Thirty-six novel acylurea connected straight chain hydroxamates were designed and synthesized. Structure–activity relationships (SAR) were established for the length of linear chain linker and substitutions on the benzoylurea group. Compounds 5g, 5i, 5n, and 19 showed 10–20-fold enhanced HDAC1 potency compared to SAHA. In general, the cellular potency pIC50 (COLO205) correlates with enzymatic potency pIC50 (HDAC1). Compound ...