[A microscopic model of complex formation of intercalators with DNA: analysis of NMR spectroscopy data].

A model of intercalation complex formation of ligands with an arbitrary oligonucleotide sequence has been proposed, which takes in the explicit form the microscopic constants and the parameters of the cooperativity of binding to particular sites of the oligomer into account. The model has been adapted for the analysis of NMR spectroscopy data.

[Interaction between aromatic antibiotics and vitamins: 1H NMR analysis of the heteroassociation of nicotinamide and anthracycline antitumor antibiotics].

The interaction between anthracycline antitumor antibiotics daunomycin and novatrone and the vitamin nicotinamide has been investigated by one- and two-dimensional 1H NMR spectroscopy (500 MHz). Due to significant differences in structures of the chromophores of interacting molecules, a two-site heteroassociation model has been developed, allowing the arrangement of one and two nicotinamide molecules on the chromophore of the antibiotic. The equilibrium association constant, thermodynamical parameters (deltaH, deltaS) of the heteroassociation of nicotinamide with daunomycin and novatrone and the induced proton chemical shifts in the heterocomplexes have been determined from the concentration and temperature dependences of proton chemical shifts of interacting molecules.

[A structural and thermodynamic analysis of novatrone and flavin mononucleotide heteroassociation in aqueous solution by 1H NMR spectroscopy].

A heteroassociation of antitumor antibiotic novatrone (NOV) and flavin mononucleotide (FMN) in aqueous solution was studied by one- and two-dimentional 1H NMR spectroscopy (500 MHz) to elucidate the molecular mechanism of the possible combined action of the antibiotic and vitamin. The equilibrium reaction constants, induced proton chemical shifts, and the thermodynamic parameters (deltaH and deltaS) of the NOV and FMN heteroassociation were determined from the concentration and temperature dependences of proton chemical shifts of the aromatic molecules. The most favorable structure of the 1 : 1 NOV-FMN complex was determined by both the method of molecular mechanics (X-PLOR software) and the induced proton chemical shifts of the molecules.

[1H NMR analysis of the complex formation of aromatic molecules of antibiotic and vitamin in aqueous solution: heteroassociation of actinomycin D and flavin mononucleotide].

The molecular mechanism of the combined action of antibiotic and vitamin was studied by NMR spectroscopy. The heteroassociation of the antitumor antibiotic actinomycin D and flavin mononucleotide was investigated as a function of concentration and temperature by 500 MHz 1H NMR spectroscopy. The equilibrium association constant, the thermodynamic parameters (deltaH, deltaS) of heteroassociation of actinomycin D with flavin mononucleotide, and the limiting values of proton chemical shifts in the heterocomplex were determined from the concentration and temperature dependences of proton chemical shifts of molecules.