Thermolabile Protecting Groups (TPGs) are applied in
chemical synthesis
Chemical synthesis (chemical combination) is the artificial execution of chemical reactions to obtain one or several products. This occurs by physical and chemical manipulations usually involving one or more reactions. In modern laboratory uses ...
when mild
deprotection
A protecting group or protective group is introduced into a molecule by chemical modification of a functional group to obtain chemoselectivity in a subsequent chemical reaction. It plays an important role in multistep organic synthesis.
In man ...
conditions are required. Their removal merely consists of increasing temperature, which leads to deprotection of the protected sensitive part of a molecule.
The deprotection mechanism has been proven only for several Thermolabile Protecting Groups (TPGs). Most of these groups are removed on the basis of
intramolecular cyclization depending either on nucleophilicity or configuration. TPGs are characterized by a different half-life after increasing temperature by 70 °C. The shortest deprotection time with high stability in lower temperatures has been found for 2-
pyridyl
Pyridine is a basic heterocyclic organic compound with the chemical formula . It is structurally related to benzene, with one methine group replaced by a nitrogen atom . It is a highly flammable, weakly alkaline, water-miscible liquid with a ...
TPGs
that are applied to protect a
hydroxyl group
In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ...
, carboxylic acid or a phosphate esters. For these groups stabilization systems have been developed depending on the protected part of a molecule: for a phosphate centre it is the "click-clack" approach, and for a hydroxyl group – the "chemical switch" concept.
TPGs are applied as an element that increases the specificity of starters in
PCR; they may also be used in
microarray
A microarray is a multiplex (assay), multiplex lab-on-a-chip. Its purpose is to simultaneously detect the expression of thousands of biological interactions. It is a two-dimensional array on a Substrate (materials science), solid substrate—usu ...
construction.
[Grajkowski A.; Cieślak J., Chmielewski M.K., Marchán V., Phillips, L. R., and Beaucage, S. L., Wilk A.; „Conceptual “Heat-Driven” approach to the synthesis of DNA oligonucleotides on microarrays” Ann. N.Y. Acad. Sci., 1002, 1-11 (2003)]
References
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Chemical synthesis
Protecting groups