S. N. Samovich

Effects of curcumin and related compounds on processes involving α-hydroxyethyl radicals.

Effects of curcumin and related compounds on product formation in radiolysis of aerated and deaerated ethanol were studied. Ab initio calculations of enthalpy values relating to O-H bond dissociation and H-atom addition to > C = O bonds of the compounds under study have been performed. The obtained data allowed the conclusion that the presence of a 7-carbon chain containing conjugated > C = C < and > C = O bonds in the structures of curcumin and its analogues makes these compounds capable of inhibiting the reactions involving α-hydroxyl-containing carbon-centered radicals. This finding broadens the existing views concerning radical-regulating properties of curcuminoids, and it should be taken into account when practical use of these compounds is envisaged.

Spectroscopic and proton-acceptor properties of biologically active molecules of benzoic acid and its derivatives

We have measured the absorption, fluorescence, fluorescence excitation spectra, fluorescence quantum yields, and IR Fourier-transform spectra of aromatic acids in solutions. We have considered spectroscopic particular features of benzoic acid, its hydroxylated and methoxylated derivatives. Using quantumchemistry methods, we have calculated and interpreted electronic spectra. Data of calculations have been compared with experimental results. We have ascertained the main channels and mechanisms of photophysical relaxation processes in the molecules under study. Proton-acceptor properties of molecules of aromatic acids have been evaluated. We have analyzed in detail mechanisms by which hydrogen bonds are formed, intramolecular charge redistribution is realized, and the electron density of oxygen atoms changes. Spectroscopic indications of participation of oxygen-containing groups in intramolecular interactions and in intermolecular interactions with the formation of cyclic dimers have been revealed.

Synthesis and Antiviral Activity of Hydroxy-Substituted Benzaldehydes and Related Compounds

A series of hydroxy-substituted benzaldehydes and related compounds were synthesized and studied in cell culture against herpes simplex type I (HSV-1) and influenza A (H7N1) viruses. It was found that salicylaldehyde, 2,3-dihydroxybenzaldehyde, and gossypol could suppress HSV-1 replication. The structure–activity relationship of the series of hydroxylated benzaldehydes was analyzed.

IR spectra of benzaldehyde and its derivatives in different aggregate states

We have measured the IR Fourier-transform spectra of biologically active benzaldehyde and its derivatives in the gas and liquid phases. For compounds of this class, the role played by C=O, OH, and CH groups in intra- and intermolecular has been analyzed. We have revealed spectral features that characterize the participation of C=O groups of unsubstituted benzaldehyde molecules in the occurrence of intermolecular hydrogen bonds C=O...H-C with the formation of molecular dimers of different types. For 2-hydroxybenzaldehyde molecules, spectral data have been obtained that are indicative of the occurrence of intramolecular hydrogen bonds of the C=O...H-C type in solutions. In 2-methoxybenzaldehyde molecules, no intramolecular hydrogen bonds have been observed.