title: An improved high yield total synthesis and cytotoxicity study of the marine alkaloid neoamphimedine: an ATP-competitive inhibitor of topoisomerase IIα and potent anticancer agent.
abstract: Recently, we characterized neoamphimedine (neo) as an ATP-competitive inhibitor of the ATPase domain of human Topoisomerase IIα. Thus far, neo is the only pyridoacridine with this mechanism of action. One limiting factor in the development of neo as a therapeutic agent has been access to sufficient amounts of material for biological testing. Although there are two reported syntheses of neo, both require 12 steps with low overall yields (≤6%). In this article, we report an improved total synthesis of neo achieved in 10 steps with a 25% overall yield. In addition, we report an expanded cytotoxicity study using a panel of human cancer cell lines, including: breast, colorectal, lung, and leukemia. Neo displays potent cytotoxicity (nM IC50 values) in all, with significant potency against colorectal cancer (lowest IC50 = 6 nM). We show that neo is cytotoxic not cytostatic, and that neo exerts cytotoxicity by inducing G2-M cell cycle arrest and apoptosis.
authors.affiliation: Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA. Linfeng.2.Li@ucdenver.edu.
authors.forename: Linfeng
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA. Adedoyin.Abraham@ucdenver.edu.
authors.forename: Adedoyin D
authors.initials: AD
authors.lastname: Abraham
authors.affiliation: Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA. Qiong.Zhou@ucdenver.edu.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Zhou
authors.affiliation: Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA. Hadi.Ali@ucdenver.edu.
authors.forename: Hadi
authors.initials: H
authors.lastname: Ali
authors.affiliation: Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA. Jeremy.OBrien@ucdenver.edu.
authors.forename: Jeremy V
authors.initials: JV
authors.lastname: O'Brien
authors.affiliation: Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA. Brayden.Hamill@ucdenver.edu.
authors.forename: Brayden D
authors.initials: BD
authors.lastname: Hamill
authors.affiliation: Division of Medical Oncology, School of Medicine, The University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA. John.Arcaroli@ucdenver.edu.
authors.forename: John J
authors.initials: JJ
authors.lastname: Arcaroli
authors.affiliation: Division of Medical Oncology, School of Medicine, The University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA. Wells.Messersmith@ucdenver.edu.
authors.forename: Wells A
authors.initials: WA
authors.lastname: Messersmith
authors.affiliation: Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA. Daniel.LaBarbera@ucdenver.edu.
authors.forename: Daniel V
authors.initials: DV
authors.lastname: LaBarbera
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000166:Acridines / Q000138:chemical synthesis* / Q000494:pharmacology*; D000951:Antigens, Neoplasm / Q000187:drug effects / Q000378:metabolism; D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D004250:DNA Topoisomerases, Type II / Q000187:drug effects / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000187:drug effects / Q000378:metabolism; D016195:G2 Phase / Q000187:drug effects; D006801:Humans; D008958:Models, Molecular; D012235:Rhodamines / Q000737:chemistry; D059005:Topoisomerase II Inhibitors / Q000138:chemical synthesis* / Q000494:pharmacology*
chemical_list: D000166:Acridines; D000951:Antigens, Neoplasm; D000970:Antineoplastic Agents; D004268:DNA-Binding Proteins; D012235:Rhodamines; D059005:Topoisomerase II Inhibitors; C474173:neoamphimedine; C022027:lissamine rhodamine B; D000135:Acid Phosphatase; D004250:DNA Topoisomerases, Type II