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A selective and mild glycosylation method of natural phenolic alcohols.

ABSTRACT: Several bioactive natural p-hydroxyphenylalkyl ?-D-glucopyranosides, such as vanillyl ?-D-glucopyranoside, salidroside and isoconiferin, and their glycosyl analogues were prepared by a simple reaction sequence. The highly efficient synthetic approach was achieved by utilizing acetylated glycosyl bromides as well as aromatic moieties and mild glycosylation promoters. The aglycones, p-O-acetylated arylalkyl alcohols, were prepared by the reduction of the corresponding acetylated aldehydes or acids. Various stereoselective 1,2-trans-O-glycosylation methods were studied, including the DDQ-iodine or ZnO-ZnCl2 catalyst combination. Among them, ZnO-iodine has been identified as a new glycosylation promoter and successfully applied to the stereoselective glycoside synthesis. The final products were obtained by conventional Zemplén deacetylation.

SUBMITTER: Mastihubova M

PROVIDER: S-EPMC4901888 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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A selective and mild glycosylation method of natural phenolic alcohols.

Mastihubová Mária M Poláková Monika M

Beilstein journal of organic chemistry 20160315

Several bioactive natural p-hydroxyphenylalkyl β-D-glucopyranosides, such as vanillyl β-D-glucopyranoside, salidroside and isoconiferin, and their glycosyl analogues were prepared by a simple reaction sequence. The highly efficient synthetic approach was achieved by utilizing acetylated glycosyl bromides as well as aromatic moieties and mild glycosylation promoters. The aglycones, p-O-acetylated arylalkyl alcohols, were prepared by the reduction of the corresponding acetylated aldehydes or acids ...[more]

PMID: 27340444

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