Yu. V. Gatilov

Stable nitroxyl radicals with a hydrogen atom at α-carbon atom of nitroxyl group

Nitroxyl radicals containing the diphenylmethyl group as one of the substituents at the nitroxyl group are stable compounds that can be isolated in an individual state.N-(2-Hydroxy-3-methyl-2-phenylcyclohexyl)-N-diphenylmethylnitroxyl was characterized by X-ray diffraction analysis for the first time.

Reactions of N,N-(dialkyl)arylthioacetamides with dialkyl acetylenedicarboxylates

Abstract2-(Alkoxycarbonylmethylidene)-4-aryl-5-(dialkylamino)thiophen-3(2H)-ones were synthesized by condensation of N,N-(dialkyl)arylthioacetamides with dialkyl acetylenedicarboxylates. Intermediate substituted vinylic sulfides were isolated. When heated or in the presence of an acid or a base, they undergo cyclization into thiophenes.

Synthetic transformations of methylenelactones of eudesmanic type. Behavior of isoalantolactone under the conitions of heck reaction

By Heck reaction of isoalantolactone with aryl bromides or aryl iodides (3aR,4aS, 8aR,9aR,E)-3-arylmethylidene-8a-methyl-5-methylidenedecahydronaphtho[2,3-b]furan-2(3H)-ones and (4aS,8aR,9aS)-3-arylmethyl-8a-methyl-5-methylidene-4a,5,6,7,8,8a,9,9a-octahydronaphtho[2,3-b]furan-2(4H)-ones, products of the double bond shift, were synthesized. The yields of the arylation products depend on the nature of the catalytic system and on the structure of the aryl halide. The structures of (3aR,4aS,8aR,9aR,E)-3-(3,4-dimethoxybenzylidene)-8amethyl-5-methylidenedecahydronaphtho[2,3-b]furan-2(3H)-one and (4aS,8aR,9aS)-3-(2-methylsulfanylbenzyl)-8amethyl-5-methylidene-4a,5,6,7,8,8a,9,9a-octahydronaphtho[2,3-b]furan-2(4H)-one were proved by XRD analysis.

New chiral ligands based on (+)-α-pinene

A number of new chiral ligands were synthesized starting from an accessible monoterpene, (+)-α-pinene. The new ligands were used in the vanadium-catalyzed oxidation of sulfides to chiral sufoxides.

Synthesis of spin-labeled amides of 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (trolox)

Reaction of 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (trolox) with 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl, 3-amino-2,2,5,5-tetramethylpyrrolidine-1-oxyl, and 3-aminomethyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl synthesized the corresponding spin-labeled amides. The synthesized compounds exhibited antioxidant potential and were promising for application in biomedical studies using magnetic-resonance imaging (MRI).

Molecular and crystal structure of 1-amino-X-pyrazinium mesitylenesulfonates

X-Ray diffraction analysis was performed of 1-amino-X-pyrazinium mesitylenesulfonates (X=H, 2-NH2, 3-NHCOMe, 3-OMe, 3-Cl). In all events save 1,2-diaminopyrazinium cation the bond length of N-NH2 was shorter than that of N-N bond but considerably longer than the length of the double bond N=N. In the 1,2-diaminopyrazinium cation the bond distance C2-NH2 was close to the length of a common double bond C=N indicating the iminium character of the cation. Quantum-chemical calculations [AM1, PM3, DFT/(PBE/3z), B3LYP/6-31G++(2d,p)] provided the geometry of cations similar to the experimental one. In the crystals under investigation motifs were observed of 0D, 1D, and 2D type mainly due to hydrogen bonds N-H···O and π-stacking interactions of the aromatic rings.

Sesquiterpene lactones and flavonoids from Artemisia albida

The five known lactones matricarin, austricin, canin, and achillin guaianolides and argolide germacranolide and the two flavonoids eupatilin and its 7-O-methyl ester were isolated for the first time from the aerial part of Artemisia albida Willd. The structure of eupatilin was confirmed by an x-ray structure analysis.

Synthesis of (7-polyfluoroalkyl)pyrazolo[1,5-a]pyrimidines based on lithium fluorine-containing β-diketonates

The reactions of Li enolates of fluorine-containing β-diketones with 3-aminopyrazoles afforded (7-polyfluoroalkyl)pyrazolo[1,5-a]pyrimidines. The structure of 3-bromo-2-methyl-5-phenyl-7-trifluoromethylpyrazolo[1,5-a]pyrimidine was established by X-ray diffraction analysis.

3-Oxocostusic acid fromArtemisia altaiensis

From the epigeal part ofArtemisia altaiensis Krash. we have isolated 3-oxocostus acid (selina-4,11(13)-dien-3-on-12-oic acid), the structure of the molecule of which has been confirmed by x-ray structural analysis, while its absolute configuration has been established from the results of circular dichroism.

MOLECULAR STRUCTURE OF AZACHALCOGENENES WITH AROMATIC SUBSTITUENTS

The molecular structure of acyclic and cyclic azachalcogenenes with aromatic substituents is analyzed and compared with related compounds using the data of XRD, NMR, and quantum chemical calculations.