Oligonucleotide protecting groups

摘要

Methods of preparing bis-protected guanidino groups of formula (IX)comprising the steps of reacting a compound of formula (VIII)with an amine, wherein R' is a thiopseudourea protecting group. Guanidino (IX) may then be used to add a guanidino functionality to other compounds, in particular those with a reactive hydroxyl group to give a protected functional group -NH-C(NH)-NH-CO-O-(CR5R6)N-CR3R4-Y-R2.