Tandem Glycosyl Iodide Glycosylation and Regioselective Enzymatic Acylation Affords 6-O-Tetradecanoyl-α-d-cholesterylglycosides
نویسندگان
چکیده
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% overall yields from free sugars. The tandem step-economy sequence provides novel analogues to facilitate glycolipidomic profiling.
منابع مشابه
Chemoenzymatic synthesis of cholesteryl-6-O-tetradecanoyl-α-D-glucopyranoside: a product of host cholesterol efflux promoted by Helicobacter pylori.
In a three-step protocol involving regioselective enzymatic acylation, per-O-trimethylsilylation, and a one-pot α-glycosidation-deprotection sequence, cholesteryl-6-O-tetradecanoyl-α-D-glucopyranoside (α-CAG) of Helicobacter pylori is afforded starting from glucose in an overall yield of 45%. The production of CAG can be scaled to make purified quantities available to the biological community f...
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