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Unconventional application of the Mitsunobu reaction: Selective flavonolignan dehydration yielding hydnocarpins.

ABSTRACT: Various Mitsunobu conditions were investigated for a series of flavonolignans (silybin A, silybin B, isosilybin A, and silychristin A) to achieve either selective esterification in position C-23 or dehydration in a one-pot reaction yielding the biologically important enantiomers of hydnocarpin D, hydnocarpin and isohydnocarpin, respectively. This represents the only one-pot semi-synthetic method to access these flavonolignans in high yields.

SUBMITTER: Huang G

PROVIDER: S-EPMC4901995 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Unconventional application of the Mitsunobu reaction: Selective flavonolignan dehydration yielding hydnocarpins.

Huang Guozheng G Schramm Simon S Heilmann Jörg J Biedermann David D Křen Vladimír V Decker Michael M

Beilstein journal of organic chemistry 20160408

Various Mitsunobu conditions were investigated for a series of flavonolignans (silybin A, silybin B, isosilybin A, and silychristin A) to achieve either selective esterification in position C-23 or dehydration in a one-pot reaction yielding the biologically important enantiomers of hydnocarpin D, hydnocarpin and isohydnocarpin, respectively. This represents the only one-pot semi-synthetic method to access these flavonolignans in high yields. ...[more]

PMID: 27340458

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