CRA-026440 hydrochloride is a potent, broad-spectrum HDAC ( HDAC ) inhibitor. The K i values against recombinant HDAC isoenzymes HDAC1 , HDAC2 , HDAC3 , HDAC6 , HDAC8 , and HDAC10 are 4 nM, 14 nM, 11 nM, 15 nM, 7 nM, and 20 nM respectively. CRA-026440 hydrochloride shows antitumor and antiangiogenic activities. CRA-026440 (hydrochloride) is a click chemistry reagent, it contains an Alkyne group and can undergo copper-catalyzed azide-alkyne cycloaddition (CuAAc) with molecules containing Azide groups.