Ald-CH2-PEG10-Boc

Ald-CH2-PEG10-Boc is a functional PEG-based linker designed for modular PROTAC construction, combining an aldehyde handle with a tert-butyl ester-protected carboxylic acid for controlled conjugation. Its flexible poly(ethylene glycol) segment supports productive ternary-complex formation by improving solubility and conformational adaptability, while the tert-butyl ester-protected functionality enables stepwise synthesis. The aldehyde group provides a reactive electrophile for forming stable linker–ligand connections, and the subsequent points below describe the structure and reactivity in detail.

Structure: The linker contains a PEG chain providing hydrophilic flexibility, terminated with an aldehyde and a methylene spacer. A tert-butyl ester-protected carboxyl group is present. Overall, it features ether linkages along the PEG backbone and a reactive aldehyde carbonyl.

Reactivity: The aldehyde can participate in condensation or reductive amination chemistry to connect PROTAC ligands bearing appropriate nucleophiles, typically under mild, anhydrous conditions to limit aldehyde side reactions. The tert-butyl ester enables orthogonal protection during coupling steps and can be removed under standard acid-mediated deprotection to reveal a carboxylic acid for subsequent conjugation. Suitable solvents include polar aprotic or alcohol-containing media, and catalysts depend on the chosen coupling strategy.