"Clip" and "click" chemistries combination: toward easy PEGylation of degradable aliphatic polyesters

a-Methoxy-v-alkyne poly(ethylene glycol) (PEG) was tagged with pendent N-hydroxy-succinimidyl activated esters by photografting of a molecular clip. This easily synthesized heterofunctional PEG was found to be a versatile building block for (i) conjugation with an amino derivative and (ii) grafting to azido functional aliphatic polyesters backbone by Huisgen’s 1,3- dipolar cycloaddition. This original combination of ‘‘clip’’ and ‘‘click’’ reactions provides a versatile and straightforward pathway for the synthesis of functional amphiphilic and degradable copolymers valuable for biomedical applications such as in drug-delivery