Abexinostat is a broad-spectrum phenyl hydroxamic acid inhibitor of histone deacetylase (HDAC) with potential antineoplastic activity. It inhibits several isoforms of HDAC, resulting in an accumulation of highly acetylated histones, followed by the induction of chromatin remodeling. Abexinostat has been shown to inhibit homologous recombination (HR) activity by inhibiting the expression of RAD51. RAD51, a homologue of bacterial RecA, assists in the repair of DNA double-strand breaks (DSBs). MW: 397.42. Purity ≥96% by HPLC