Cyclohexane-PEG1-Br

Cyclohexane-PEG1-Br is a brominated cyclohexyl–polyethylene glycol linker designed to support PROTAC assembly by enabling efficient connection between a ligand and a binding partner. Its ether-containing PEG segment provides conformational flexibility and improved solubility, while the bromide handle enables straightforward derivatization under standard organic synthesis conditions. The following sections describe the molecule’s structural features and practical reactivity considerations for constructing targeted protein degradation conjugates.

Structure: The linker combines a cyclohexyl scaffold with a short polyethylene glycol ether segment, terminating in a bromomethyl group. It contains ether oxygen atoms that confer polarity and hydrogen-bonding capacity, alongside a saturated carbon framework and a carbon–bromine bond suitable for substitution chemistry.

Reactivity: The bromide functions as a leaving group for nucleophilic substitution reactions, making it suitable for installing the linker onto ligand-derived nucleophiles (for example, amines or oxygen nucleophiles) via SN2-type pathways. Typical conditions employ polar aprotic solvents and base-mediated deprotonation to generate the reactive nucleophile. Reaction temperatures are selected to balance substitution efficiency and minimize side reactions, and product purification commonly relies on standard chromatographic or extraction workflows.