Formation of internucleotide 3′-5′ phosphoramidate links by direct coupling of phosphoryl and amino groups

Abstract
The stepwise synthesis of oligomers derived from 5′-amino-5′-deoxythymidine 3′-phosphate and 5′-amino-5′-deoxy-3′-O-mono-P-methoxytritylthymidine is described. The internucleotide phosphoramidate links were formed by condensation of nucleoside 3′-phosphates with aminonucleosides by means of triphenylphosphine and dipyridyl disulfide.