PEG derivatives having an amidocarbonate linkage

摘要

Polymeric reagents are disclosed comprising a moiety of atoms arranged in a specific order, wherein the moiety is positioned between a water-soluble polymer and a reactive group. Typical examples the polymeric reagent include the compounds of formula (II) and formula (III). The polymeric reagents are useful for, among other things, forming polymer-active agent conjugates. Related methods, compositions, preparations, and so forth are also disclosed.