The apoptotic effect of the antioxidant anphen sodium, a spatially hindered phenol, which has antitumor activity—in particular, inhibiting the development of tumor cells in sarcoma—has been studied. It was found that the administration of anphen sodium (10 –4 M) into a cell culture of Lewis carcinoma of mice already after 1–1.5 h led to the exposure of phosphatidylserine and the beginning of the process of apoptosis in the cells (according to the fluorescence of annexin V-FITC). With the combined action of H 2 O 2 (5 μM) and anphen sodium, the permeability of cells to acridine orange increased, and the number of apoptotic cells also increased to 80–100%. The formation of both single and numerous apoptotic bodies inside the cell was observed in tumor cells. Under the same conditions, a smaller number of apoptotic cells (14–16%) were found in spleen cells (splenocytes) of healthy mice, probably due to the action on only cells ready for apoptosis. Previously, we discovered the effect of anphen sodium on antiapoptotic proteins of the Bcl-2 family and hypothesized that this compound leads to apoptosis by the mitochondrial pathway. Since H 2 O 2 at low concentrations can act as a secondary messenger and stimulate the external pathway of apoptosis, it is supposed that the joint action of H 2 O 2 and anphen sodium leads to increased apoptosis by activating the mitochondrial and extrinsic signaling pathways.

It was shown by immunoblotting that the introduction of an antitumor antioxidant, sodium 2-carboxy-2-( N -acetylamino)-3-(3,5-di- tert -butyl-4-hydrophenyl)propanoate (anphen sodium), into a suspension of Lewis carcinoma cells induces a sharp decrease in the contents of the monomer and homodimer of the anti-apoptotic Bcl-2 protein. According to fluorescence analysis, the number of apoptotic cells sharply increased 1 h after exposure to anphen sodium; preliminary addition of 5 μmol L -1 of hydrogen peroxide increased the cell membrane permeability of anphen sodium and the number of apoptotic cells. The onset of apoptosis detected using fluorophores is comparable in time with the start of the decline of the Bcl-2 level. It was assumed that the mechanism of action of anphen sodium may include the interaction of the agent with the hydrophobic (BH3) domain of Bcl-2 family proteins.

The effect of new synthetic antioxidants, anphens, on erythrocyte morphology was studied. Insignificant cell transformations induced by the hydrophilic derivative of anphen-1 into echinocytes, as well as cell transformations into stomatocytes under the action of hydrophobic derivatives of anphens-2, 3, and 4 were revealed. The data we obtained indicate the intercalation of these compounds into the erythrocyte membrane. The distribution of compounds in the intra-membrane space depends on their hydrophobicity. A hydrophilic compound, anphen-1, is predominantly located in the outer monolayer of the membrane, while hydrophobic derivatives occur in the inner monolayer. It is proposed that the biological activities of anphen-3 and anphen-4 can occur in both monolayers as they move through the membrane, while the hydrophilic compound, anphen-1, exerts an insignificant membranotropic effect and can act only in the outer monolayer of the membrane. Variability in the efficiency of the concentration-dependent modifying action of the compounds with different hydrophobic properties has been found.

Sodium (1) and potassium (2) 1-(carboxy)-1-(N-methylamide)-2-(3′,5′-di-tert-butyl)-4-hydroxyphenyl)-propionates form crystal hydrates, which exist as both monomers and dimers. Quantum-chemical calculations in the PM6 approximation are used to determined the enthalpies of formation −H f po , thermal enthalpy H po, and entropy S po of the monomers and dimers, which are indicative of the possibility of existence of the dimers of propionates of alkali metals. The biological activity of these compounds in animal and plants is demonstrated to be dependent on their concentrations. Compounds 1 and 2 turned out to be efficient in the treatment of burn injuries, cancer, and radiation damage (in vivo and in vitro), as well as in promoting the growth of cereal plants.

