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Efficient synthesis of α-galactosylceramide and its C-6 modified analogs.

ABSTRACT: The synthesis of α-galactosylceramide (KRN7000) and its C-6 modified analogs remains a challenge due to the difficult α-1,2-cis-glycosidic bond. A non-participating benzyl (Bn) protecting group has been commonly used to favor the α-glycosylation product. Here, we report the α-selective glycosylation by using a bulky 4,6-O-di-tert-butylsilylene (DTBS) galactosyl donor, regardless of the 2-benzoyl (Bz) participating group. Compared with Bn, Bz groups can be selectively removed in basic conditions without impacting the C-6 azide modification. The azide has the potential for clicking with alkyne or being easily transformed to other functional groups.

SUBMITTER: Li H

PROVIDER: S-EPMC9732566 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Efficient synthesis of α-galactosylceramide and its C-6 modified analogs.

Li Huiting H Mao Hongzhao H Chen Chao C Xu Ying Y Meng Shuai S Sun Tiantian T Zong Chengli C

Frontiers in chemistry 20221125

The synthesis of α-galactosylceramide (KRN7000) and its C-6 modified analogs remains a challenge due to the difficult α-1,2-<i>cis</i>-glycosidic bond. A non-participating benzyl (Bn) protecting group has been commonly used to favor the α-glycosylation product. Here, we report the α-selective glycosylation by using a bulky 4,6-O-di-<i>tert</i>-butylsilylene (DTBS) galactosyl donor, regardless of the 2-benzoyl (Bz) participating group. Compared with Bn, Bz groups can be selectively removed in bas ...[more]

PMID: 36505742

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