Slow glycosylation: Activation of trichloroacetimidates under mild conditions using lithium salts and the role of counterions

2022 ◽  
pp. 108497
Author(s):  
Nora Katharina Korber ◽  
Christian Marcus Pedersen
Keyword(s):  
Lithium Salts ◽  
Mild Conditions

Unprecedentedly high efficiency for photocatalytic conversion of methane to methanol over Au–Pd/TiO2 – what is the role of each component in the system?

2021 ◽  
Author(s):  
Xiaojiao Cai ◽  
Siyuan Fang ◽  
Yun Hang Hu
Keyword(s):  
Methane Conversion ◽  
High Efficiency ◽  
Mild Conditions ◽  
Highly Efficient ◽  
System P ◽  
Conversion Of Methane

Direct and highly efficient methane conversion to methanol under mild conditions is achieved via photocatalysis over Au–Pd/TiO2.

scholarly journals Design, synthesis, molecular docking, and in vitro α-glucosidase inhibitory activities of novel 3-amino-2,4-diarylbenzo[4,5]imidazo[1,2-a]pyrimidines against yeast and rat α-glucosidase

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Fariba Peytam ◽  
Ghazaleh Takalloobanafshi ◽  
Toktam Saadattalab ◽  
Maryam Norouzbahari ◽  
Zahra Emamgholipour ◽  
...  
Keyword(s):  
Molecular Docking ◽  
Docking Study ◽  
Rat Small Intestine ◽  
Molecular Docking Study ◽  
Design Synthesis ◽  
Mild Conditions ◽  
Glucosidase Inhibitors ◽  
Inhibitory Activities

AbstractIn an attempt to find novel, potent α-glucosidase inhibitors, a library of poly-substituted 3-amino-2,4-diarylbenzo[4,5]imidazo[1,2-a]pyrimidines 3a–ag have been synthesized through heating a mixture of 2-aminobenzimidazoles 1 and α-azidochalcone 2 under the mild conditions. This efficient, facile protocol has been resulted into the desirable compounds with a wide substrate scope in good to excellent yields. Afterwards, their inhibitory activities against yeast α-glucosidase enzyme were investigated. Showing IC50 values ranging from 16.4 ± 0.36 µM to 297.0 ± 1.2 µM confirmed their excellent potency to inhibit α-glucosidase which encouraged us to perform further studies on α-glucosidase enzymes obtained from rat as a mammal source. Among various synthesized 3-amino-2,4-diarylbenzo[4,5]imidazo[1,2-a]pyrimidines, compound 3k exhibited the highest potency against both Saccharomyces cerevisiae α-glucosidase (IC50 = 16.4 ± 0.36 μM) and rat small intestine α-glucosidase (IC50 = 45.0 ± 8.2 μM). Moreover, the role of amine moiety on the observed activity was studied through substituting with chlorine and hydrogen resulted into a considerable deterioration on the inhibitory activity. Kinetic study and molecular docking study have confirmed the in-vitro results.

scholarly journals Efficient alkene hydrosilation with bis(8-quinolyl)phosphine (NPN) nickel catalysts. The dominant role of silyl-over hydrido-nickel catalytic intermediates

2020 ◽  
Vol 11 (19) ◽  
pp. 5043-5051
Author(s):  
Jian Yang ◽  
Verònica Postils ◽  
Michael I. Lipschutz ◽  
Meg Fasulo ◽  
Christophe Raynaud ◽  
...  
Keyword(s):  
Nickel Complex ◽  
Dominant Role ◽  
Nickel Catalysts ◽  
Mild Conditions ◽  
Catalytic Intermediates

A cationic nickel complex of the bis(8-quinolyl)(3,5-di-tert-butylphenoxy)phosphine (NPN) ligand, [(NPN)NiCl]+, is a precursor to efficient catalysts for the hydrosilation of alkenes with hydrosilanes under mild conditions and low catalyst loadings.

Experimental and Theoretical Investigation of the Role of Bismuth in Promoting the Selective Oxidation of Glycerol over Supported Pt–Bi Catalyst under Mild Conditions

ACS Catalysis ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 6071-6083 ◽  
Author(s):  
Shixiang Feng ◽  
Jun Yi ◽  
Hiroki Miura ◽  
Naoki Nakatani ◽  
Masahiko Hada ◽  
...  
Keyword(s):  
Selective Oxidation ◽  
Theoretical Investigation ◽  
Mild Conditions

scholarly journals Studies on the protein-bound chondroitin sulphate of bovine cortical bone

1968 ◽  
Vol 107 (1) ◽  
pp. 41-49 ◽  
Author(s):  
G. M. Herring
Keyword(s):  
Ion Exchange ◽  
Cortical Bone ◽  
Chondroitin Sulphate ◽  
Bone Sialoprotein ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Mild Conditions ◽  
The Third ◽  
Apparent Homogeneity

A fraction containing chondroitin sulphate, isolated from bovine cortical bone under mild conditions, was separated by ion-exchange chromatography into three fractions with apparent homogeneity on electrophoresis and ultracentrifugation. Two of these appeared to consist of chondroitin sulphate bound to a glycoprotein ‘core’ that had similarities to the bone sialoprotein described previously. The differences in composition of the two fractions were considered to be due to variation in the number or lengths of the polysaccharide chains. The presence of xylose and the alkali-lability of the bond between protein and polysaccharide suggested the presence of a xylosylserine linkage. The third fraction had the properties of a relatively pure chondroitin sulphate which contained a small amount of peptide. These fractions differed considerably from the protein–polysaccharide complexes of epiphysial and other cartilages, and their relevance to the possible role of glycosaminoglycans is discussed.

scholarly journals Role of Aluminum and Lithium in Mitigating Alkali-Silica Reaction—A Review

2022 ◽  
Vol 8 ◽  
Author(s):  
Zhenguo Shi ◽  
Barbara Lothenbach
Keyword(s):  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Lithium Salts ◽  
Alkali Silica Reaction ◽  
Reaction Products ◽  
Ambient Conditions ◽  
Slow Kinetics ◽  
Zeolite Formation ◽  
Available Information

Effective mitigation of alkali-silica reaction (ASR) is critical for producing durable concrete. The use of alumina-rich supplementary cementitious materials (SCMs) and chemical admixtures such as lithium salts to prevent expansion caused by ASR was first reported 70 years ago, shortly after the discovery of ASR in 1940s. Despite numerous investigations, the understanding of the mechanisms of Al and Li for mitigating ASR remain partially inexplicit in the case of Al, and hardly understood in the case of Li. This paper reviews the available information on the effect of Al and Li on ASR expansion, the influencing factors, possible mechanisms and limitations. The role of Al in mitigating ASR is likely related to the reduction of dissolution rate of reactive silica. Moreover, the presence of Al may alter the structure of crystalline ASR products to zeolite or its precursor, but such effect seems to be not that significant at ambient conditions due to the slow kinetics of zeolite formation. Several mechanisms for the lithium salts in mitigating ASR have been proposed, but most of them are not conclusive primarily due to the lack of knowledge about the formed reaction products. Combination of Al-rich SCMs and lithium salts may be used as an economic solution for ASR mitigation, although systematic studies are necessary prior to the applications.

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