Preparation of 3-azidocoumarins and alkyne-analogues of fatty acids for click chemistry.

Abstract

Click chemistry is evolving as a powerful tool in biological applications because it allows the sensitive and specific detection of compounds with alkyne or azido groups. Particularly, this click-chemistry-based method has been applied to the tracing of fatty acid metabolism. Fatty acids are abundant constituents of all biological systems, and their metabolism is important for normal function at all levels of an organism. Changes in fatty acid metabolism can cause severe diseases and have become a focus of recurrent research. The present work deals with the synthesis and characterization of two known compounds: the fluorogenic dye 3-azido-7-hydroxycoumarin bearing an azido group and an alkyne-analogue of a fatty acid. Those compounds could be useful for the study of fatty acids metabolism because they allow to form “in situ” a triazole derivate with fluorescence activity which can be detected and quantified. Introduction of a small terminal triple bond does not significantly disturb the chain structure and it allows to trace the fatty acid by a click reaction with the azido coumarin. Thus, a fluorescent compound is formed containing a triazole moiety which can be detected and quantified once the cell has been exposed to the alkyne-analogue and metabolites have reacted with the profluorophore. Both products have been sent to the biochemical research group leaded by Dra. Casals in the Universitat Internacional de Catalunya (UIC) to study the activity of carnitine palmitoyltransferase I enzyme (CPT1) by this method involving click reaction.