1996 Bader Award Lecture - Aminoacyl ethyl phosphates. Biomimetically activated amino acids

Aminoacyl ethyl phosphates are functional analogues of aminoacyl adenylates, the activated intermediates formed by ribosomal enzymes from the reaction of amino acids with ATP. The aminoacyl ethyl phosphates are prepared by DCC-mediated coupling of a tetraalkyammonium salt of ethyl phosphate and an N-t-Boc-amino acid, followed by deprotection. The efficiency of the synthesis and the solubility properties of the product depend on the alkyl group in the ammonium counterion of the phosphate. N-Protected and free aminoacyl ethyl phosphates hydrolyze slowly (t(1/2), in neutral solution, 25 degrees C, similar to 100 h). These materials are potentially useful in biomimetic peptide synthesis, protein modification, and aminoacylation of RNA.