Fluorescent 2'(3')-O-aminoacylnucleosides-acceptor substrates for ribosomal peptidyltransferase+.

2'(3')-O-L-Phenylalanylderivatives of fluorescent 1,N6-ethenoadenosine and 3,N4-ethenocytidine were prepared by chemical synthesis. Both compounds are good acceptor substrates in ribosomal peptidyltransferase reactions. Since these compounds cannot form Watson-Crick base pairs, the results indicate that the terminal aminoacyladenosine unit of AA-tRNA is bound to ribosomal protein on the acceptor site of peptidyltransferase and not to rRNA.