Interactions of heteroaromatic compounds with nucleic acids. 2. Influence of substituents on the base and sequence specificity of intercalating ligands.

摘要: This paper presents the results of a systematic study on effects substituents base and sequence specificity tricyclic heteroaromatic compounds interacting with DNA by intercalation. All tested are derived from proflavine acridine orange analogs different heteroatoms in middle ring. Their specificities were determined differential dialysis ligand against samples differing G · C content. The main indicate that (a) introduction phenyl substituent into one two available positions ring increases or decreases depending position where substitution takes place; (b) type neutral red (2-methyl-3-amino-7-dimethyl-amino-phenazine) show unexpectedly high (c) ligands pronounced for adjacent pairs can be constructed combining structural elements an additional residue same molecule. The further related to phenylated revealed improved destroyed substituents. The comparison DNA-affinity data studied leads suggestion arises mainly electronic factors which strongly controlled through steric constraints possible complex geometries. As basis discussion structure is considered extra at N-5 phenazinium system, protrudes large groove helix while part inserted between base-pairs.