hubs that control redox homeostasis. Mitochondria are central targets for antineoplastic drug-induced CTX. Understanding the mechanisms of CTX is fundamental for effective cardioprotection, without…