title: Synthesis and DNA binding properties of novel benzo[b]isoquino[2,3-h]-naphthyridines.
abstract: Several benzo[b]isoquino[2,3-h]-naphthyridines have been prepared via formal hetero-Diels Alder reaction of N-aryl imines as a key step. These compounds have different side chains at C-11, and a cis or trans configuration at the C-8a,C-14a ring junction. Binding constants for the interaction with oligonucleotides and polynucleotides were determined by UV absorption and melting experiments. NMR experiments (NOE) revealed that the cis isomers, showing a slightly folded structure, preferentially bind to the minor groove of AT-rich oligomers. In contrast, the trans isomers prefer the CG-rich sequences, leading to cap-complexes with the isoquinoline moiety stacked at the top of the double helix, in agreement with the flatter shape, and with a preference for the 3'-terminals, as found for camptothecins. Models of the complexes were built up by molecular dynamics (MD) calculations, by using the inter-proton distances derived from the NOE values. Cytotoxicity assays against human Ewing sarcoma cell lines RD-ES and CAD-ES1 were performed.
authors: Institut für Organische Chemie, Technische Universität Braunschweig, Hagenring 30, D-38106 Braunschweig, Germany.
authors: Oliver
authors: O
authors: Koepler
authors: Stefania
authors: S
authors: Mazzini
authors: Maria Cristina
authors: MC
authors: Bellucci
authors: Rosanna
authors: R
authors: Mondelli
authors: Angelika
authors: A
authors: Baro
authors: Sabine
authors: S
authors: Laschat
authors: Marc
authors: M
authors: Hotfilder
authors: Christophle
authors: C
authors: Viseur
authors: Wolfgang
authors: W
authors: Frey
mesh_terms: D045744:Cell Line, Tumor; D004247:DNA / Q000737:chemistry*; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D008958:Models, Molecular; D009287:Naphthyridines / Q000138:chemical synthesis* / Q000737:chemistry* / Q000494:pharmacology; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D009287:Naphthyridines; D004247:DNA