Fmoc-N-amido-PEG36-t-butyl ester is a PEG-based PROTAC linker with the molecular formula C₉₄H₁₆₉NO₄₀ and a molecular weight of 1953.33. Its structure consists of an Fmoc protecting group, an amide bond, 36 ethylene glycol repeating units, and a t-butyl ester terminal group, offering a balanced combination of hydrophilicity and hydrophobicity. The production process involves multi-step organic synthesis, including the condensation reaction between Fmoc-NHS ester and amino-PEG36-t-butanol, with strict control of reaction conditions (such as temperature and pH) to prevent by-products. This reagent is primarily used in PROTAC molecule synthesis, where it connects E3 ubiquitin ligase ligands with target protein ligands to enable degradation of target proteins via the ubiquitin-proteasome system, holding significant academic value in cancer targeted therapy and drug development.