Polymeric reagents are provided comprising a moiety of atoms arranged in a specific order, wherein the moiety is positioned between a water-soluble polymer and a reactive group. The polymeric reagents are useful for, among other things, forming polymer-active agent conjugates. Related methods, compositions, preparations, and so forth are also provided.
                            聚合物试剂由按特定顺序排列的原子分子组成,其中原子分子位于
水溶性聚合物和活性基团之间。这些聚合物试剂主要用于形成聚合物-活性剂共轭物。还提供了相关的方法、组合物、制剂等。