Synthesis of derivatives of pentopyranic acid

N⁴-Benzoylcytosine 1-(methyl 2,3,4-tri-O-acetyl--D-glucopyranosiduronate) has been obtained with a yield of 70% by the glycosylation of the trimethylsilyl derivative of N⁴-benzoylcytosine with methyl 1,2,3,4-tetra-O-acetyl--D-glucopyranuronate in the presence of three equivalents of SnCl₄ as condensing agent. Cytosine 1-(-D-glucopyranosiduronamide) (IV) — the amide of pentopyranic acid — has been synthesized in practically quantitative yield by the ammonolysis of the nucleoside (I).Peat Institute, Academy of Sciences of the Belorussian SSR, Minsk. Institute of Bioorganic Chemistry, Academy of Sciences of the Belorussian SSR, Minsk. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 617–619, September–October, 1983.     

Synthesis of 2-acyl-4-hydroxycyclohexane-1,3-diones — Kairomones and protective substances of some insects

The synthesis of some derivatives of β-triketones based on a new synthon — 4-hydroxycyclohexane-1,3-dione — is described. Using the proposed scheme, 4-hydroxy-2-(octadec-9Z,12Z-dienoyl)cyclohexane-1,3-dione, a kairomone of some species of Lepidoptera, has been obtained. Institute of Bioorganic Chemistry, Belorussian Academy of Sciences, Minsk. Belorussian State University, Minsk. Translated from Khimiya Prirodnikh Soeinenii, No. 2, pp. 197–203. March–April, 1994.     

Synthesis of 24-epiteasterone

Starting from ergosterol, the synthesis of the brassinosteroid 24-epiteasterone has been achieved by the use of a new scheme for introducing a 3-hydroxy-6-keto group as the result of the Birch reduction of the corresponding 5-hydroxy-⁷-3,6-dione.Institute of Bioorganic Chemistry, Belorussian Academy of Sciences, Minsk. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 224–227, March–April, 1992.     

Investigation of the regio-and stereoselectivity of the annelation reaction of cyclic schiff base with structurally asymmetrical β,β′-triketones. Synthesis and properties of 17-acetoxy-8-aza-D-homogona-12,17a-diones

Annelation ([2+4]-cyclocondensation) of 3,4-dihydroisoquinolines and 2-acetyl-4-acetoxycyclohexane-1,3-dione gives 17-acetoxy-8-aza-D-homogona-12,17a-diones as a mixture of the C(9),C(17)-stereoisomers with the (9R,17S: 9S,17R) racemic pair predominating.Institute of Bioorganic Chemistry, National Academy of Sciences of the Belorussian Republic, Minsk 220141; e-mail: prostan@ns.iboch.ac.by. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1092–1099, August, 2000.     

Synthesis of natural phytosteroids of the 6-ketostigmastane series and compounds related to them

Preparative methods of synthesizing a number of natural 6-ketosteroids and 6-alcohols related to them from -sitosterol have been developed.Institute of Bioorganic Chemistry, Academy of Sciences of the Belorussian SSR, Minsk. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 771–776, November–December, 1990.     

Recyclization of spiro[3a-Hydroxypiperidin-4,2′-oxiranes] in basic medium

It is shown that heating spiro[3a-hydroxypiperidin-4,2-oxiranes] in aqueous base gives rearrangement into derivatives of 3,4-epoxypiperidines. The structures of the latter were confirmed by spectral data and by chemical informations.Belorussian State Technological University, Minsk 220030. Translated from Khimiya Geterotsiklicheskikh Soedineii, No. 9, pp. 1213–1215, September, 1994. Original article submitted July 29, 1994.