N.epsilon.-[[2-(Trimethylsilyl)ethoxy]carbonyl] derivatives of tri-L-lysine and tetra-L-lysine as potential intermediates in the block polymer synthesis of macromolecular drug conjugates
N.epsilon.-[[2-(Trimethylsilyl)ethoxy]carbonyl] derivatives of tri-L-lysine and tetra-L-lysine as potential intermediates in the block polymer synthesis of macromolecular drug conjugates