Tos-PEG-methyl ester is characterized by the presence of a tosylate functional group (-OTs) attached to one end of a PEG chain and a methyl ester (-COOCH3) at the other end.
The tosylate group in Tos-PEG-methyl ester is a leaving group that can be easily displaced by a nucleophile, making it a useful tool in chemical synthesis. The methyl ester group, on the other hand, is an ester linkage that can be hydrolyzed by esterases in vivo, leading to the release of the PEG chain and the attached molecule. This property makes Tos-PEG-methyl ester an attractive candidate for drug delivery applications.
Tos-PEG-methyl ester has been extensively used in the development of prodrugs, which are inactive or less active forms of a drug that can be converted into the active form in vivo. By attaching the drug molecule to Tos-PEG-methyl ester via a labile bond, the prodrug can be delivered to the target site and undergo enzymatic hydrolysis to release the active drug molecule. This approach can improve drug solubility, enhance bioavailability, and reduce toxicity.