Carboxylates. reactivity

Carboxylate-Reactive Cascade Blue Cadaverine and Cascade Blue Ethylenediamine... 

Further work with the same dye (7.43) and carbodiimides (7.44 and 7.45) concentrated on this problem of limited efficiency. Cotton fabric padded with the dye phosphonate solution was aftertreated with the carbodiimide dissolved in various alcoholic solutions to avoid hydrolytic decomposition. Under these conditions cyanamide was much more effective than dicyandiamide. With conventional reactive dyes the efficiency of the dye-fibre reaction is limited by competing hydrolysis of the active dye. Although phosphonated or carboxylated reactive dyes do not hydrolyse, their level of fixation is limited by competing hydrolysis of the carbodiimide activator [46]. 

A carboxylate-reactive cross-linking compound typically contains a primary amine functional group that can be coupled to a carboxylic acid group in a protein or other molecule through the use of a suitable activating agent, such as a carbodiimide. The carbodiimide forms an active ester intermediate that then reacts with the amine to create an amide bond (Chapter 3, Section 1). Recent reported use of diazoalkyl deriva-... 

Aryl Esters 2,6-Di-re/t-butyl-4-methylphenyl esters (BHT esters) and 2,6-di-tert-butyl-4-methoxyphenyl esters (BHA esters) provide steric suppression of the carboxyl reactivity so they do not react with RMgX or RLi reagents.BHT and BHA esters... 

In addition, bioconjugation of fluorescent probes may be enabled through a variety of functional group activation chemistries as a means to facilitate bioconjugation. For instance, carboxyl-reactive probes can combine with carboxyl groups in proteins, peptides. 

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