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