Synthesis of ketoprofen - L- phenylalanine and Ketoprofen -y- Aminobutyric acid ethyl esters as possible prodrugs

Ethyl ester HCI of the amino acids -L- phenylalanine and 7- Aminobutyric acid were synthesized through reaction of these amino acids with thionyl chloride in absolute ethanol. The amino group of these esters were allowd to react with the carboxylic acid functionality of ketoprofen (NSAID) using dicyclohexylcarbodiimide (DCC) as the condensing agent to form an amide linkage .These reactions were performd to synthesize the following compounds: Ketoprofen -L- phenylalanine ethyl ester, Ketoprofen - y- aminobutyric acid ethyl ester.The purity and identity of these possible prodrugs were supported by TLC, IR, and elemental microanalysis.This chemical approach to Ketoprofen physicochemical property modification based on enzyme specifications may offers a new and powerful approach for improving drug product efficacy.