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Syntheses of biologically important carbohydrates 35. synthesis of exocyclic saccharide enol ethers and their reaction to branched chain carbohydrates






Liebigs Annalen der Chemie (4): 613-624

Syntheses of biologically important carbohydrates 35. synthesis of exocyclic saccharide enol ethers and their reaction to branched chain carbohydrates

Wittig olefination of the 3-uloses 1 and 9 leads to the exocyclic (E)- and (Z)-enol ethers 2 and 3 or 11 and 10, respectively. On cis-hydroxylation these are uniformly transformed into the hydroxyformy-branched gluco derivatives 4 and 8, respectively. Acidolysis of 2a as well as mercuri or iodo hydroxylation with subsequent reduction give the 3-C-formyl-branched sugars 12 and 13. Alternatively, the latter may also be obtained by treatment of the ulose 1 with tosylmethyl isocyanide via the cyano-branched compound 16. Addition of iodine/silver isocyanate to 2a and subsequent methanolysis gives the epimeric 3-deoxy-3-iodo-3'-aminals 14 and 15 which on treatment with base yield the substituted aziridine 17 or the branched olefin sugar derivative 18, respectively.


Accession: 006559695



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