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Stereoselective Syntheses of all the Possible Stereoisomers of Coronafacic Acid.

ABSTRACT: An efficient and stereoselective syntheses of all the possible stereoisomers of coronafacic acid (CFA) has been developed. The stereochemistries of C3a and C7a were controlled in a diastereoselective Diels-Alder type cycloaddition using a chiral auxiliary. CFA and 6-epi-CFA were synthesized by hydrogenation of a common intermediate. During the synthesis of 6-epi-CFA, we established that its cis-fused configuration is important for the introduction of C4-C5 double bond by dehydration. This report is the first practical synthesis of both 6-epi-CFA, and its enantiomer.

SUBMITTER: Watanabe R

PROVIDER: S-EPMC7545439 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Stereoselective Syntheses of all the Possible Stereoisomers of Coronafacic Acid.

Watanabe Raku R Kato Nobuki N Hayashi Kengo K Tozawa Sho S Ogura Yusuke Y Kuwahara Shigefumi S Ueda Minoru M

ChemistryOpen 20201009 10

An efficient and stereoselective syntheses of all the possible stereoisomers of coronafacic acid (CFA) has been developed. The stereochemistries of C3a and C7a were controlled in a diastereoselective Diels-Alder type cycloaddition using a chiral auxiliary. CFA and 6-epi-CFA were synthesized by hydrogenation of a common intermediate. During the synthesis of 6-epi-CFA, we established that its cis-fused configuration is important for the introduction of C4-C5 double bond by deh ...[more]

PMID: 33072470

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