Synthesis and structure of dihydroberberine nitroaryl derivatives – potential ligands for G-quadruplexes

A method was developed for the synthesis of dihydroberberine nitroaryl derivatives on the basis of dihydroberberine reactions with aromatic electrophiles (picryl chloride, 4-chloro-7-nitrobenzofurazan, 4-chloro-5,7-dinitrobenzofurazan, and 7-chloro-4,6-dinitrobenzofuroxan). The obtained 13-substituted dihydroberberine derivatives represent structures with significant intramolecular charge transfer and, according to the results of molecular docking analysis, can effectively bind with G-quadruplexes of telomeric DNA fragments.