Methoxy-Tr-NH-PEG7

Methoxy-Tr-NH-PEG7 is a polyethylene glycol-based PROTAC linker designed to provide a flexible, hydrophilic spacer between a targeting ligand and an E3-recruiting module. Its ether-rich PEG scaffold supports favorable solubility and conformational adaptability, which can improve productive ternary complex formation in targeted protein degradation workflows. The detailed structural and synthetic considerations for using this linker in PROTAC construction are described below.

Structure: The linker features a PEG chain bearing ether linkages that confer pronounced hydrophilicity and segmental flexibility. A terminal methoxy substituent and an amide-type nitrogen functionality enable stable attachment points for conjugation. The overall architecture promotes water compatibility and reduces aggregation tendencies.

Reactivity: This linker is typically incorporated via amide or related coupling strategies using standard peptide-bond-forming reagents under mild base/activator conditions. Suitable solvents include polar aprotic media commonly used for amide formation, with temperature and time optimized to preserve sensitive targeting ligands. Mechanistically, activation of the carboxyl or corresponding functional group followed by nucleophilic substitution yields the PROTAC-ready conjugate while maintaining PEG integrity.