Thionyl chloride is a reagent, which reacts with amino acid acetyl derivatives to yield corresponding acyl chlo rides. However, a reaction of 2 (acetylamino) 3 [3 ,5 di(tert butyl) 4 hydroxyphenyl]propanoic acid (1) in so lution of thionyl chloride gave 3,3 ,5,5 tetra(tert butyl) 4,4 dihydroxybiphenyl (2) and 3,3 ,5,5 tetra(tert butyl) diphenoquinone (3), rather than expected 2 (acetyl amino) 3 [3 ,5 di(tert butyl) 4 hydroxyphenyl]prop anoyl chloride (Scheme 1). Formation of compounds 2 and 3 is usually observed under conditions of the oxidative condensation of 2,6 di(tert butyl)phenol and its certain derivatives.1—4 Therefore, it can be suggested that the for mation of compounds 2 and 3 in the reaction of acid 1 with thionyl chloride involves a red ox process.

In the reaction esterification 2(N-acetylamid)-3(3 ’, 5 '-di-tert.butyl-4 '-hydroxyphenyl) propionic acid by alcohols (MeOH, Et ОН, isoPrOH, n-BuOH, n-C 9H 17OH) in the presence of SOCl 2 5 antioxidants with yields of 90-94 % are synthesised. Antioxidative properties of compounds on value к 7 at level 2.10 6 l.mol -1.s -1 that above, than for methyl ester (3 ’, 5 '-di-tert.butyl-4 '-hydroxyphenyll) propionic acid ( к 7 =2.10 4 l.mol -1.s -1). Are executed quantovo-chemical calculations of structure of methyl ester 2-(N-acetylamid)-3-(3 ’, 5 '-di-tert.butyl-4 '-hydroxyphenyl) propionic aci d which explain communication of entropy and structure with antioxidative properties.

Alkaline hydrolysis of diethyl N-acetylamino(3,5-di-tert-butyl-4-hydroxybenzyl) malonate is accompanied by decarboxylation. The efficiency of this process depends on the temperature and ratio of the reactants. A possibility of tautomerism with migration of the proton of phenolic hydroxyl and the influence of the structure on the antioxidation properties were considered on the basis of analysis of the IR spectral data and quantum chemical (PM6) calculation of the structures. The energies of homolysis of the OH bond of phenolic hydroxyl were calculated for a series of the synthesized compounds. It is proposed to predict the antioxidation activity on the basis of these values.

The transesterification of methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate with tetrakis(hydroxymethyl)methane depends on the equilibrium constants of the reversible reactions; for the final step, the equilibrium constant is K ≪ 1. The molecular geometries and the enthalpies and entropies of the equilibrium reactions were calculated by the semiempirical PM6 quantum chemical method. The thermodynamic equilibrium constants of the reversible reactions were calculated by the Boltzmann equation from the Gibbs energies G f ○. For tris-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoyloxymethyl](hydroxymethyl)methane, the dipole moment is μ = 0.97 D and the energy of the O-H homolysis is D OH = 347.3 kJ mol−1. For tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoyloxymethyl]methane, μ is 5.6 D and D OH is 321 kJ mol−1. The geometry of the structure affects the H-O homolysis energy and the chain termination coefficient under the conditions of inhibited cumene oxidation.

The energies of formation, enthalpies, and entropies of the conformers of 1-(carboxy)-1-(N-methylamide)-2-(3′,5′-di-tert-butyl)-4-hydroxyphenyl)-propionic acid and sodium and potassium 1-(carboxy)-1-(N-methylamide)-2-(3′,5′-di-tert-butyl)-4-hydroxyphenyl)-propionates are calculated by quantum-chemical methods in the PM6 approximation. A doubling of signals in the 1H NMR spectrum of the first conformer is observed, which merge into singlets when the compound is heated. Changes in the structure of the conformers and donor-acceptor complexes (solvates) occur with the preservation of the metal-ligand coordination bond. Calculations of the characteristics of 1-(carboxy)-1-(N-methylamide)-2-(3′,5′-di-tert-butyl)-4-hydroxyphenyl)-propionic acid and sodium and potassium 1-(carboxy)-1-(N-methylamide)-2-(3′,5′-di-tert-butyl)-4-hydroxyphenyl)-propionates in the PM6 approximation make it possible to predict the structure and properties of the solvated structures. The energies of homolysis of the H-O bond D (OH) are calculated, and a linear dependence of the antioxidant activity on D (OH) for the structures of the studied compounds is demonstrated. The results make it possible to predict the properties of antioxidants in the biological environment.

