PHOTOREACTIVE ETHIDIUM AND AZIDOETHIDIUM DYES - SYNTHESIS, PROPERTIESAND COVALENT BINDING TO OLIGODEOXYNUCLEOTIDES

Methods of synthesis of ethidium and azidoethidium dyes, containing th e primary aliphatic amino group of the 3-aminopropionic acid residue w ere developed. The derivatives were characterized by spectral methods (NMR, UV- and fluorescent spectroscopy). Complex formation of ethidium dyes with DNA was studied by fluorescent technique. The stoichiometry of the dye - DNA complex was 1 : 4 (dye to base pair) for all the der ivatives. Photoreactivity of azidoethidium dyes was 10(3) times higher and the quantum yield of the photoproducts was 10(5) times higher tha n those for ethidium dyes. A method of preparation of 5'-phosphoramide photoreactive oligodeoxynucleotide derivatives was suggested, with et hidium derivative of heptanucleotide pd(CCAAACA) as an example.