Notes:Our AmAz Coupler II allows for the linking of an amine-containing component to an azide-containing component. The amine-containing component is first reacted with the NHS ester and then the azide-containing component is reacted with the phosphine. An intramolecular trapping of the phosphorimidate by the ortho- methyl ester results in a stable aryl-1,4-diamide linkage between the two components.