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Tandem glycosyl iodide glycosylation and regioselective enzymatic acylation affords 6-O-tetradecanoyl-?-d-cholesterylglycosides.

ABSTRACT: A generalized synthesis of ?-d-cholesterylglycosides has been achieved using one-pot per-O-trimethylsilyl glycosyl iodide glycosidation. Both cholesteryl ?-d-glucopyranoside (?CG) and cholesteryl ?-d-galactopyranoside were prepared in high yield. These compounds were further esterified using regioselective enzymatic acylation with tetradecanoyl vinyl ester to afford 6-O-tetradecanoyl-?-d-cholesteryl glucopyranoside (?CAG) of Helicobacter pylori and the corresponding galactose analogue in 66-78% overall yields from free sugars. The tandem step-economy sequence provides novel analogues to facilitate glycolipidomic profiling.

SUBMITTER: Davis RA

PROVIDER: S-EPMC4156253 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

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Tandem glycosyl iodide glycosylation and regioselective enzymatic acylation affords 6-O-tetradecanoyl-α-d-cholesterylglycosides.

Davis Ryan A RA Fettinger James C JC Gervay-Hague Jacquelyn J

The Journal of organic chemistry 20140813 17

A generalized synthesis of α-d-cholesterylglycosides has been achieved using one-pot per-O-trimethylsilyl glycosyl iodide glycosidation. Both cholesteryl α-d-glucopyranoside (αCG) and cholesteryl α-d-galactopyranoside were prepared in high yield. These compounds were further esterified using regioselective enzymatic acylation with tetradecanoyl vinyl ester to afford 6-O-tetradecanoyl-α-d-cholesteryl glucopyranoside (αCAG) of Helicobacter pylori and the corresponding galactose analogue in 66-78% ...[more]

PMID: 25093454

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