Synthesis and ligation ability of mono-aminooxy-functionalized dendrigraft poly-l-lysine (DGL)

A bifunctional tetraethylene glycol (TEG) linker was prepared and used as an initiator for the synthesis of the first two generations of dendrigraft poly-l-lysines (DGL). The key steps involved the desymmetrization of TEG by introduction of an amine group after activation of a terminal hydroxyl group and of a conveniently protected aminooxy functionality at the other end. Initiation of l-lysine N-carboxyanhydride polymerization by the terminal amine yielded generations 1 and 2 of DGL in which a subsequent functionalization of the aminooxy group by ligation with entities bearing an aldehyde group turned out to be feasible.

Graphical abstractA bifunctional linker was prepared and used as an initiator for the synthesis of dendrigraft poly-l-lysine generations and shown to undergo a selective ligation with aldehydes.Download full-size image