Hexitols 1,2,3-trideoxy

Anhydro-l,3,6-trideoxy-L-rtbo-hexitol-l-yl)-trimethyl-ammonium chloride [L-(+)-Muscarine chloride] 2,5-Anhydro-/3-D-arabinofuranose 179-80... 

The above compound, l,5-anhydro-2,3,4-trideoxy-6-0-triphenyl-methyl-D-gZt/cero-hexitol (4.0 grams) was dissolved in 75 ml of chloroform. Dry hydrogen bromide was bubbled through the solution kept at 0°C until TLC examination showed all the starting material had disappeared. The solution was concentrated at 30 °C and 13 mm pressure to a semi-solid mass. The pressure was then reduced to 0.08 mm, and the... 

The l,2,6-trideoxy-l,6-imino-D-ara6m<9-hexitol was found to inhibita-D-glucosidase (Ki 12 pM, Bakers yeast), (3-D-glucosidase (Ki 51 pM, Almonds) and (3-D-galactosidase (Ki 13 pM, E. coli) as well, indicating the flexibility of the 7-membered ring system (14). 

Methyl 4,6-0-benzylidene-3-deoxy-a-D-ribo-hexopyranoside (56) was benzoylated, debenzylidenated, and partially p-toluenesulfon-ylated to 57 this was converted into 58 by reaction with sodium iodide, followed by catalytic reduction. The methanesulfonate of 58 was converted into 59 by reaction with sodium azide in N,N-dimethylformamide, and 59 was converted into 4-azido-3,4,6-trideoxy-a-D-xylo-hexose (60) by acetolysis followed by alkaline hydrolysis. Reduction of 60 with borohydride in methanol afforded 61, which was converted into 62 by successive condensation with acetone, meth-anesulfonylation, and azide exchange. The 4,5-diazido-3,4,5,6-tetra-deoxy-l,2-0-isopropylidene-L-ara/uno-hexitol (62) was reduced with hydrogen in the presence of Raney nickel, the resultant diamine was treated with phosgene in the presence of sodium carbonate, and the product was hydrolyzed under acidic conditions to give 63. The overall yield of 63 from 56 was 4%. The next three reactions (with sodium periodate, the Wittig reaction, and catalytic reduction) were performed without characterization of the intermediate products, and gave (+)-dethiobiotin methyl ester indistinguishable from an authentic sample thereof prepared from (+)-biotin methyl ester. 

Anhydro-L-idose has been converted into 2,5-anhydro-4-0-benzoyl-l-iodo-l,3,6-trideoxy-L-ara6wo-hexitol, a key synthon in the synthesis of (-)-a//o-mu-scarine ... 

Reaction of (R)/(S)-3-cyano-2-hydroxypropanal with lithium hydroxypyruvate under trans ketolase control followed by a palladium catalyzed-reductive amination afforded l,2,5-trideoxy-l,5-imino-D-arabi o-hexitol (fagomine) ... 

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