Borinic acid-catalyzed stereo- and site-selective synthesis of β-glycosylceramides

2017 ◽  
Vol 53 (44) ◽  
pp. 5978-5980 ◽  
Author(s):  
Kyan A. D’Angelo ◽  
Mark S. Taylor
Keyword(s):  
Human Health ◽  
Acid Catalysis ◽  
Selective Synthesis ◽  
Health And Disease ◽  
Acid Catalyzed ◽  
Site Selective ◽  
Glycosyl Donors ◽  
Borinic Acid

Diphenylborinic acid catalysis enables the direct, stereo- and site-selective coupling of glycosyl donors with ceramide lipids. The β-1,1′-linkages accessed through this method are characteristic of mammalian glycosphingolipids that play diverse roles in physiology, human health and disease.

scholarly journals Synergistic Brønsted/Lewis Acid Catalyzed Aromatic Alkylation with Unactivated Tertiary Alcohols or Di-tert-Butylperoxide to Synthesize Quaternary Carbon Centers

2021 ◽  
Author(s):  
Aaron Pan ◽  
Maja Chojnacka ◽  
Robert Crowley ◽  
Lucas Gottemann ◽  
Brandon Haines ◽  
...  
Keyword(s):  
Dft Calculations ◽  
Lewis Acid ◽  
Acid Catalysis ◽  
Alkylating Agents ◽  
Environmentally Benign ◽  
Quaternary Carbon ◽  
Tertiary Alcohols ◽  
Carbon Centers ◽  
Acid Catalyzed ◽  
Site Selective

Dual Brønsted/Lewis acid catalysis involving environmentally benign, readily accessible protic acid and iron promotes site-selective tert-butylation of electron-rich arenes using di-tert-butylperoxide. This transformation inspired the development of a synergistic Brønsted/Lewis acid catalyzed aromatic alkylation that fills a gap in the Friedel–Crafts reaction literature by employing unactivated tertiary alcohols as alkylating agents, leading to new quaternary carbon centers. Corroborated by DFT calculations, the Lewis acid serves a role in enhancing the acidity of the Brønsted acid. The use of non-allylic, non-benzylic, and non-propargylic tertiary alcohols represents an underexplored area in Friedel–Crafts reactivity.

Cobalt/Lewis Acid Catalysis for Hydrocarbofunctionalization of Alkynes via Cooperative C–H Activation

2020 ◽  
Author(s):  
Chang-Sheng Wang ◽  
Sabrina Monaco ◽  
Anh Ngoc Thai ◽  
Md. Shafiqur Rahman ◽  
Chen Wang ◽  
...  
Keyword(s):  
Catalytic System ◽  
Lewis Acid ◽  
Hydrogen Transfer ◽  
Acid Catalysis ◽  
Rate Limiting Step ◽  
Site Selectivity ◽  
Set Up ◽  
Site Selective ◽  
First Time ◽  
Rate Limiting

A catalytic system comprised of a cobalt-diphosphine complex and a Lewis acid (LA) such as AlMe3 has been found to promote hydrocarbofunctionalization reactions of alkynes with Lewis basic and electron-deficient substrates such as formamides, pyridones, pyridines, and azole derivatives through site-selective C-H activation. Compared with known Ni/LA catalytic system for analogous transformations, the present catalytic system not only feature convenient set up using inexpensive and bench-stable precatalyst and ligand such as Co(acac)3 and 1,3-bis(diphenylphosphino)propane (dppp), but also display distinct site-selectivity toward C-H activation of pyridone and pyridine derivatives. In particular, a completely C4-selective alkenylation of pyridine has been achieved for the first time. Mechanistic stidies including DFT calculations on the Co/Al-catalyzed addition of formamide to alkyne have suggested that the reaction involves cleavage of the carbamoyl C-H bond as the rate-limiting step, which proceeds through a ligand-to-ligand hydrogen transfer (LLHT) mechanism leading to an alkyl(carbamoyl)cobalt intermediate.

scholarly journals Plant-Derived Extracellular Vesicles: Current Findings,Challenges, and Future Applications

Membranes ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 411
Author(s):  
Nader Kameli ◽  
Anya Dragojlovic-Kerkache ◽  
Paul Savelkoul ◽  
Frank R. Stassen
Keyword(s):  
Human Health ◽  
Extracellular Vesicles ◽  
Preliminary Results ◽  
In Vivo Experiments ◽  
Health And Disease ◽  
Conducting Research ◽  
Protocol Standardization ◽  
Insight Into

