scholarly journals Lithium–Bromide Exchange versus Nucleophilic Addition of Schiff's base: Unprecedented Tandem Cyclisation Pathways

2019 ◽  
Vol 25 (51) ◽  
pp. 11876-11882
Author(s):  
Samantha A. Orr ◽  
Emily C. Border ◽  
Philip C. Andrews ◽  
Victoria L. Blair
Keyword(s):  
Nucleophilic Addition ◽  
Lithium Bromide ◽  
Schiff’S Base

scholarly journals Lithium–Bromide Exchange versus Nucleophilic Addition of Schiff's Base: Unprecedented Tandem Cyclisation Pathways

2019 ◽  
Vol 25 (51) ◽  
pp. 11796-11796
Author(s):  
Samantha A. Orr ◽  
Emily C. Border ◽  
Philip C. Andrews ◽  
Victoria L. Blair
Keyword(s):  
Nucleophilic Addition ◽  
Lithium Bromide ◽  
Schiff’S Base

Aldehyde gold clusters for molecular labeling

1995 ◽  
Vol 53 ◽  
pp. 858-859
Author(s):  
James F. Hainfeld ◽  
Frederic R. Furuya
Keyword(s):  
Covalent Bond ◽  
Aldehyde Group ◽  
Gold Clusters ◽  
Side Reactions ◽  
Amino Groups ◽  
Sodium Cyanoborohydride ◽  
Schiff’S Base ◽  
Protein Molecules ◽  
Hydroxysuccinimide Esters ◽  
Primary Amino

Glutaraldehyde is a useful tissue and molecular fixing reagents. The aldehyde moiety reacts mainly with primary amino groups to form a Schiff's base, which is reversible but reasonably stable at pH 7; a stable covalent bond may be formed by reduction with, e.g., sodium cyanoborohydride (Fig. 1). The bifunctional glutaraldehyde, (CHO-(CH2)3-CHO), successfully stabilizes protein molecules due to generally plentiful amines on their surface; bovine serum albumin has 60; 59 lysines + 1 α-amino. With some enzymes, catalytic activity after fixing is preserved; with respect to antigens, glutaraldehyde treatment can compromise their recognition by antibodies in some cases. Complicating the chemistry somewhat are the reported side reactions, where glutaraldehyde reacts with other amino acid side chains, cysteine, histidine, and tyrosine. It has also been reported that glutaraldehyde can polymerize in aqueous solution. Newer crosslinkers have been found that are more specific for the amino group, such as the N-hydroxysuccinimide esters, and are commonly preferred for forming conjugates. However, most of these linkers hydrolyze in solution, so that the activity is lost over several hours, whereas the aldehyde group is stable in solution, and may have an advantage of overall efficiency.

STUDY OF LAMINAR FORCED CONVECTION FOR DIFFERENT CONCENTRATIONS OF THE WATER-LITHIUM BROMIDE MIXTURE

2018 ◽  
Author(s):  
Allan Giuseppe ◽  
dhiego veloso ◽  
Carlos Antonio Cabral Santos ◽  
Pedro Gonçalves ◽  
Fábio Lima
Keyword(s):  
Forced Convection ◽  
Lithium Bromide ◽  
Laminar Forced Convection

Recent Progress in Chemosensors Using Aldehyde-bearing Fluorophores for the Detection of Specific Analytes and their Bioimaging

2019 ◽  
Vol 26 (21) ◽  
pp. 4003-4028 ◽  
Author(s):  
Fangjun Huo ◽  
Yaqiong Zhang ◽  
Caixia Yin
Keyword(s):  
Biomedical Research ◽  
Nucleophilic Addition ◽  
Recent Progress ◽  
Biological Imaging ◽  
Tissue Imaging ◽  
Fluorescence Probes ◽  
Biological Applications ◽  
Convenient Procedure ◽  
Nucleophilic Mechanism

In recent years, aldehyde-appended fluorescence probes have attracted increasing attention. Fluorescent biological imaging includes many modern applications for cell and tissue imaging in biomedical research. Meanwhile, the nucleophilic mechanism is a very simple and convenient procedure for the preparation of aldehyde-sensing probes. This tutorial review focuses on aldehyde-bearing chemosensors based on nucleophilic addition mechanism with biological applications.

Formation of spiro adduct from N-methyl-N-(2,4,6-trinitrophenyl)glycine anion

1989 ◽  
Vol 54 (2) ◽  
pp. 440-445 ◽  
Author(s):  
Vladimír Macháček ◽  
Alexandr Čegan ◽  
Miloš Sedlák ◽  
Vojeslav Štěrba
Keyword(s):  
Nmr Spectroscopy ◽  
Dimethyl Sulfoxide ◽  
Equilibrium Constant ◽  
Mole Fraction ◽  
Nucleophilic Addition ◽  
Adduct Formation ◽  
First Case ◽  
C Nmr

The intramolecular nucleophilic addition of N-methyl-N-(2,4,6-trinitrophenyl)glycine anion in methanol-dimethyl sulfoxide mixtures produces spiro[(3-methyl-5-oxazolidinone)-2,1'-(2',4',6'-trinitrobenzenide)]. The spiro adduct has been identified by means of 1H and 13C NMR spectroscopy. This is the first case when the formation of a Meisenheimer adduct with carboxylate ion is observed. Logarithm of the equilibrium constant of adduct formation increases linearly with the mole fraction of dimethyl sulfoxide in its mixture with methanol.

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