2- (2- (2-Aminoethoxy) ethoxy) acetic acid hydrochloride

2- (2- (2-Aminoethoxy) ethoxy) acetic acid hydrochloride (AEEA·HCl) is a hydrophilic linker containing an amino group and a short-chain PEG structure, and exhibits a certain degree of reactivity, and 2- (2- (2-Aminoethoxy) ethoxy) acetic acid hydrochloride (AEEA·HCl) is commonly employed as a short-chain linker unit in PROTAC design to enhance molecular water solubility and increase flexibility, thereby optimizing physicochemical properties and biocompatibility.