Crisaborole intermediate

5-(4-(Hydroxyl Methyl)phenoxy)benzo[c][1,2]oxaborol-1-(3H)-ol is an impurity for Crisaborole(H947928). Crisaborole is a series of phenoxy benzoxaboroles were synthesized and screened for their inhibitory activity against PDE4 and cytokine release. 5-?(4-?Cyanophenoxy)?-?2,?3-?dihydro-?1-?hydroxy-?2,?1-?benzoxaborole (AN2728) showed potent activity both in vitro and in vivo. AN2728 is being studied as an anti-inflammatory agent.