Products with TCO

The reaction between a tetrazine (Tz) and a trans-cyclooctene (TCO) is the innovative third generation Click reaction that proceeds without the use of copper or other catalyst. It is rapid, fully bioorthogonal and excels at very low concentrations. Moreover, the tetrazine-TCO ligation can be performed in aqueous media. Mechanistically, this reaction proceeds via an inverse electron-demand Diels-Alder cycloaddition reaction between a tetrazine and a strained alkene such as trans-cyclooctene (TCO), cyclopropane or norbornene, followed by a retro-Diels-Alder reaction under elimination of dinitrogen, the latter rendering the reaction irreversible.