M. M. Il’in

Redox-active ferrocene-modified pyrimidines and adenine as antitumor agents: structure, separation of enantiomers, and inhihibition of the DNA synthesis in tumor cells

The structures, electrochemical properties, enantiomeric separation of ferrocenyl-(alkyl)pyrimidines and ferrocenyl(ethyl)adenine and their effects on the DNA synthesis in tumor cells were studied. Enantiomeric mixtures were separated by HPLC on modified cellulose as the chiral selector. The electrochemical properties of compounds were studied by cyclic voltammetry. All compounds have reversible single-electron redox transition in the region of 0.52–0.60 V, which belongs to ferrocene—ferrocenium with a positive shift compared to ferrocene (0.52 V). The molecular structure of 1-N-(ferrocenylbenzyl)-5-iodocytosine was studied by X-ray diffraction. 1-N-(Ferrocenylethyl)adenine was studied for ability to inhibit the DNA synthesis in the human ovarian cancer cell culture by the 3H-thymidine test.

Laws of sorption of some aromatic heterocycles from solutions on nanoporous supercrosslinked polystyrene

Principles of the sorption of 5-tetrazole, 1,3,4-oxadiazole, and 1,2,4,5-tetrazine derivatives from solutions of various composition on nanoporous supercrosslinked polystyrene were studied by high performance liquid chromatography. The influence of the nature of heteroatom on the sorption of these heterocycles was demonstrated. The role of different types of intermolecular interactions in the sorption of the studied substances from solutions on nanoporous supercrosslinked polystyrene in quasi-normal phase and reverse phase liquid chromatography are discussed.

Thermodynamics of the sorption of 1,3,4-oxadiazole and 1,2,4,5-tetrazine derivatives from solutions on hypercrosslinked polystyrene

The sorption of a series of aromatic heterocycles on neutral hypercrosslinked polystyrene from maximally dilute acetonitrile and water.acetonitrile solutions of them is investigated by high-performance liquid chromatography in a range of column temperatures from 308 to 348 K at 5 K intervals. It is found that for all heterocycles, the logarithm of the retention factor versus the reciprocal of the temperature dependences can be approximated by linear functions with r2 ≥ 0.999. It is established that the true compensation effect (which does not result from the correlation between enthalpy and entropy determination errors) occurs during the sorption of heterocycles on hypercrosslinked polystyrene from both acetonitrile and water-acetonitrile solutions. It is shown that in the compensation diagram, the points corresponding to sorbates are grouped together according to the type of sorbate-sorbent interactions. It is found that changes in the Gibbs energy, enthalpy, and entropy of sorption from acetonitrile solutions and for sorption from water-acetonitrile solutions are related to one another by linear dependences.

Thermodynamics of adsorption of aromatic compounds from non-aqueous solutions by MIL-53(Al) metal-organic framework

The thermodynamics of adsorption of mono-, di-, and tricyclic aromatic compounds by MIL-53(Al) metal-organic framework from their solutions in MeCN, MeOH and n-C6H14–PriOH was studied for the first time. It was found that the adsorption of the test substances from solutions in MeCN and MeOH is characterized by positive values of enthalpy and entropy changes, and the adsorption from n-C6H14–PriOH medium is characterized by negative enthalpy and entropy changes. Upon adsorption by MIL-53(Al) framework from polar media, aromatic compounds were proposed to transfer from the liquid phase with a higher degree of association into the solvent medium with a lower degree of association, molecules of which are disordered due to the strong interaction with the hydrophobic walls of the framework pores. It was concluded that the driving force of adsorption by MIL-53(Al) from MeCN and MeOH is increase in entropy of the system, while the factor of adsorption from n-C6H14–PriOH medium is decrease in enthalpy of the adsorption system. The compensation effect in liquid-phase adsorption of aromatic compounds by MIL-53(Al) framework was discovered. The effect of the liquid phase nature on selectivity of adsorption from solutions onto investigated metal-organic framework was demonstrated.

Sorption of adamantane phenylamide derivatives on hyper-cross-linked polystyrene from water–acetonitrile eluents

Study of the main physicochemical features of the sorption of phenylamide adamantane derivatives on hyper-cross-linked polystyrene from water–acetonitrile solutions shows that both hydrophobic and electronic interactions make a large contribution to retention, especially for a chlorine-containing derivative in which there are π–p and π–d interactions between the outer-shell electrons of the chlorine atom in addition to π–π interactions between aromatic fragments of the sorbate and sorbent.

Selective adsorption of organic compounds from solutions on hyper-cross-linked polystyrenes with ultimate degrees of cross linking

The adsorption selectivities of a series of organic compounds from solutions on hyper-cross-linked polystyrene networks (HPNs) with ultimate degrees of cross linking were studied by high performance liquid chromatography (HPLC). The thermodynamic characteristics of adsorption (TCA) of substances under study from water–organic solutions on such HPNs in the Henry region were determined. The TCAs of organic compounds on the HPNs under study as a function of their molecular structures are discussed. It was established that the magnitude of the Gibbs energy change upon adsorption increases with increasing the number of π-electrons in the adsorbed molecules in a series of both aromatic hydrocarbons and their sulfurcontaining heterocyclic analogs. As an example, a model mixture of organic compounds was separated on HPNs by HPLC. It was shown that middle and heavy oil fractions can be fractionated on HPNs into the groups of mono-, di-, and tricyclic aromatic compounds.

Synthesis of N-ferrocenylalkylated pyrazole derivatives

Carbonyl derivatives of N-ferrocenyl alkyl pyrazoles were synthesized. The techniques of analytical separation of racemates of the synthesized compounds were developed. The structures of three compounds were determined by X-ray diffraction analysis.

Sorption of certain isatins on various sorbents under RP-HPLC conditions

The results from chromatographic analysis of biologically active isatin derivatives on hyper-crosslinked polystyrene (HCLPS) and silica gel modified by octadecyl groups (SilC18) are presented. The constants of distribution of sorbates between a mobile phase and the investigated sorbents (Kx) and the changes in the standard differential molar Gibbs energies of adsorption

Quasi-normal phase chromatography of nitrogen-containing adamantane derivatives

(Delta _a bar G^circ )

Synthesis and properties of N-ferrocenylalkylated pyrroles

are calculated, along with the chromatographic retention-physicochemical property of sorbate dependences. It is found that the equations describing these dependences have high forecasting ability with respect to the values of retention factors of the investigated sorbates.