Synthesis and tritium labeling of new aromatic diazirine building blocks for photoaffinity labeling and cross-linking

The synthesis of three bifunctional 3-phenyl-3-(trifluoromethyl)diazirinyl building blocks is described. These compounds were designed for their poten tial chemical reactivity toward a wide range of functional groups occurring in proteins and small molecules. Moreover, we also synthesized the tritiat ed versions of these three building blocks, using a recently reported chemo selective and regiospecific key-reaction. These building blocks represent a new family of radiolabeled molecules that can be utilized as photoactivata ble tags for labeling of proteins or small molecules by using crosslinking or site-directed photoaffinity labeling techniques.