The influence of low- and high-molecular chelating additives upon the reduction of nitrotetrazolium blue to formazane in the presence of d-metal cations

The influence of high- and low-molecular additives upon the reduction of nitrotetrazolium blue to formazane in the presence of d-metal cations was studied. It was shown that the introduction of chelating additives did not essentially change the earlier found regularities in the variation of anti- and prooxidant activity within the range of d-metal cations. In most cases the observed effects may be understood in the terms of the theory of hard and soft acids and bases.     

Use of 13C NMR Spectroscopy to Establish the Structure of 6(7)-R-Quinoxaline N,N′-Dioxides

The effect of substituents in position 6 on the positions of the signals of the carbon atoms in the ¹³C NMR spectra of substituted 1,2,3,4-tetrahydro-5,10-phenazine N,N′-dioxides has been analyzed, increments of substituents have been found, and a scheme has been proposed for the calculation of the chemical shifts of carbon atoms in the ¹³C NMR spectra of 6(7)-R-quinoxaline N,N′-dioxides. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, 1076–1080, July, 2005.