DNA Binding of an Organic dppz-Based Intercalator

Abstract

An improved synthesis of a water-soluble derivative of dipyrido[3,2-a:2',3'-c]phenazine (dppz) is reported. The structures of both dppz and the cation ethylene-bipyridyldiylium-phenazine dinitrate [[1][(PF(6))(2)]] have been obtained via X-ray crystallography. Metal complex derivatives of dppz are very well studied. However, using the water soluble [1][(NO(3))(2)], the nature of the interaction of a simple dppz unit with duplex DNA has been investigated for the first time. In both organic solvents and water, 1 displays unstructured luminescence, assigned to an intramolecular charge transfer. The emission is quenched on binding to natural and synthetic duplex DNA, including poly(dA).poly(dT). A variety of techniques reveal that the cation binds to DNA with an affinity comparable to those of many metal dppz complexes, via an intercalative binding mode.

Photoactive RuII–Polypyridyl Complexes that Display Sequence Selectivity and High‐Affinity Binding to Duplex DNA through Groove Binding

“…[17] Usually, DNA-induced decreases in luminescence indicate quenching of the excited state through photooxidation processes that involve nucleobases-commonly G sites. [18] However, this process can be discounted because it would require a further decrease in emission at higher [DNA]/A C H T U N G T R E N N U N G [complex] ratios, not an increase, as is observed.…”

Binary and ternary new water soluble copper(II) complexes of l -tyrosine and substituted 1,10-phenanthrolines: Effect of substitution on DNA interactions and cytotoxicities

“…The solid that remained was dissolved in water (50 mL), and filtered to remove any remaining solid. A 3:1 mole equivalent of ammonium hexafluorophosphate was added to the aqueous filtrate and the precipitate was collected, washed with cold EtOH and finally dried on air [42]. dq-nphen: Yield: 0.076 g, 28%.…”

Studies on the interaction of extended terpyridyl and triazine metal complexes with DNA

“…All solutions were in a Tris buffer (5 mM Tris and 25 mM NaCl) at pH 7. UV-vis and luminescent titrations were carried out using previously outlined procedures [21].…”