Search results for "acetaldehyde"

Efficient Synthesis of 1,4,7-Triazacyclononane and 1,4,7-Triazacyclononane-Based Bifunctional Chelators for Bioconjugation

2014

The reaction of diethylenetriamine with chloroacetaldehyde yielded a bicyclic aminal intermediate for the synthesis of 1,4,7-triazacyclononane (TACN), a macrocyclic polyamine the derivatives of which find applications as catalysts, bleaching agents, and chelators for medical imaging. This new synthetic protocol outperforms the synthetic methods described so far because it does not involve any cyclization step. Moreover, this aminal intermediate allowed access to a new family of TACN derivatives functionalized on the carbon skeleton, for example, C-aminomethyl-TACN. This novel compound is a precursor of valuable bifunctional chelating agents for nuclear medicine, in particular, for the prepa…

SY26-4REVIEWING THE NEUROBIOLOGICAL EFFECTS OF SALSOLINOL: ROLE OF THE MU OPIOID RECEPTORS

2015

During the last decades Salsolinol (SAL), a condensation product from dopamine (DA) and acetaldehyde that appears in the brain of humans and rodents as a consequence of brain metabolism of ethanol, has been proposed as a key component in the development of alcohol use disorders. Although evidence has been published …

Über die zersetzung von hydroperoxyden durch katalase und durch lebereiweißfraktionen

1959

Es werden Herstellung und Eigenschaften einer Eiweisfraktion aus Rinderleber beschrieben, die auf Wasserstoffperoxyd, athyl-, Isopropyl- und tert.-Butylhydroperoxyd zersetzende Wirkung ausubt. Der fur das Zustandekommen der Zersetzungsreaktion der drei letzgenannten Peroxyde notwendige Acceptor wird als athanol identifiziert. Die Eiweisfraktion wird bezuglich ihrer Eigenschaften mit einer kristallisierten Katalase verglichen und aus dem Ergebnis der Schlus gezogen, das sie mit Katalase identisch ist. Als Reaktionsprodukt der enzymatisch katalysierten Reaktion zwischen tert.-Butylhydroperoxyd und athanol wurde Acetaldehyd nachgewiesen. The preparation and properties of an albumen fraction fr…

Synthesis of hyacinth, vanilla, and blossom orange fragrances: the benefit of using zeolites and delaminated zeolites as catalysts

2004

The synthesis of phenylacetaldehyde glycerol acetals, 2-benzyl-4-hydroxymethyl-1,3-dioxolane (1), 2-benzyl-5-hydroxy-1,3-dioxane (2), and vanillin propylene glycol acetal (2-(4-hydroxy-3-methoxyphenyl)-4-methyl-1,3-dioxolane) (3) which are flavoring compounds with hyacinth and vanilla scent fragrances, have been carried out successfully by acetalization of phenylacetaldehyde and vanillin with glycerol and propylene glycol, respectively, using toluene as solvent and zeolite catalysts whose adsorption properties have been optimized. However, in the case of a larger size acetal such as 2-acetonaphthone propylene glycol acetal (4) with blossom orange scent, geometrical constraints make the diff…

Einflu� von Medikamenten auf den Acetaldehydspiegel im Blut nach Alkoholzufuhr (enzymatische Bestimmung des Acetaldehyd)

1957

Mit einer enzymatischen und damit spezifischen Bestimmung des Acetaldehyd in Korperflussigkeiten konnte folgendes festgestellt werden. 1. Im Blutserum von Ratten konnte in der Mehrzahl der Falle keine Acetaldehydkonzentration bestimmt werden, im Einzelfall jedoch bis zu 0,09 mg- %. Die bisher in der Literatur angegebenen Normwerte hinsichtlich des Acetaldehydgehaltes, die aber mit relativ unspezifischen Methoden bestimmt worden waren, liesen sich an Ratten nicht bestatigen. 2. Die bisher mitgeteilten Konzentrationen an Acetaldehyd nach Verabreichung einer Sattigungsdosis von Antabus und Alkohol liegen uber 2 mg- %. Auch bei Uberprufung dieser Versuchsanordnung konnte niemals die Hohe dieser…

Acetaldehyde as a drug of abuse: Involvement of endocannabinoid- and dopamine neurotransmission

2014

Acetaldehyde (ACD), the first metabolite of ethanol, directly enhances dopamine neurotransmission (1) and has rewarding and motivational properties in paradigms tailored for studying addictive-like behaviours (2, 3). The endocannabinoid system affects distinct drug-related behaviours, since it may in turn fine-tune dopamine cell activity (4, 5). In light of this, the present study aimed at investigating the effects of a direct manipulation of the DAergic synapse, and the contribution of the endocannabinoid system on oral ACD self-administration in rats. ACD drinking-behaviour was evaluated in an operant paradigm consisting of acquisition and maintenance; extinction; deprivation and relapse;…

Oxidative Dehydrogenation of Ethanol on Gold : Combination of Kinetic Experiments and Computation Approach to Unravel the Reaction Mechanism

2021

Abstract Selective alcohol dehydrogenation on heterogeneous catalysts is a key industrial reaction for production of aldehydes, ketones, and carboxylic compounds. Design of catalysts with improved activity and selectivity requires understanding of the reaction mechanism and kinetics. Herein, experiments, density functional theory (DFT) and kinetic modelling were combined to elucidate the mechanism and kinetics of ethanol oxidative dehydrogenation to acetaldehyde on gold catalysts. Catalytic experiments clearly emphasized the role of oxygen in this reaction. Ethanol conversion was rather independent on the gold cluster size. Formation of minor products, acetic acid and ethyl acetate was stru…

Alcohol puts the heart under pressure: Acetaldehyde activates a localized renin angiotensin aldosterone system within the myocardium in alcoholic car…

2018

Effect of Acetaldehyde Intoxication and Withdrawal on NPY Expression: Focus on Endocannabinoidergic System Involvement

2014

Acetaldehyde (ACD), the first alcohol metabolite, plays a pivotal role in the rewarding, motivational and addictive properties of the parental compound. Many studies have investigated the role of ACD in mediating neurochemical and behavioral effects induced by alcohol administration, but very little is known about the modulation of neuropeptide systems following ACD intoxication and withdrawal. Indeed the neuropeptide Y (NPY) system is altered during alcohol withdrawal in key regions for cerebrocortical excitability and neuroplasticity. The primary goal of this research was to investigate the effects of ACD intoxication and withdrawal by recording rat behavior and by measuring neuropeptide …

Role of acetaldehyde in alcohol addiction: current evidence and future perspectives

2011

The effects of alcohol have been widely studied during the past century, corroborating the idea that this tiny chemical compound acts throughout most of our neurotransmitter systems since it is capable of inducing addictive behaviour. Two of the most serious problems of alcohol addiction are craving and relapse; several studies have demonstrated that relapse is related to the anxious state which occurs during withdrawal, and it has been proved that this behavioural modifications results from an alteration of the dopaminergic and serotonergic systems. An important role in the neurobiology of alcohol addiction is played by acetaldehyde (ACD), ethanol first metabolite. Our recent studies indee…