Synthesis 2003(1): 0129-0135
DOI: 10.1055/s-2003-36261
PAPER
© Georg Thieme Verlag Stuttgart · New York

Enantioselective Syntheses of xylo-C18-Phytosphingosines using Double Stereodifferentiation

Rodney A. Fernandes, Pradeep Kumar*
Division of Organic Chemistry: Technology, National Chemical Laboratory, Pune 411 008, India
Fax: +91(20)5893614; e-Mail: tripathi@dalton.ncl.res.in;
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Publikationsverlauf

Received 19 July 2002
Publikationsdatum:
18. Dezember 2002 (online)

Abstract

The concept of double stereodifferentiation in Sharpless asymmetric dihydroxylation has been studied and the results obtained are applied to the diastereoselective syntheses of xylo-isomers of C18-phytosphingosine. The diastereomeric mixture obtained could be separated by column chromatography. Thus, the l-xylo-(2R,3S,4S)-C18- and d-xylo-(2S,3R,4R)-C18-phytosphing­osines as their tetraacetate derivatives were synthesized in dia­stereomerically pure form.

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The enantiomeric excess of the corresponding dibenzoate was determined by HPLC using Lichrocart 250-4 (4 mm ID × 25 cm) HPLC-Cartridge (R. R.-Whelk-01), 10% i-PrOH in hexane, 1 mL/min.

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The diastereomeric ratio was determined by 1H NMR and 13C NMR spectroscopy.