Aminooxy-PEG-NH-Boc is a compound that contains functional groups such as an aminooxy group, a PEG linker, and a Boc-protected amino group. This molecule has gained significant attention in pharmaceutical research and development due to its ability to selectively modify biomolecules such as proteins and peptides. The aminooxy group specifically reacts with carbonyl groups, such as ketones or aldehydes, to form a stable oxime linkage. This chemical reaction is widely used in drug discovery and development for the conjugation of small molecule drugs to biomolecules, such as antibodies or enzymes, to improve drug efficacy and selectivity. Additionally, the PEG linker provides solubility and stability to the resulting conjugate, while the Boc-protected amino group can be deprotected to introduce additional functional groups or modify the conjugation site.