Acid-PEG-t-Butyl Ester

Acid-PEG-t-butyl ester is a heterobifunctional reagent featuring a carboxylic acid and a protected tert-butyl ester, designed for asymmetric conjugation strategies where one end is readily available for amidation while the other requires acidic deprotection for subsequent functionalization. Its key advantages include orthogonal reactivity for sequential modifications, tunable spacer length (n), and protection of one carboxyl group during synthetic steps, though the t-Bu ester necessitates acidic deprotection for full functionality.