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Synthesis of icariin from kaempferol through regioselective methylation and para-Claisen-Cope rearrangement.

ABSTRACT: The hemisynthesis of the naturally occurring bioactive flavonoid glycoside icariin (1) has been accomplished in eleven steps with 7% overall yield from kaempferol. The 4'-OH methylation of kaempferol, the 8-prenylation of 3-O-methoxymethyl-4'-O-methyl-5-O-prenyl-7-O-benzylkaempferol (8) via para-Claisen-Cope rearrangement catalyzed by Eu(fod)3 in the presence of NaHCO3, and the glycosylation of icaritin (3) are the key steps.

SUBMITTER: Mei Q

PROVIDER: S-EPMC4578360 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Synthesis of icariin from kaempferol through regioselective methylation and para-Claisen-Cope rearrangement.

Mei Qinggang Q Wang Chun C Zhao Zhigang Z Yuan Weicheng W Zhang Guolin G

Beilstein journal of organic chemistry 20150720

The hemisynthesis of the naturally occurring bioactive flavonoid glycoside icariin (1) has been accomplished in eleven steps with 7% overall yield from kaempferol. The 4'-OH methylation of kaempferol, the 8-prenylation of 3-O-methoxymethyl-4'-O-methyl-5-O-prenyl-7-O-benzylkaempferol (8) via para-Claisen-Cope rearrangement catalyzed by Eu(fod)3 in the presence of NaHCO3, and the glycosylation of icaritin (3) are the key steps. ...[more]

PMID: 26425179

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