7-Azido-4-methylcoumarin

7-Azido-4-methylcoumarin is a fluorescent hydrogen sulfide (H2S) probe. 7-Azido-4-methylcoumarin serves as a highly sensitive assay for cystathionine β-synthase activity. It contains an azide group and can undergo copper-catalyzed azide-alkyne cycloaddition (CuAAc) with molecules containing alkyne groups. It can also undergo ring strain-promoted alkyne-azide cycloaddition (SPAAC) with molecules containing DBCO or BCN groups.