PD 0325901 is a hydroxamic acid ester derived from benzhydroxamic acid (N-hydroxybenzamide), with the hydroxamic acid group converted to a 2,3-dihydroxypropyl ester. The benzene ring is substituted at position 2 with a (2-fluoro-4-iodophenyl)amino group and at positions 3 and 4 with fluorines (R enantiomer). It functions as an EC 2.7.12.2 (mitogen-activated protein kinase kinase) inhibitor and an antineoplastic agent. It is also a secondary amino compound, a monofluorobenzene, an organoiodine compound, a propane-1,2-diol, and a difluorobenzene.
