ABSTRACT
This Letter describes the discovery and key structure-activity relationship (SAR) of a series of 2-aminobenzimidazoles as potent Aurora kinase inhibitors. 2-Aminobenzimidazole serves as a bioisostere of the biaryl urea residue of SNS-314 (1c), which is a potent Aurora kinase inhibitor and entered clinical testing in patients with solid tumors. Compared to SNS-314, this series of compounds offers better aqueous solubility while retaining comparable in vitro potency in biochemical and cell-based assays; in particular, 6m has also demonstrated a comparable mouse iv PK profile to SNS-314.
Subject(s)
Antineoplastic Agents/chemistry , Benzimidazoles/chemistry , Protein Kinase Inhibitors/chemistry , Protein Serine-Threonine Kinases/antagonists & inhibitors , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacokinetics , Aurora Kinases , Benzimidazoles/chemical synthesis , Benzimidazoles/pharmacokinetics , Cell Line, Tumor , Humans , Mice , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/pharmacokinetics , Protein Serine-Threonine Kinases/metabolism , Structure-Activity RelationshipABSTRACT
Compound 1 (SNS-314) is a potent and selective Aurora kinase inhibitor that is currently in clinical trials in patients with advanced solid tumors. This communication describes the synthesis of prodrug derivatives of 1 with improved aqueous solubility profiles. In particular, phosphonooxymethyl-derived prodrug 2g has significantly enhanced solubility and is converted to the biologically active parent (1) following iv as well as po administration to rodents.