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The influence of preirradiation with an electron beam from a linear resonance electron accelerator in flowing argon on the structure and properties of the 1% Pt/H pentasil catalyst was studied. The support structure was studied by x-ray diffraction and low-temperature nitrogen adsorption. No changes in the crystal structure and pentasil specific surface area were observed in the irradiation dose range from 120 to 900 Mrad at an average electron energy of 7.7 MeV. The electron beam treatment resulted in a considerable increase in the catalytic activity of the Pt/H pentasil in gas-phase toluene hydrogenation as a model reaction. The results obtained by IR spectroscopy of adsorbed CO and X-ray diffraction data suggested that the increase in the catalyst activity after electron beam irradiation is due to changes in the size and charge of the Pt particles.

The effect of electron irradiation on the properties of the systems 1% Pd/C, 1% Pd/Al2O3, and 1% Pd/TiO2 is studied in gas-phase and liquid-phase toluene hydrogenation. An increase in the irradiation dose to 120–900 Mrad increases the catalytic activity by a factor of 2–8 relative to that of the original system. XPS data for the Pd/C catalyst suggest that, after irradiation with high-energy electrons, the metal particles are stabilized on the surface of the carbon support, their degree of dispersion is increased, and their sintering is suppressed. These inferences are consistent with the observed changes in catalytic properties.

Hydrolysis of 2-hydroxyethyl methacrylate in aqueous solutions, as influenced by pH, temperature, and substrate concentration, was studied. In concentrated solutions, the monomer forms associates, which promotes its hydrolysis.

Two new alkaloids — umbrofine and 6-acetylumbrofine — have been isolated fromAconitum umbrosum, and their structures have been established on the basis of spectral characteristics.

Mesaconitine, hypaconitine, and the new alkaloid taurenine have been isolated from the roots of the cultivated speciesAconitum tauricum, and the structure of taurenine has been established.

The electron-beam irradiation of Pd/Al2O3 and Pd/C increased dispersion of Pd nanoparticles and activity in toluene hydrogenation by a factor of 3–4.

A new base — septenine — has been isolated from the roots of Aconitum septentrionale, and its structure has been established on the basis of spectra characteristics.

A new alkaloid — leuconine — has been isolated from the epigeal parts ofAconitum leucostomum andA. septentrionale, and its structure has been established on the basis of spectral characteristics.

A quantitative determination of the main components of the saponified total alkaloids from the epigeal part ofAconitum leucostomum has been made by the integrated ion current mass-spectrometric technique. The minor components have been characterized by a combination of the method of metastable defocusing with measurements of the elementary compositions of the ions.

The structure of a new alkaloid sepaconitine isolated from the epigeal part ofAconitum septentrionale has been established on the basis of spectral characteristics.

The structure of the new alkaloid N-acetylsepaconitine, and also of a base (IV) formed from lycaconitine in the process of ethanolic extraction in an alkaline medium have been determined on the basis of spectral characteristics. Both bases were isolated from the epigeal part ofAconitum leucostomum.

Fragmentation under electron impact of eleven C18-diterpene alkaloids with an oxygen function at C-4 has been investigated. The contributions of various modes of forming the (M - CH3)+ ions have been determined. The mechanism of the appearance of the fragments (M - CH3)+ and (M - OCH3)+ at the expense of the methoxy groups at C-14 and C-16 has been considered. The characteristic nature of the parameters of the metastable peaks in the transitions to these daughter ions has been shown. Minor directions of the fragmentation of 3,4-epoxy- and 4-hydroxy bases have been characterized.

The new C18 diterpene alkaloids monticamine and monticamine have been isolated from the epigeal part ofAconitum monticola Steinb. Their structures have been established on the basis of the results of1H and13C NMR, IR, and mass spectra and also of chemical transformations.

A structure has been proposed for lappaconitine on the basis of its chemical and spectral characteristics.

1. The structure of the new alkaloid lapaconidine has been established. 2. The structure proposed previously for the product of the reaction of lappaconine with sulfuric acid has been confirmed on the basis of chemical and spectral studies.

The main routes of fragmentation of diterpene alkaloids with the lycoctonine skeleton under the action of electron impact are discussed.

The epigeal part ofAconitum monticola Steinb. has yielded two C18 diterpene alkaloids which, on the basis of the results of a study of NMR, IR, and mass spectra, and also of chemical transitions, have been shown to be identical with synthetic deoxydelosline and dihydromonticamine. This is the first time that these alkaloids have been found in a plant.

Together with delcorine, lycoctonine, eldeline, dehydrodelcorine, ilidine, browniine, and dictyocarpinine, we have isolated a new alkaloid, delcoridine, from the epigeal part ofDelphinium iliense Huth. Its structure has been established on the basis of the results of a study of the chemical transformations and spectra characteristics. This is the first time that the alkaloid dictyocarpinine has been isolated from this plant.