3-(3-(but-3-ynyl)-3H-diazirin-3-yl)propanoic acid is a trifunctional building block for chemical probe synthesis, typically employed for photoaffinity labeling in chemical biology and medicinal chemistry. It contains a light-activated diazirine (photoreactive group), terminal alkyne tag (clickable handle), and carboxylic acid synthetic handle (connectivity group). When appended to a ligand or pharmacophore through its acid linker, this probe building block allows for UV light-induced covalent modification of a biological target with potential for downstream applications via the alkyne tag.
Tandem photoaffinity labeling–bioorthogonal conjugation in medicinal chemistry.
Design and synthesis of minimalist terminal alkyne-containing diazirine photo-crosslinkers and their incorporation into kinase inhibitors for cell- and tissue-based proteome profiling. 
Fluorescein Derivatives as Bifunctional Molecules for the Simultaneous Inhibiting and Labeling of FTO Protein. 
Fluorescent Probes for Single-Step Detection and Proteomic Profiling of Histone Deacetylases. 
Exploring the Binding Proteins of Glycolipids with Bifunctional Chemical Probes. 
Ligand and Target Discovery by Fragment-Based Screening in Human Cells.