2-(Prop-2-yn-1-yloxy)-4-(3-(trifluoromethyl)-3H-diazirin-3-yl)benzoic acid is used for chemical probe synthesis, this trifunctional building block contains a light-activated diazirine, alkyne tag, and carboxylic acid synthetic handle. When appended to a ligand or pharmacophore through its acid linker, this building block allows for UV light-induced covalent modification of a biological target with potential for downstream applications via the alkyne tag. Use alone or in parallel with othermulti-functional building blocksto discover the optimal probe for your chemical biology experiments.