title: Preparation of derivatives of L-idose and L-iduronic acid from 1,2-O-isopropylidene-alpha-D-glucofuranose by way of acetylenic intermediates.
abstract: The products (1) from the periodate oxidation of 1,2-O-isopropylidene-alpha-D-glucofuranose were converted by ethynylmagnesium bromide into a separable, 14:11 mixture of 6,7-dideoxy-1,2-O-isopropylidene-beta-L-ido-hept-6-ynofuranose (2) and its alpha-D-gluco analog 3. These crystalline products were further characterized as their respective 3,5-diacetates (5 and 7) and 3,5-dibenzoates (4 and 6). Ozonolysis of 2 and 3 led to 1,2-O-isopropylidene-beta-L-idofuranurono-6,3-lactone (8) and its alpha-D-gluco analog 9, respectively; similar ozonolysis of the dibenzoates 4 and 6, followed by treatment with diazomethane, gave methyl 3,5-di-O-benzoyl-1,2-O-isopropylidene-alpha-L-idofuranuronate (10) and its alpha-D-gluco analog 11, respectively. Diborane reduction of the ozonolysis products from 4 gave 1,2-O-isopropylidene-beta-tl-idofuranose (13) as its 3,5-dibenzoate (12), and a similar sequence was performed with 6. The propargylic alcohols 2 and 3 were reduced by lithium aluminum hydride, in high yield, to the allylic alcohol analogs 15 and 16, further characterized as their 3,5-dibenzoates 17 and 18; compounds 15 and 16 were also obtainable by vinylation of compounds 1. The two series of derivatives in this work, epimeric at C-5, were examined comparatively by polarimetry and p.m.r. spectroscopy.
mesh_terms: D000114:Acetylene; D055598:Chemical Phenomena; D002621:Chemistry; D007067:Iduronic Acid / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D008968:Molecular Conformation; D009005:Monosaccharides / Q000138:chemical synthesis; D014574:Uronic Acids / Q000031:analogs & derivatives*
chemical_list: D009005:Monosaccharides; D014574:Uronic Acids; D007067:Iduronic Acid; D000114:Acetylene