Hybrid Antioxidants

The term of hybrid antioxidants implies molecules whose strueture contains parts responsible for antioxidant properties and fragments of moleeules responsible for other specifie funetions. 

The largest group of antitumor eompounds ineludes nitroxyl derivatives of anthracycline antibioties. One of the major aehievements of the chemistry and biochemistry of hybride antioxidants of this elass is the development of emoxypin (ruboxyl) - a nitroxyl derivative of the anthraeyeline antibiotic - rubomycin. 

Hence, a hybrid molecule - an analog of acetylcholine [CH3C00CH2CH2N (CH3)30H ] was constructed. In this molecule, instead of acetic acid, the ester bond is formed by carboxylic acids that contain a 2.6-di-tert.butyl-4-hydrophenyl fragment. We called these hybrid antioxidants ichfans. 

Effect of Acyl Donor Nature Synthesis of Hybrid Antioxidants... 

In addition to free fatly acids and their esters as previously described, compounds with antioxidant potency were also used as acyl donors. In order to investigate the synthesis of hybrid antioxidants, the enzymatic acylation of escuhn catalyzed by immobilized CALB in the ionic liquids [bmtm]BF4 and [bmim]PF6 was investigated using several phenolic acids as well as their corresponding vinyl esters. 

As can be seen in Figure 9.4, the enzymatic synthesis of hybrid antioxidants of esculin is feasible in ionic Hquids, resulting in good conversion yields. The conversion yields obtained were higher in ionic liquid [bmim]PF6 as compared to [bmim]BF4 for all phenohc acids tested, while the use of phenohc acid esters in transesterification reactions led to higher conversion yields in both ionic hquid media used. 

Stabilization of Cell Membranes by Hybrid Antioxidants in Therapy of Neurodegenerative Diseases... 

A hybrid antioxidant of new generation - ichfan is suggested for the therapy of membrane-pathologies associated with neurodegenerative diseases. It was shown that the compound applied in a wide range of concentrations modifies the properties of erythrocyte membranes and cells of Ehrlich ascitic carcinoma and changes the functional state of cells. Incorporated in the lipid phase and near-protein lipids of membranes, the antioxidant affects the structural state of the lipid bilayer, the structure and functional activity of proteins, in particular, the functions of ionic channels. Recommendations were made as to the compound doses responsible for the pronounced antioxidant and stabilizing effects and the absence of unfavorable side-effects. 

Thus, the discovered stabilizing efficiency of hybrid antioxidant ichfan on cell membranes with regard to its pronounced antioxidizing effect and feasibility of permeation through the hematoencephalic barrier may be of primary importance for the membrane therapy of neurodegenerative diseases. 

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