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a sulfonamide fragment but also conformational equilibrium among these types of intramolecular interactions are essential for the manifestation of high efficiency in suppressing HIV-infection in cell culture.Introduction. Many derivatives of aminophenols (AP) are known to be effective antioxidants that are capable of changing the course of free-radical processes [1]. These compounds also have traditional applications as stabilizers of industrial organic materials and as food preservatives [2,3]. They exhibit high efficiency for prevention and treatment of pathologies due to disorders in the human antioxidant system [4] and as antiviral agents against herpes simplex and flu A virus [5][6][7][8][9]. AP derivatives that suppress HIV-infection in cell culture were recently synthesized [10].The pharmacological properties of AP are related to their effect on the course of free-radical processes in biological systems. Steady-state radiolysis and IR spectroscopic methods found that the antioxidant properties of AP are enhanced when the hydroxyls in the molecules are free and diminished upon forming various types of intramolecular hydrogen-bonds (IHB) [11]. As a rule, reactions involving active oxygen species occur nonselectively. Their occurrence in biological systems can damage both the cells themselves and viruses incorporated into them if highly active antioxidants are used.The question of which AP derivatives that are added to biological systems can change the course of free-radical reactions so that an effective and stable antiviral effect is obtained remains open. Therefore, it is important in principle to study properties of individual molecules such as the ability to form IHB because the type of IHB found in the AP is frequently related to their antiradical and antiviral activity [12,13].Herein IR-Fourier spectroscopy is used to study intramolecular interactions (IMI) in CCl 4 solutions of five structurally similar AP derivatives, 4,6-di-tert-butyl-2-(phenylamino)phenol (AP I), N-(3,5-di-tert-butyl-2-hydroxyphenyl)acetamide (AP II), N-(2-hydroxy-3,5-di-tert-butylphenyl)-4-methylbenzenesulfonamide (AP III), N-(2-methoxy-3,5-di-tert-butylphenyl)-4-methylbenzenesulfonamide (AP IV), and N-(2-hydroxy-3,5-di-tert-butylphenyl) methanesulfo-namide (AP V):

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Modern problems in the diagnosis of oncological pathologies using spectroscopic methods of analysis are considered. Fourier-transform IR spectroscopy methods are illustrated by investigation of tissues of breast, thyroid gland, stomach, kidney, lung, and skin excised during surgical intervention. IR spectra of surgical material are compared with data of histological analysis. Spectra of proteins and lipids in malignant neoplasms differ from those in benign tumors and in tissues beyond the pathological focus. Differences in protein spectra are attributed to changes in the supramolecular structure due to cleavage of intramolecular C=OH-N hydrogen bonds. Differences in IR spectra of lipids in neoplasms, when compared with those in normal tissues, are caused by changes in the structure of side chains of fatty-acid radicals appearing in malignant tumors. Spectral signatures of malignant pathology are revealed.Introduction. Timely detection of oncological pathology is of prime importance for selecting effective methods for treating oncological diseases. However, the diagnosis of malignant neoplasms is a very complicated aspect of oncology because tumors often manifest clinically as various symptoms, especially in early stages.The essence of the problem is that diagnostic methods currently used in medical practice such as visual, palpation, ultrasound, and x-ray, in addition to MRI and CT are capable in principle of detecting only a tumorous mass. The final conclusion about whether the detected pathology is benign or malignant is made based on morphological investigations. A correct diagnosis is possible only with careful adherence to procedures for obtaining and processing the material to be analyzed. Important considerations for a reliable diagnosis are subjective factors such as the special professional training and experience of the surgeon and a highly qualified pathologist.The morphological diagnosis of a tumor is established based on a whole set of signatures such as cytological characteristics, cell topography, their relationships to basal membranes, vessels, and the condition of the stroma, which acts as a mediator between neoplasms and the organism as a whole. Morphological signatures of malignancy are idiosyncratic to each organ and tissue and can vary considerably. Therefore, both clinical data and results of laboratory tests are very significant for a differential diagnosis of malignant tumors and elucidation of the factors stimulating malignant growth. Information about the tumor location, its growth rate, and the age of the patient can in several instances play a decisive role in the morphological diagnosis [1]. Nevertheless, available morphological data can in many cases be insufficient for an accurate verification of the pathological (tumor) process so that a conclusion about whether the tumor is benign or malignant is presumptuous in nature [2]. Because fundamental life processes, from single-celled organisms to man, are carried out on the molecular level, novel methods that investigate the pathology o...