Calreticulin transacetylase: A novel enzyme-mediated protein acetylation by acetoxy derivatives of 3-alkyl-4-methylcoumarins

► CRTAase substrate specificities of C-3 alkyl acetoxycoumarins were studied. ► The potency of diacetoxy coumarins was almost twice the monoacetoxy counterparts. ► The increase in size of the C-3 alkyl group decreases the CRTAase activity.