Chemical. CAS 54711-38-5. Formula C14H17NO3. MW 247.29. 7-Diethylamino-4-hydroxymethylcoumarin DEACM is a photolabile compound that emits fluorescence upon irradiation and is used in analytical chemistry as a fluorescent probe. The photocleavable nature of DEACM facilitates its use as a photolabile protecting group for "Caged" bioactive molecules. The "caging" of bioactive molecule with photolabile protecting groups in particular has proven to be a useful tool in biochemical research. Caged compounds in which bioactive substances are inactivated with photolabile protecting groups and can be activated by UV or visible light photoirradiation. DEACM has been successfully applied for caging a wide variety of functional groups. It also has been used as a near infrared NIR light responsive chromophore.