title: Synthesis of small molecules targeting multiple DNA structures using click chemistry.
abstract: The ability of small molecules to target DNA forms the basis of many clinically used antitumour agents. This study examines the effects of novel 9-aminoacridine carboxamides, synthesised by click chemistry based upon the reactions of either 9-(2-azidoethyl)amino or 9-propargylaminoacridine compounds, on various types of DNA tertiary structures. This gave either monomeric or dimeric compounds, the dimeric derivatives being the first unsymmetrical acridine dimers to be described. The compounds were assayed for duplex DNA, quadruplex DNA and four-way junction DNA binding. Their antiproliferative activity in the Human promyelocytic leukaemia cell line, HL60, was also assessed. Although for some of the compounds, notably the acridine 4-carboxamides, activity correlated with DNA binding affinity, for others it did not, with the rigidly linked dimers in particular showing a complicated relationship between 3- and 4-carboxamide structure and biological activity. The monomeric 3-carboxamides were more effective at stabilising G-quadruplex structures and also gave more hits in the four-way junction stabilisation assay. There is clear evidence from the binding of the 3-carboxamides that these compounds destabilise the open X form of the junction at lower concentrations and stabilise the X-stacked at higher concentrations. This might have implications for the biological activity of these compounds against proteins that bind to the Holliday junction (HJ).
authors.affiliation: School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich, UK.
authors.forename: Lesley A
authors.initials: LA
authors.lastname: Howell
authors.forename: Richard A
authors.initials: RA
authors.lastname: Bowater
authors.forename: Maria A
authors.initials: MA
authors.lastname: O'Connell
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Reszka
authors.forename: Stephen
authors.initials: S
authors.lastname: Neidle
authors.forename: Mark
authors.initials: M
authors.lastname: Searcey
mesh_terms: D000609:Aminoacridines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D045744:Cell Line, Tumor; D057930:Click Chemistry; D004247:DNA / Q000737:chemistry* / Q000187:drug effects; D016503:Drug Delivery Systems; D004354:Drug Screening Assays, Antitumor; D005260:Female; D006801:Humans; D007938:Leukemia / Q000188:drug therapy; D046911:Macromolecular Substances; D008968:Molecular Conformation; D054852:Small Molecule Libraries / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000609:Aminoacridines; D000970:Antineoplastic Agents; D046911:Macromolecular Substances; D054852:Small Molecule Libraries; C054505:9-aminoacridine-4-carboxamide; D004247:DNA