A. A. Balandina

Deoxygenation of Some α-Dicarbonyl Compounds by Tris(diethylamino)phosphine in the Presence of Fullerene C60

The reactions of such cyclic α-diketones as acenaphthenequinone, aceanthrenequinone, and N-alkylisatins, with hexaethyltriaminophosphine in the presence of the fullerene C(60), lead to the formation of methanofullerene derivatives under mild conditions. This process proceeds via deoxygenation of the dicarbonyl compound by the P(III) derivative and is likely to involve the intermediate formation of α-ketocarbenes. The structure of some methanofullerenes has been confirmed by NMR and XRD. The electrochemical behavior of the methanofullerenes was also investigated.

Wagner-Meerwein rearrangement of steviol 16α,17- and 15α,16-epoxides

Abstract16α,17- and 15α,16-Epoxy derivatives of diterpenoid steviol having ent-kaurane structure were found for the first time to undergo Wagner-Meerwein rearrangement in alkaline medium or by the action of boron trifluoride-diethyl ether complex to give products with ent-beyerane structure. The geometric parameters of steviol 16α,17- and 15α,16-epoxides were determined by X-ray analysis.

Geometrical Configuration of 12,13-Epoxyoctadeca-9,11-dienoic Acid, a Product of the Reaction Catalyzed by Flaxseed Allene Oxide Synthase (CYP74A)

The geometrical configuration of a short-living allene oxide reaction product that arises under the catalysis by flaxseed allene oxide synthase (CYP74A) was studied by NMR spectroscopy. The structure of (9Z, 11E)-12,13-epoxyoctadeca-9,11-dienoic acid was established for it from the results of the nuclear Overhauser effect measurements.

Synthesis and properties of new triazole methanofullerenes under the “click-chemistry” conditions

The “click-chemistry” methods were used for the first time to synthesize new 1,2,3-triazole derivatives of fullerene, promising for the study of their biological activity, as well as for the preparation of new fullerene-containing materials on their basis. The purity and composition of the compounds synthesized were confirmed by MALDI-TOF mass spectrometry and HPLC, their structures were confirmed by a combination of 2D NMR homo- and heteronuclear correlation.

Norditerpenoid alkaloids from Aconitum septentrionale K

Two new alkaloids, Septonine (C35H44N2O9) and Septontrionine (C25H39NO6) were isolated from the roots of Aconitum septentrionale K. According to the 1H and 13C NMR, IR, and mass spectra, Septonin and Septontrionin were assigned the structures of 20-ethyl-7-hydroxy-1α,14α,16β-trimethoxy-6-oxo-17(7→8)abeoaconitan-4-ylmethyl 2-(2,5-dioxopyrrolidin-l-yl)benzoate and 20-ethyl-7-hydroxy-1α,14α,16β-trimethoxy-4-methoxymethyl-17(7→8)abeoaconitan-6-one, respectively.

Proton-acceptor properties of azahomofullerene and fullerenoaziridine containing a cyanuric acid fragment

Abstract13C and 1H NMR and UV spectral studies on 1,3-diallyl-5-[4-(azahomo[60]fullereno)butyl]hexahydro-1,3,5-triazine-2,4,6-trione ([5,6]-open isomer) and 1,3-diallyl-5-[4-(aziridino[60]fullereno)butyl]hexahydro-1,3,5-triazine-2,4,6-trione ([6,6]-closed isomer), as well as quantum-chemical calculations, showed that only the latter possesses weakly basic properties.

Nonracemic menthyl phosphorylacetates

Phosphorylacetic acid esters containing the menthoxy fragment at the phosphorus atom or at the carbonyl group were synthesized. The configurations of the enantiomerically pure compounds, viz., methyl (ethoxy)(menthyloxy)phosphorylacetate and menthyl [(2-chloro-ethoxy)(4-dimethylaminophenyl)phosphoryl]acetate, were established by X-ray diffraction and NMR spectroscopy.

Synthesis of the individual regioisomer of the bisadduct of fullerene C60 with tert-butyl 11-azido-3,6,9-trioxaundecanoate

At 130 °C the reaction of fullerene C60 with 1-azido-9-tert-butoxycarbonyl-3,6,9-trioxanonane occurs regioselectively affording one regioisomer of the bisadduct.

Synthesis and electrochemical properties of individual isomers of isocyanurate-substituted bis-organodiazadihomofullerenes

The reactions of fullerene C60 with isocyanurate-substituted azides afforded individual regioisomers of bis-adducts. The structures of the regioisomers depend on the structure of the organic fragment in azide and are determined primarily by the bulkiness of this fragment.

Condensation of Diethyl 2,4,6-Trioxoheptanedioate with 2-(Aryliminomethyl)phenols. A New Synthesis of Chromeno(4,3-b)pyridines

Condensation of diethyl 2,4,6-trioxoheptanedioate with 4-methoxy-2-(4-methylphenyliminomethyl)-phenol in acetone gave diethyl 5-hydroxy-9-methoxy-1-(4-methylphenyl)-4-oxo-1,4a,5,10b-tetrahydro-4Hchromeno[ 4,3-b]pyridine-2,5-dicarboxylate as a mixture of diastereoisomers. The major (4aR,5R,10aR)-isomer was isolated as individual substance, and its structure was proved by X-ray analysis.