{HEAD ~ The 1 benzotriazolylcarbonate ester} can then be reacted directly with a biologically active agent to form a biologically active polymer conjugate or reacted with {TAIL ~ an amino acid}, such as lysine, to form an amino acid derivative 
reacted with
{ HEAD ~ The 1 benzotriazolylcarbonate ester } can then be reacted directly with a biologically active agent to form a biologically active polymer conjugate or reacted with { TAIL ~ an amino acid } , such as lysine , to form an amino acid derivative
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH