ChemInform Abstract: Powerful Amino Acid Derived Bifunctional Phosphine Catalysts Bearing a Hydrogen Bond Donor in Asymmetric Synthesis

ChemInform ◽  
2013 ◽  
Vol 44 (52) ◽  
pp. no-no
Author(s):  
Li-Wen Xu
Keyword(s):  
Hydrogen Bond ◽  
Amino Acid ◽  
Asymmetric Synthesis ◽  
Hydrogen Bond Donor

scholarly journals Chiral Thioureas—Preparation and Significance in Asymmetric Synthesis and Medicinal Chemistry

Molecules ◽  
2020 ◽  
Vol 25 (2) ◽  
pp. 401 ◽  
Author(s):  
Franz Steppeler ◽  
Dominika Iwan ◽  
Elżbieta Wojaczyńska ◽  
Jacek Wojaczyński
Keyword(s):  
Hydrogen Bond ◽  
Drug Development ◽  
Asymmetric Synthesis ◽  
Stereoselective Synthesis ◽  
Strong Hydrogen Bond ◽  
Hydrogen Bond Donor ◽  
Drug Candidates ◽  
Current State ◽  
The Family ◽  
Donor Capability

For almost 20 years, thioureas have been experiencing a renaissance of interest with the emerged development of asymmetric organocatalysts. Due to their relatively high acidity and strong hydrogen bond donor capability, they differ significantly from ureas and offer, appropriately modified, great potential as organocatalysts, chelators, drug candidates, etc. The review focuses on the family of chiral thioureas, presenting an overview of the current state of knowledge on their synthesis and selected applications in stereoselective synthesis and drug development.

scholarly journals Novel amide-functionalized chloramphenicol base bifunctional organocatalysts for enantioselective alcoholysis of meso-cyclic anhydrides

2018 ◽  
Vol 14 ◽  
pp. 309-317 ◽  
Author(s):  
Lingjun Xu ◽  
Shuwen Han ◽  
Linjie Yan ◽  
Haifeng Wang ◽  
Haihui Peng ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Asymmetric Synthesis ◽  
Hydrogen Bond Donor ◽  
Cyclic Anhydrides ◽  
Enantioselective Alcoholysis

A family of novel chloramphenicol base-amide organocatalysts possessing a NH functionality at C-1 position as monodentate hydrogen bond donor were developed and evaluated for enantioselective organocatalytic alcoholysis of meso-cyclic anhydrides. These structural diversified organocatalysts were found to induce high enantioselectivity in alcoholysis of anhydrides and was successfully applied to the asymmetric synthesis of (S)-GABOB.

scholarly journals Amino Acid-Based Deep Eutectic Solvents in Biomass Processing - Recent Advances

2021 ◽  
Author(s):  
Gustavo Gomes ◽  
Renan Mattioli ◽  
Julio Cezar Pastre
Keyword(s):  
Hydrogen Bond ◽  
Amino Acid ◽  
Choline Chloride ◽  
Deep Eutectic Solvents ◽  
Chemical Conversion ◽  
Hydrogen Bond Donor ◽  
Hydrogen Bond Acceptor ◽  
Platform Chemicals ◽  
Biomass Processing ◽  
Solvent Systems

The use of non-conventional solvent systems, such as deep eutectic solvents (DES), for biomass processing is a growing interest. DES are formed by two or more components, usually solids at room temperature, which can interact with each other via hydrogen bonding, from a hydrogen bond acceptor (HBA) and a hydrogen bond donor (HBD), resulting in a liquid phase. The most studied HBA in the literature is choline chloride with several HBD and their use have been extensively reviewed. However, other abundant and natural HBA can be successfully applied on the preparation of different DES, e.g., amino acids. These amino acid-based DES have been used in biomass pretreatment, providing the fractionation of the main macromolecular components by lignin solubilization. In addition, amino acid-based DES can be applied in biomass chemical conversion to obtaining platform chemicals such as furanic derivatives. Bearing this in mind, this review focuses on exploring the use of amino acid-based DES on biomass processing, from pretreatment to chemical conversion.

scholarly journals The role of the hydroxy amino acid in the triplet sequence Asn-Xaa-Thr(Ser) for the N-glycosylation step during glycoprotein biosynthesis

1981 ◽  
Vol 195 (3) ◽  
pp. 639-644 ◽  
Author(s):  
E Bause ◽  
G Legler
Keyword(s):  
Hydrogen Bond ◽  
Amino Acid ◽  
Hydroxy Group ◽  
Catalytic Mechanism ◽  
Hydrogen Bond Donor ◽  
Hydrogen Bond Interaction ◽  
Hydrogen Bond Acceptor ◽  
Hydroxy Amino Acid ◽  
Hydroxy Amino

The catalytical role of the hydroxy amino acid in the “marker sequence” Asn-Xaa-Thr(Ser) for the N-glycosylation step of glycoprotein formation was investigated by using a series of hexapeptides derived from Tyr-Asn-Gly-Xaa-Ser-Val by substituting threonine, serine, cysteine, valine and O-methylthreonine respectively for Xaa. The results, which were obtained with calf liver microsomal fractions as enzyme source and dolichyl diphosphate di-N-acetyl [14C] chitobiose as glycosyl donor showed that the threonine-, serine- and cysteine-containing derivatives could be glycosylated, although at very different rates, whereas the valine and O-methylthreonine analogues did not work as glycosyl acceptors. Replacement of threonine by serine resulted in a 4-fold decrease in Vmax, and about a 10-fold increase in Km for glycosyl transfer. Replacement of serine by cysteine again decreased acceptor activity 2-3-fold. The various results, taken together, indicate an absolute requirement for a hydrogen-bond-donor function in the side chain of the hydroxy amino acid of the “marker sequence” and furthermore, point to a considerable influence of the structure of this amino acid on binding as well as on the glycosyl transfer itself. In order to explain the observed differences in the glycosyl-transfer rates, a model is proposed with a hydrogen-bond interaction between the amide of asparagine as the hydrogen-bond donor and the oxygen of the hydroxy group of the hydroxy amino acid as the hydrogen-bond acceptor. The participation of the hydroxy group in the catalytic mechanism of glycosyl transfer in the kind of proton-relay system is discussed.

Aliphatic Carboxylic Acid as Hydrogen-Bond Donor for Converting CO2 and Epoxide into Cyclic Carbonate under Mild Conditions

2021 ◽  
Author(s):  
Zheng Wang ◽  
Yajun Wang ◽  
Qianjie Xie ◽  
Zhiying Fan ◽  
Yehua Shen
Keyword(s):  
Hydrogen Bond ◽  
Carboxylic Acid ◽  
Value Added ◽  
Cyclic Carbonate ◽  
Hydrogen Bond Donor ◽  
Title Reaction ◽  
Aliphatic Carboxylic Acid ◽  
Mild Conditions ◽  
Atmospheric Carbon

The coupling of CO2 and epoxide is promising way to reduce atmospheric carbon by converting it into value-added cyclic carbonate. Pursuing efficient catalysts is highly attractive for the title reaction....

Role of the hydrogen bond donor component for a proper development of novel hydrophobic deep eutectic solvents

2019 ◽  
Vol 281 ◽  
pp. 423-430 ◽  
Author(s):  
Matteo Tiecco ◽  
Federico Cappellini ◽  
Francesco Nicoletti ◽  
Tiziana Del Giacco ◽  
Raimondo Germani ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Deep Eutectic Solvents ◽  
Hydrogen Bond Donor
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