Mal-PEG-t-butyl ester is a derivative of polyethylene glycol (PEG) that contains a maleimide functional group (-Mal) at one end and a t-butyl ester (-OC(t-Bu)3) at the other end. This compound has gained significant attention in the field of pharmaceutical research and development due to its ability to selectively react with thiols, such as cysteine residues in proteins.
The maleimide group in Mal-PEG-t-butyl ester is known for its high reactivity towards thiols, forming stable thioether bonds. This reactivity has been utilized in the development of novel drug conjugates, such as antibody-drug conjugates (ADCs) and protein-polymer conjugates. In these systems, the Mal-PEG-t-butyl ester is covalently attached to the drug or protein of interest via a thiol-maleimide reaction, resulting in improved pharmacokinetics and targeted delivery.
The t-butyl ester group in Mal-PEG-t-butyl ester provides a convenient protecting group for the maleimide group during synthesis and storage, as it can be easily removed under mild conditions to expose the reactive maleimide group. This feature makes Mal-PEG-t-butyl ester a versatile tool for the development of a wide range of drug delivery systems and diagnostic agents.