Synthesis and reactions of protected aminoacyl ethyl phosphates

grantor: University of TorontoAminoacyl adenylates are enzyme bound intermediates in the synthesis of aminoacyl t-RNA's. Aminoacyl t-RNA's are then used by the cell in protein biosynthesis. Aminoacyl ethyl phosphates, analogues of aminoacyl adenylates, have been prepared as a means to study the reactivity of this class of compounds. Aminoacyl ethyl phosphates react with amines and alcohols, making them excellent candidates for potential use in aqueous peptide synthesis and the chemical aminoacylation of t-RNA. Aminoacyl ethyl phosphates can be produced by using dicyclohexylcarbodiimide to couple N-protected amino acids with tetraethylammonium ethyl phosphate. The tetraethylammonium cation can then be replaced using ion exchange procedures. Different salts of aminoacyl ethyl phosphates were examined for their potential use in peptide synthesis and for the chemical aminoacylation of t-RNA. The sodium salt of N-t-Boc-alanyl ethyl phosphate reacts rapidly with alanine in aqueous solution to from the dipeptide N-t-Boc-alanyl-alanine in high yield. Sodium N-t-Boc aminoacyl ethyl phosphates also react with lower alcohols and diols in water to form the corresponding amino acid esters. Divalent metal ions increase the reactivity of aminoacyl ethyl phosphates toward alcohols in aqueous solution. This may provide a route to the chemical aminoacylation of t-RNA.M.Sc