Aminooxy-PEG-t-butyl ester is a compound that belongs to the family of polyethylene glycol (PEG) derivatives, which are widely used in the field of pharmaceutical research and development. The Aminooxy functional group is a reactive group that can be used for conjugation with various biomolecules, such as proteins and peptides, to enhance their solubility, stability, and pharmacokinetic properties. The t-butyl ester group is a protecting group that helps to stabilize the Aminooxy functionality during the synthesis process. By incorporating Aminooxy-PEG-t-butyl ester into drug molecules, researchers can increase the bioavailability of the drug and target specific tissues or cells. Furthermore, the use of PEG derivatives in pharmaceuticals can help to reduce the toxicity and immunogenicity of the drug, making it a valuable tool for drug delivery and development.