Manifestation of intramolecular and intermolecular interactions in infrared absorption spectra of biologically active aminophenols

Abstract

529.1.047;543.42 FTIR methods were used to study intramolecular and intermolecular interactions in solutions and the solid state of the biologically active aminophenols 2-anilino-4,6-di-tert-butylphenol, N-(3,5-di-tert-butyl-2-methoxyphenyl)aniline, and 2,4-di-tert-butyl-10H-1-phenothiazinol. An analysis of the IR spectra has shown that intramolecular interactions between the OH and NH groups occur in solutions of aniline in CCl 4 are present in the non-associated state because of the absence of hydroxyl groups in the molecular structure. The OH and NH groups in solutions of 2,4-di-tert-butyl-10H-1-phenothiazinol in CCl 4 do not interact within the molecule due to a decrease in the conformational mobility of the molecular fragments due to the presence of the rigid C Ar -S-C Ar molecular bond in this compound. Intermolecular interactions involving the NH groups occur in the solid state of these compounds. Introduction. Derivatives of phenols and aromatic amines are widely used as stabilizers of industrial organic materials and preservatives of food products [1, 2]. Certain derivatives of diphenols [3, 4] and aminophenols [5, 6] have turned out to be effective regulators of radiation-induced reactions involving various types of organic radicals. It has been demonstrated [7] that the antioxidant properties of aminophenol (AP) derivatives are enhanced when the hydroxyls in the molecules are free and diminished when intramolecular H-bonds (IHB) of the O-H⋅⋅⋅N or O-H⋅⋅⋅O=C are formed.The aforementioned compounds have also been found to be highly effective in the treatment and cure of pathologies caused by disruptions in the antioxidant system of an organism [8]. AP derivatives are also currently used as antiviral agents to treat herpes infections [9][10][11].Thus, a multifaceted study of these compounds, which have a broad spectrum of functional properties, is interesting to chemistry, pharmacology, and medicine.Herein we present results of an IR spectroscopic study of intramolecular and intermolecular interactions (IaMI and IrMI) of the three structurally similar and biologically different AP derivatives 2-anilino-4,6-di-tert-butylphenol (henceforth AP I), N-(3,5-di-tert-butyl-2-methoxyphenyl)aniline (AP II), and 2,4-di-tert-butyl-10H-1-phenothiazinol (AP III).

Spectral-Luminescent Properties and Photolysis of Some Phenol Derivatives

“…Phenol and p-cresol are well-known antibacterial agents with wide spectrum of action, have anti-inflammatory properties, and act on gram-positive and gram-negative flora and fungal microorganisms; therefore, they are actively used as antibacterial additives to polymers [8,9]. The study of phenols by optical and quantum-chemical methods is urgent in connection with high pharmacological activity of these compounds [10][11][12][13].…”