Poly(ethylene glycol)-Prodrug Conjugates: Concept, Design, and Applications
Figure 7
(a) mPEG-based protein-modifying methods. Protein modification with all of these agents results in acylated amine-containing linkages: amides, derived from active esters 3–6 and 11, or carbamates, derived from 7 to 10. Alkylating reagents 12 and 13 react with proteins forming secondary amine conjugation with amino-containing residues. As represented in (b) tresylate 12 alkylates directly, while acetaldehyde (13) is used in reductive alkylation reactions. The numbering (1–13) represent to the order in which these activated polymers were introduced (reproduced from [6, 36]).
