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Synthesis of cholesteryl-?-D-lactoside via generation and trapping of a stable ?-lactosyl iodide.

ABSTRACT: The generation of ?-lactosyl iodide was carried out under non-in situ-anomerization, metal free conditions by reacting commercially available ?-per-O-acetylated lactose with trimethylsilyl iodide (TMSI). The ?-iodide was surprisingly stable as evidenced by NMR spectroscopy. Introduction of octanol or cholesterol under microwave conditions gave high yields of ?-linked glycoconjugates. Careful analysis of the reaction products and mechanistic considerations suggest an acid catalyzed rearrangement that provides ?-linked glycosylation products with a free C2-hydroxyl. Accessibility to these compounds may further advance glycolipidomic profiling of immune modulating bacterial derived-glycans.

SUBMITTER: Davis RA

PROVIDER: S-EPMC4629507 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Synthesis of cholesteryl-α-D-lactoside via generation and trapping of a stable β-lactosyl iodide.

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

Tetrahedron letters 20150508 23

The generation of β-lactosyl iodide was carried out under non-in situ-anomerization, metal free conditions by reacting commercially available β-per-<i>O</i>-acetylated lactose with trimethylsilyl iodide (TMSI). The β-iodide was surprisingly stable as evidenced by NMR spectroscopy. Introduction of octanol or cholesterol under microwave conditions gave high yields of α-linked glycoconjugates. Careful analysis of the reaction products and mechanistic considerations suggest an acid catalyzed rearran ...[more]

PMID: 26543257

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