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Formal syntheses of naturally occurring welwitindolinones.

ABSTRACT: The formal syntheses of N-methylwelwitindolinone C isothiocyanate, N-methylwelwitindolinone C isonitrile, N-methylwelwitindolinone D isonitrile, 3-hydroxy-N-methylwelwitindolinone C isothiocyanate, and 3-hydroxy-N-methylwelwitindolinone C isonitrile are reported. The synthesis features several novel processes, including a Lewis acid mediated coupling between a benzylic-type heteroaromatic alcohol and a highly functionalized silyl ketene acetal, an intramolecular enolate arylation, and a regioselective, Pd(0)-catalyzed ?-allylic cyclization of a ?-benzoyloxy enone moiety that is revealed by unmasking a furan ring.

SUBMITTER: Fu TH

PROVIDER: S-EPMC3416027 | biostudies-other | 2012 Aug

REPOSITORIES: biostudies-other

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Formal syntheses of naturally occurring welwitindolinones.

Fu Tsung-hao TH McElroy William T WT Shamszad Mariam M Martin Stephen F SF

Organic letters 20120725 15

The formal syntheses of N-methylwelwitindolinone C isothiocyanate, N-methylwelwitindolinone C isonitrile, N-methylwelwitindolinone D isonitrile, 3-hydroxy-N-methylwelwitindolinone C isothiocyanate, and 3-hydroxy-N-methylwelwitindolinone C isonitrile are reported. The synthesis features several novel processes, including a Lewis acid mediated coupling between a benzylic-type heteroaromatic alcohol and a highly functionalized silyl ketene acetal, an intramolecular enolate arylation, and a regiosel ...[more]

PMID: 22830424

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