Inhibitors of Human Histone Deacetylase:  Synthesis and Enzyme and Cellular Activity of Straight Chain Hydroxamates

Inhibitors of histone deacetylase (HDAC) have been shown to induce terminal differentiation of human tumor cell lines and to have antitumor effects in vivo. We have prepared analogues of suberoylanilide hydroxamic acid (SAHA) and trichostatin A and have evaluated them in a human HDAC enzyme inhibition assay, a p21<sup>waf1</sup> (p21) promoter assay, and in monolayer growth inhibition assays. One compound, 4-(dimethylamino)-<i>N</i>-[7-(hydroxyamino)-7-oxoheptyl]-benzamide, was found to affect the growth of a panel of eight human tumor cell lines differentially.