Synthesis of amino acyl adenylates using the tert-butoxycarbonyl protecting group

Alayl, [ 14c]-alanyl, phenylalanyl, and methionyl adenylates have been synthesized in high yields and relatively good purities. Elemental analysis 1H nmr and ir spectra have been utilized for the characterization of these extremely labile compounds. The present synthesis, which uses readily available N-tert-butoxycarbonyl amino acids, is compared with previous methods.