The interactions of the drugs 2,7-bis[(diethylamino)-ethoxy]-fluoren-9-one dihydrochloride (Tilorone), 2,7-bis[(dipropylamino)-acetamido]-fluoren-9-one dihydrochloride (FA-2), 2'-(4-hydroxyphenyl)-5-(4-methyl-1-piperazinyl)-2,5'-bi-1H-benzimidazole trihydrochloride (Hoechst 33258), and hematoporphyrin IX derivative (HPD) with synthetic self-complementary DNA (36-b.p.; 5'-biotin-spacer-[d(CGCTATATAGCG)]3-3') were studied by SPR (Surface Plasmon Resonance). Monolayers of biotinylated DNA were immobilized on a streptavidin-dextran-gold triple-layer. Small portions of the drugs (approximately 30 pmol/ml) were injected in continuous flow. The mass corresponded to the amount of the bound molecules. Injections of 50 mM sodium hydroxide pulses separated the DNA double strands, releasing the effector molecules. Subsequent treatments with the effectors gave reproducible results. The maximum interaction between drug and DNA was observed in the case of Tilorone. 41 molecules could bind to the 36-b.p. DNA duplex. To investigate the microscopic behavior in condensed nucleic acid phases, SFM (Scanning Force Microscopy)-imaging and polarizing microscopic observations of DNA-effector complexes were carried out. Supplementary UV-absorption thermal denaturation curves of DNA with the above-mentioned effectors in dilute solutions were measured. As an additional aid to understand the geometries of DNA-drug interactions, computer simulations were performed and compared with the experimental data.

ABSTRACT:The synthesis of dark brown poly(2,5-furan-diylvinylene) (1) via aldol condensation reaction of 5-methylfuran-2-carbaldehyde as an one pot reaction yields an organic semiconductor which has long-lasting stability in the presence of air and water (tested over 10 years). Decolorization (decomposition) was observed only under long-time illumination. The reaction products were characterized by IR-, 1 H NMR-, mass-spectrometry and elemental analysis. Polymer 1 can be oxidized (doped) with Lewis acids such as iodine, AsF 5 and FeCl 3 . The values of the electrical conductivity range from 10-8

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