Results 111 to 120 of about 5,000,063 (295)
Are Strong Bronsted Acids Necessarily Strong Lewis Acids? [PDF]
arXiv, 2006 The Broensted and Lowry acid base theory is based on the capacity of proton donation or acceptance (in the presence or absence of a solvent) whereas the Lewis acid base theory is based on the propensity of electron pair acceptance or donation. We explore through DFT calculation the obvious question whether these two theories are in conformity with each
arxiv
A search for mid-IR bands of amino acids in the Perseus Molecular Cloud [PDF]
arXiv, 2021 Amino acids are building-blocks of proteins, basic constituents of all organisms and essential to life on Earth. They are present in carbonaceous chondrite meteorites and comets, but their origin is still unknown. Formation of amino acids in the interstellar medium is posible via specific gas-phase reactions in dark clouds, however sensitive ...
arxiv
Functionalized periodic mesoporous organosilicas : from metal free catalysis to sensing
, 2019 In this work a widely usable post-modification route for periodic mesoporous organosilicas (PMOs) was developed. Using the developed method, two diverse ligands, picolinic acid (Pic) and 4,4 ',4 '',4 '''-porphyrin-5,10,15,20-tetrayltetrabenzoic acid ...
Bourda, Laurens +4 more
core +2 more sources
The kynurenine pathway and the brain: challenges, controversies and promises [PDF]
, 2017 Research on the neurobiology of the kynurenine pathway has suffered years of relative obscurity because tryptophan degradation, and its involvement in both physiology and major brain diseases, was viewed almost exclusively through the lens of the well ...
Schwarcz, Robert, Stone, Trevor W.
core +1 more source
Oxidation‐Deformylation Cascade Catalyzed By a Mononuclear Copper Complex
Chemistry – A European Journal, Volume 31, Issue 26, May 8, 2025.A bioinspired copper complex is able to catalyze two successive oxidative steps of alcohol conversion in the presence of hydrogen peroxide under mild conditions: (i) alcohol oxidation to aldehyde and (ii) aldehyde deformylation. Isotopic effects on the reaction rates indicate that hydrogen atom abstraction is rate limiting for both steps.
Yongxing Wang +8 more
wiley +1 more source
The Factors of the Classification of Protein Amino Acids [PDF]
This paper is published in GLASNIK of Montenegrin Academy of
Science and arts, 2000, 13, pp. 173-194, 2006 In this work it is shown that three pairs of the factors appear to be the key, i.e. main factors of a natural classification of protein (canonical) amino acids within the amino acid (genetic) code. First pair: the factors of the habit of an amino acid molecule (size and polarity).
arxiv
E-Journal of Chemistry, 2005 The reaction of Co(NO3)2.6H2O and Ni(NO3)2.6H2O with hydrazones derived from 1-phenyl-3-methyl-4-acyl-5-pyrazolone (where acyl = acetyl, propionyl, butyryl and benzoyl) with 2-picolinic acid hydrazide have been studied and characterized on the basis of ...
Chetan K. Modi +2 more
doaj +1 more source
Preparation of (S)-tert-ButylPyOx and Palladium-Catalyzed Asymmetric Conjugate Addition of Arylboronic Acids [PDF]
, 2015 A. (S)-N-(1-Hydroxy-3,3-dimethylbutan-2-yl)picolinamide (2). A 1 L one-necked round-bottomed flask equipped with a 3.0 cm x 1.4 cm, egg-shaped, Teflon-coated magnetic stirring bar is sealed with a septum and connected via needle adapter to a two-tap ...
Holder, Jeffrey C. +4 more
core +1 more source
Kynurenine pathway metabolite alterations in Down syndrome and Alzheimer's disease
Alzheimer's &Dementia, Volume 21, Issue 5, May 2025.Abstract INTRODUCTION Down syndrome (DS) is a genetic disorder that leads to intellectual disability and accelerated aging, increasing the risk of Alzheimer's disease (AD). The pathophysiology of AD and DS is multifactorial, involving amyloid precursor protein overexpression, neuroinflammation, and oxidative stress.
Rafaela Gomes dos Reis +4 more
wiley +1 more source