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The reaction of berberine derivatives containing at the O-9 position N,N-disubstituted acetamide fragments with sodium borohydride in methanol at 0 °C leads to a mild reduction of the "C" cycle with the formation of corresponding tetrahydroberberine derivatives with moderate to good yields. [ABSTRACT FROM AUTHOR]

Using modern technical means, which give information about the functional state of an athlete’s organism, can significantly increase the effectiveness of the training process control. Among such devices specialized hardware-software complex “Omegа-С” is often used. The aim of the pedagogical experiment was the effectiveness substantiation of using functional diagnostics opportunities during the training process of young biathletes. 15-16 year-old biathletes were divided into two identical according to physical readiness groups. The control group trained according to typical biathlon training program with earlier planned loads. In the experimental group the volume and intensity of the training loads were selected individually and were oriented toward functional state indices of an athlete’s organism at the moment, which precedes the beginning of the work. Modern technology “Omega-C” introduction in the experimental work helped a coach and a sports doctor to monitor the quality and level of adaptive processes of 15-16 year-old athletes. It provided balance between high physical loads and health preservation. Physical state deviations registration among biathletes helped to correct timely the training process.

The most useful application of PV solar power in Russia are autonomous power systems in regions with high costs of organic fuels (due to transportation problems). Effective application of PV power needs comprehensive data analysis for solar energy resources, electric and heat load graphs and fuel costs. This paper is devoted to climate and power load data analysis for Russian Far East regions (in connection with PV application) and PV-based power plant mathematical modeling for several locations.

The object of this study is the interaction of the cyclic anhydride 2 of (18 α,19 β)-19-hydroxy-2,3-secooleanane-2,3,28-trioic acid 28,19-lactone ( 1) with primary and secondary amines. It was shown that the products of steric control (the corresponding 2-amino-2-oxo-3-oic acids=2-amides) were formed solely upon the opening of the anhydride cycle by secondary amines ( Scheme 2), whereas the interaction with primary amines yielded a mixture of isomeric amides ( Scheme 10). In the latter case, the solvent provided a noticeable effect on the reaction selectivity, which was demonstrated in the case of 4-methoxybenzylamine. The interaction between the resulting 3-amides and oxalyl chloride yielded the corresponding cyclic imides, whereas under these conditions, 2-amides formed spiropyrrolidinetriones ( Scheme 4). [ABSTRACT FROM AUTHOR]

A series of deoxycholic acid (DCA) amides containing benzyl ether groups on the steroid core were tested against the tyrosyl-DNA phosphodiesterase 1 (TDP1) and 2 (TDP2) enzymes. In addition, 1,2,4- and 1,3,4-oxadiazole derivatives were synthesized to study the linker influence between a para-bromophenyl moiety and the steroid scaffold. The DCA derivatives demonstrated promising inhibitory activity against TDP1 with IC50 in the submicromolar range. Furthermore, the amides and the 1,3,4-oxadiazole derivatives inhibited the TDP2 enzyme but at substantially higher concentration. Tryptamide 5 and para-bromoanilide 8 derivatives containing benzyloxy substituent at the C-3 position and non-substituted hydroxy group at C-12 on the DCA scaffold inhibited both TDP1 and TDP2 as well as enhanced the cytotoxicity of topotecan in non-toxic concentration in vitro. According to molecular modeling, ligand 5 is anchored into the catalytic pocket of TDP1 by one hydrogen bond to the backbone of Gly458 as well as by π–π stacking between the indolyl rings of the ligand and Tyr590, resulting in excellent activity. It can therefore be concluded that these derivatives contribute to the development of specific TDP1 and TDP2 inhibitors for adjuvant therapy against cancer in combination with topoisomerase poisons. [ABSTRACT FROM AUTHOR]