[Synthesis of triads based on deuteroporphyrin IX, naphthoquinone, and aromatic amino acids]. / Sintez triad na osnove deiteroporfirina IX, naftokhinona i aromaticheskikh aminokislot.

Two triad systems were synthesized from deuteroporphyrin IX by tethering 1,4-naphthoquinone derivatives and aromatic amino acids to its propionic groups using the method of mixed anhydrides. Physicochemical characteristics of the triads were studied, and the pi-electron systems of their chromophores were shown to interact. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2002, vol. 28, no. 4; see also http://www.maik.ru.

Photophysical properties of carborane-containing derivatives of 5,10,15,20-tetra(p-aminophenyl)porphyrin.

Absorption, fluorescence emission, fluorescence excitation spectra and fluorescence decay kinetics of carborane derivatives of 5,10,15,20-tetra(p-aminophenyl)porphyrin have been investigated. Carborane derivatives are prepared by acylation of the amino groups of 5,10,15,20-tetra(p-aminophenyl)porphyrin by 9-carboranyl acetyl chloride. From the analysis of the absorption and fluorescence spectra, it is concluded that covalent linking of carborane molecules to the tetraphenylporphyrin molecule significantly changes the self-conjugated pi-system of the porphyrin macrocycle: positions of maxima of absorption and fluorescence spectra shift to the red region by 3-8 nm; the halfwidths of these bands are broadened by 2.5-5.0 nm; the relative intensity of the bands I-IV also changes. The fluorescence decay kinetics of the carborane derivatives are biexponential. According to the experimental data and model simulation, it is concluded that the intramolecular electron transfer proceeds from the porphyrin excited part of the molecule to carboranyls with a rate constant of 415 ps(-1) and efficiency of 0.16-0.8. Recombination of separated charges occurs within 1.4 ns.

[the synthesis of diporphyrin systems on the basis of tetraphenylporphyrin derivatives bridged with peptide spacers]. / Sintez diporfirinovykh sistem na osnove proizvodnykh tetrafenilporfinina, soedinennykh peptidnymi speiserami.

Diporphyrin systems based on tetraphenylporphyrin derivatives bridged with dipeptide or tripeptide spacers containing Gly and Phe residues were synthesized, and their physicochemical properties were studied.

[Effect of the structure of the prosthetic group on the catalytic properties of prostaglandin H synthetase]. / Izuchenie vliianiia struktury prosteticheskoi gruppy na kataliticheskie svoistva prostaglandin-H-sintetazy.

The effect of vinyl groups of protohemin IX on its cofactor properties with respect to prostaglandin H synthetase has been studied. It was shown that substitution of ethyl groups or a hydrogen for vinyl groups affects neither binding of the prosthetic group to the apoenzyme nor catalytic properties of holo-prostaglandin H synthetase. Replacement of vinyl groups with bulkier substituents (hydroxyethyl or acetyl groups) decreases holoenzyme stability and catalytic activity. By comparison of the cofactor properties of protoporphyrin and hematoporphyrin macrocycles with different central ions (Fe3+, Mn2+, 2H+ in the case of protoporphyrin, and Fe3+, Mg2+, Cd2+ and Cu2+ in the case of hematoporphyrin), the presence of Fe3+ ions was shown to be mandatory for prostaglandin H synthetase activity. It was demonstrated that the cofactor structure modifications do not affect the holo-prostaglandin H synthetase inactivation rate constant in a reaction.