Bioorthogonal Cleavage of Tetrazine-Caged Ethers and Esters Triggered by trans-Cyclooctene

In this study, we report the bioorthogonal cleavage of physiologically stable methylene tetrazines bearing an ether or ester linkage in the presence of trans-cyclooctene. Based on this approach, molecules with phenol or carboxylic acid moieties were efficiently released in a controlled manner, which can be effectively applied in living cells. We expect this bioorthogonal cleavage approach can be applied to several biomedical applications, including the development of antibody–drug conjugates, pretargeted prodrug release, and protein activation.