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.

Relationships between the echinocytogenic and stomatocytogenic action, structure-modifying effect on the erythrocyte membranes, and the hemolytic activity of IKHFAN antioxidants and their hydrophobicity have been established. These dependences are non-monotonic: as the hydrophobicity parameter increases, the echinocytogenic, stomatocytogenic, and hemolytic activities first increase, pass through a maximum, and then decrease, while the microviscosity of erythrocyte membranes varies in the opposite manner. These results can be useful in developing approaches to the synthesis of hybrid biologically active compounds, including drugs with controlled and targeted delivery to the corresponding cell membrane structures.

The capacity of erythrocyte membranes for organic nonelectrolytes from different chemical groups of chemical compounds was studied by the spin probe method and scanning electron microscopy. Hydrophobic spin-labeled derivatives of gamma-carbolin and stearic acid and the screened phenol antioxidant fenozan-1 were used as nonelectrolytes. Based on the analysis of electron spin resonance spectra of the hydrophobic spin-labeled nonelectrolytes and electron micrographs of erythrocytes, differences in the capacity of distribution regions in the intramembrane space of the derivative of gamma-carbolin and fenozan-1, on the one hand, and the spin-labeled derivative of fatty acid, on the other hand, were found. The first group has at least two membrane distribution regions, whereas in the second case only one type of distribution was found. The influence of limited membrane capacity on the realization of biological activity of organic nonelectrolytes is discussed.

The effect of regulatory peptide thyrotropin-releasing hormone (TRH) on the structure of the plasma membrane and morphology of rat erythrocytes was studied using a spin probe and scanning electron microscopy. EPR spectra of the spin probe introduced in the intramembrane space demonstrate that TRH at 10(-7) and 10(-3) M induces structural changes in the erythrocyte membrane. Scanning electron microscopy showed that introduction of TRH at 10(-11), 10(-7), and 10(-3) M in the erythrocyte suspension increased the proportion of discocytes as compared to the control. This effect is due to TRH-induced cell transformation in discocytes. The obtained data suggest that TRH affects the membrane structure and the morphology of erythrocytes, changes the functional activity of these cells and, thus, indirectly influences the rate of the oxygen supply to tissue.

Scanning electron microscopy revealed changes in erythrocyte morphology induced by the synthetic antioxidant phenozan-1. Phenozan-1 at 10(-7)-10(-5) M acts as an echinocytogen. This effect of the antioxidant is, probably, due to its distribution in the external monolayer of the erythrocyte membrane and associated structural changes.

The influence of chlorine-containing pesticides, which are representatives of various classes of chemical compounds and possess various pesticidal activities, on the NAD . H oxidase activity of the submitochondrial particles (SMP) obtained from beef heart was studied. It was found that the strongest inhibitors of NAD . H oxidase of the SMP are chloro-derivatives of aromatic hydrocarbons (DDT and its analogs DDD and DDE). Derivatives of propionic and acetic acids (propinate, dalapon, MCAA, DCAA, and TCAA) did not exhibit any appreciable inhibiting effect under the experimental conditions. Criteria were introduced (phi and Ca50) permitting a quantitative characterization of the influence of pesticides on the respiratory chain of the mitochondria. Indications were obtained of possible mechanisms of the inhibiting action of the pesticides used.