In recent years, plant-derived extracellular vesicles (PDEVs) have gained the interest of many experts in fields such as microbiology and immunology, and research in this field has exponentially increased. These nano-sized particles have provided researchers with a number of interesting findings, making their application in human health and disease very promising. Both in vitro and in vivo experiments have shown that PDEVs can exhibit a multitude of effects, suggesting that these vesicles may have many potential future applications, including therapeutics and nano-delivery of compounds. While the preliminary results are promising, there are still some challenges to face, such as a lack of protocol standardization, as well as knowledge gaps that need to be filled. This review aims to discuss various aspects of PDEV knowledge, including their preliminary findings, challenges, and future uses, giving insight into the complexity of conducting research in this field.

scholarly journals Science for the Next Century: Deep Phenotyping

2021 ◽  
pp. 002203452110018
Author(s):  
J.T. Wright ◽  
M.C. Herzberg
Keyword(s):  
Health Care ◽  
Human Health ◽  
Care Delivery ◽  
The Past ◽  
Large Populations ◽  
Health And Disease ◽  
Methodological Approaches ◽  
Omic Data ◽  
Precision Health ◽  
Deep Phenotyping

Our ability to unravel the mysteries of human health and disease have changed dramatically over the past 2 decades. Decoding health and disease has been facilitated by the recent availability of high-throughput genomics and multi-omics analyses and the companion tools of advanced informatics and computational science. Understanding of the human genome and its influence on phenotype continues to advance through genotyping large populations and using “light phenotyping” approaches in combination with smaller subsets of the population being evaluated using “deep phenotyping” approaches. Using our capability to integrate and jointly analyze genomic data with other multi-omic data, the knowledge of genotype-phenotype relationships and associated genetic pathways and functions is being advanced. Understanding genotype-phenotype relationships that discriminate human health from disease is speculated to facilitate predictive, precision health care and change modes of health care delivery. The American Association for Dental Research Fall Focused Symposium assembled experts to discuss how studies of genotype-phenotype relationships are illuminating the pathophysiology of craniofacial diseases and developmental biology. Although the breadth of the topic did not allow all areas of dental, oral, and craniofacial research to be addressed (e.g., cancer), the importance and power of integrating genomic, phenomic, and other -omic data are illustrated using a variety of examples. The 8 Fall Focused talks presented different methodological approaches for ascertaining study populations and evaluating population variance and phenotyping approaches. These advances are reviewed in this summary.

Borinic acid catalyzed α-addition to isocyanide with aldehyde and water

2011 ◽  
Vol 52 (20) ◽  
pp. 2557-2559 ◽  
Author(s):  
Takahiro Soeta ◽  
Yuuki Kojima ◽  
Yutaka Ukaji ◽  
Katsuhiko Inomata
Keyword(s):  
Acid Catalyzed ◽  
Borinic Acid

An environmentally benign cascade reaction of chromone-3-carboxaldehydes with ethyl 2-(pyridine-2-yl)acetate derivatives for highly site-selective synthesis of quinolizines and quinolizinium salts in water

2020 ◽  
Vol 22 (20) ◽  
pp. 6943-6953 ◽  
Author(s):  
Li Chen ◽  
Rong Huang ◽  
Kun Li ◽  
Xing-Han Yun ◽  
Chang-Long Yang ◽  
...  
Keyword(s):  
Cascade Reaction ◽  
Environmentally Benign ◽  
Selective Synthesis ◽  
Site Selective ◽  
Reaction In Water

A protocol for the synthesis of quinolizines from ethyl 2-(pyridine-2-yl)acetates via an unprecedented cascade reaction in water was constructed.

scholarly journals Vitamin C in Human Health and Disease

Nutrients ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1595
Author(s):  
Dariusz Nowak
Keyword(s):  
Eighteenth Century ◽  
Vitamin C ◽  
Human Health ◽  
Citrus Fruit ◽  
Ancient Egypt ◽  
Vitamin Supplement ◽  
Vitamin C Deficiency ◽  
Health And Disease

Although the symptoms related to vitamin C deficiency were known in ancient Egypt and eighteenth century Scottish surgeon James Lind found that scurvy (a disease resulting from insufficient dietary ingestion of vitamin C) could be effectively treated with citrus fruit, this vitamin was discovered only in the year 1912 and then after 21 years it was chemically synthetized and introduced to the market as the first vitamin supplement [...]

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