The determining factor of the reaction of 2,6-di-tert-butylphenol with alkaline metal hydroxides is temperature, depending on which two types of potassium or sodium 2,6-di-tert-butyl phenoxides are formed with different catalytic activity in the alkylation of 2,6-di-tert-butylphenol with methyl acrylate. More active forms of 2,6-(Bu2C6H3OK)-C-t or 2,6-(Bu2C6H3ONa)-C-t are synthesized at temperatures higher than 433 K and represent predominantly monomers of 2,6-di-tert-butyl phenoxides producing dimers on cooling.

The kinetics of catalytic alkylation of 2,6-di-tert-butylphenol (ArOH) with methyl acrylate (MA) in the presence of potassium 2,6-di-tert-butylphenoxide (ArOK) depends on the method for the preparation of ArOK. The reaction of ArOH with KOH at temperatures > 453 K affords monomeric ArOK, which properties differ from those in the case of potassium 2,6-di-tert-butylphenoxide synthesized by the earlier methods. The regularities of ArOH alkylation depend on the ArOK concentration, the ArOH:MA ratio, and the effect of microadditives of polar solvents.

The crucial factor of the reaction of 2,6-di-tert-butylphenol with alkali hydroxides is temperature, depending on which two types of potassium or sodium 2,6-di-tert-butylphenoxides are formed. These types exhibit different catalytic activity in the alkylation of 2,6-di-tert-butylphenol with methyl acrylate. More active forms of 2,6-But2C6H3OK or 2,6-But2C6H3ONa are synthesized at temperatures higher than 160 °C and are predominantly the monomers, which dimerize on cooling. The data of 1H NMR, electronic, and IR spectra for the corresponding forms of 2,6-But2C6H3OK and 2,6-But2C6H3ONa isolated in the individual state are in agreement with cyclohexadienone structure. In DMSO or DMF, the dimeric forms of 2,6-di-tert-butylphenoxides react with methyl acrylate to form methyl 3-(4-hydroxy-3,5-di-tert-butylphenyl)propionate in 64–92% yield.

The nature of the cation (K or Na) in 2,6-di-tert-pentylphenolates (ArOK or ArONa) affects the kinetics of the reaction of 2,6-di-tert-pentylphenol (ArOH) with methyl acrylate. This is associated with the ability of ArONa to replace the cation with a proton during interaction with methyl 3-(4-hydroxy-3,5-di-tert-pentylphenyl)propionate (HOArAlkOMe) to form a more efficient catalyst, sodium 4-(2-methoxycarbonylethyl)-2,6-di-tert-pentylphenolate (NaOArAlkOMe). Two different kinetic schemes, which describe the kinetics of the consumption of ArOH in the presence of ArOK and ArONa, are proposed. The elemental-stage rate constants are calculated by mathematical simulation of the reaction kinetics with consideration of the features of catalysis in the presence of ArOK and ArONa.

A kinetic scheme of the reaction between 6-tert-butyl-2-methylphenol and methyl acrylate in the presence of an alkali metal phenoxide has been proposed. The rate constants of the elementary steps describing the catalytic mechanism have been calculated. The reaction gives methyl 3-(5-tert-butyl-4-hydroxy-3-methylphenyl)propionate as the only product (Calkylation). The nature of the metal cation does not affect the reaction mechanism.