| abstract |
Polymeric reagent of formula V: ** Formula ** in which: POLY1 is a first poly (ethylene glycol) having a molecular weight in the range of more than 5,000 Daltons to 100,000 Daltons; POLY2 is a second poly (ethylene glycol) having a molecular weight in the range of more than 5,000 Daltons to 100,000 Daltons; X1 is a first spacer residue; X2 is a second spacer residue; H is an ionizable hydrogen atom; R1 is H or an organic radical; R2 is H or an organic radical; (a) it is either zero or one; (b) it is either zero or one; Re1, when present, is a first group of electron alteration; Re2, when present, is a second group of electron alteration; and (FG) is a functional group that can react with an amino group of an active ingredient to form a degradable bond. |