RESUMO
7-Deoxy-1,2:3,4-di-O-isopropylidene-alpha-D-galacto-heptopyranos-6-ulose (1) reacted with carbon disulphide and methyl iodide in the presence of a base to furnish 7,8-dideoxy-1,2:3,4-di-O-isopropylidene-8,8-[bis(methylthio)]-alpha-D-galacto-oct-7-enopyranos-6-ulose (2). This 'push-pull' activated unsaturated monosaccharide underwent a ring closure reaction with hydrazine hydrate to give the 'inversed' C-nucleoside analogue 3. Compound 1 and malononitrile yielded the 7-cyano-6,7-dideoxy-1,2:3,4-di-O-isopropylidene-6-methyl-alpha-D-galacto-oct-6-enopyranurononitrile (4). Treatment of 4 with carbon disulphide and methyl iodide in the presence of a base afforded the sugar 'push-pull' butadiene 5 which was transformed into the pyridine nucleoside analogue 6.
Assuntos
Monossacarídeos/síntese química , Nucleosídeos/síntese química , Antineoplásicos/síntese química , Antivirais/síntese química , Piridinas/síntese químicaRESUMO
The reaction of methyl 4,6-O-benzylidene-3(2)-deoxy-alpha-D-erythro- hexopyranosid-2(3)-ulose with carbon disulfide, alkyl iodide, and sodium hydride gave methyl 4,6-O-benzylidene-3(2)-[bis(alkylthio)methylene]-3(2)-deoxy-alpha-D- erythro-hexopyranosid-2(3)-uloses. Methyl 4,6-O-benzylidene-2-[bis(methylthio)-methylene]-2-deoxy-alpha-D- erythro-hexopyranosid-3-ulose (5) reacted with aromatic amines to give, in a rearrangement process, N-aryl-2-aryliminomethyl-4,6-O-benzylidene-2-deoxy- alpha-D-erythro-hex-1-enopy-ranosylamin-3-uloses. The reaction of 5 with hydrazine hydrate afforded 5-methylthio-(methyl 4,6-O-benzylidene-2,3-dideoxy-alpha-D-erythro-hexopyranosido)[3,2- c]pyrazole.