Thermostimulated structural changes in C60-CCl4 and C70-CCl4 crystal solvates

The crystal solvates in C₆₀-CCl₄ and C₇₀-CCl₄ systems obtained by crystallization from CCl₄ solution at room temperature were studied by IR Fourier spectroscopy and X-ray diffraction. The C₇₀ · (CCl₄) _n crystal solvate was obtained and studied for the first time; its hexagonal crystal lattice has unit cell parameters a = 10.658 ± 0.001 Å and c = 10.811 ± 0.002 Å. The temperature ranges of its destruction were determined.     

Design and development of macrocyclization methods for compounds with potential tuberculocidal activity to decrease CYP450 liver cytochrome inhibition

A procedure for macrocyclization of compounds with potential tuberculocidal activity was developed in order to obtaining compounds with a lower degree of inhibition of the key CYP 3A4 cytochrome.     

Oxidation of C60 and C70 fullerites in air

The oxidation of C₆₀ and C₇₀ fullerites and C₆₀/C₇₀ mixture is accompanied by the decomposition of the carbon frameworks of the molecules at annealing temperatures of 250 and 445°C. Fourier-IR and HPLC studies show that the oxidation/decomposition of C₇₀ molecules is more active than that of C₆₀. The stages of fullerite interaction with oxygen while heating in air were determined.     

Polynomial neural network for linear and non-linear model selection in quantitative-structure activity relationship studies on the internet

This article presents a self-organising multilayered iterative algorithm that provides linear and non-linear polynomial regression models thus allowing the user to control the number and the power of the terms in the models. The accuracy of the algorithm is compared to the partial least squares (PLS) algorithm using fourteen data sets in quantitative-structure activity relationship studies. The calculated data show that the proposed method is able to select simple models characterized by a high prediction ability and thus provides a considerable interest in quantitative-structure activity relationship studies. The software is developed using client-server protocol (Java and C++ languages) and is available for world-wide users on the Web site of the authors.     

A new method for [c,d]pyridine peri-annelation: synthesis of azapyrenes from phenalenes and their dihydro derivatives

An effective synthesis of various azapyrenes from phenalenes and their dihydro derivatives has been developed using 1,3,5-triazines in polyphosphoric acid (PPA).     

Photocatalytic properties and structure of chitosan-based porphyrin-containing systems

The photocatalytic activity of the disodium salt of substituted hematoporphyrin in a model reaction of tryptophan oxidation in the presence of chitosan with different molecular masses and a block copolymer of ethylene and propylene oxides (Pluronic F-127) is studied. It is shown that, in the presence of the Pluronic, the catalytic activity of the chitosan-porphyrin system increases. The structure of chitosan-Pluronic systems, depending on the molecular mass of chitosan and the presence of porphyrin, is examined by AFM. A pleasible mechanism of the influence of the Pluronic on the photocatalytic activity of chitosan-por-phyrin systems is proposed.