Amino-PEG2-propionic acid

This amino-PEG2-propionic acid linker is designed for modular PROTAC assembly, providing a hydrophilic, flexible spacer that can improve solubility and help position target-binding warheads for productive ternary complex formation. Its functional handles support reliable conjugation strategies commonly used in targeted protein degradation workflows. The following sections describe the linker’s structural characteristics and practical reactivity considerations in detail.

Structure: The linker combines an amino functionality with a short polyethylene glycol segment and a propionic acid group, enabling formation of stable amide or related linkages. It contains ether linkages typical of PEG chains, plus carboxylic acid and primary amine groups for controlled coupling chemistry.

Reactivity: The propionic acid enables carboxyl-activation approaches such as carbodiimide-mediated coupling to amine-bearing partners, typically using standard coupling reagents and base in polar aprotic solvents. The amino group can also be used for amide formation with activated carboxylic acids. Reaction conditions should be optimized to preserve PEG integrity and minimize side reactions such as hydrolysis of activated intermediates.