Tetrazine Acid

Tetrazine Acid demonstrates exceptionally fast cycloaddition kinetics (up to 30 000 M-1 s-1) with trans-cyclooctene (TCO) as the dienophile, the fastest kinetics ever reported for any bioorthogonal reaction. The chemical stability tetrazines is substantially lower compared to methyltetrazines, which requires more careful selection of reagents and conditions for chemical transformation, however it is in acceptable range for many applications.