[DNA-intercalating compounds. Synthesis of several monomers and 1 dimer of phenanthridinium bearing aminoalkoylated chains].

Several monomeric phenanthridinium salts quaternarized in the 5 position by different aminoalkyl chains are prepared from ammoniac or diamines and 3,8-biscarbethoxyamnio (3-bromo)-5 propyl 6-phenyl phenanthridinium bromide I. The reaction between one of the monomeric salts and I leads, after deprotection of the amino-groups to the dimer: (4,7-diaza decamethylene) bis 5,5' (3,8-diamino-6 phenyl phenanthridinium) tetrachloride. All these compounds show the fluorescence properties of the phenanthridinium ring and exhibit DNA affinity constant higher than ethidium bromide.