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Enantioselective Total Synthesis of Nigelladine A via Late-Stage C-H Oxidation Enabled by an Engineered P450 Enzyme.

ABSTRACT: An enantioselective total synthesis of the norditerpenoid alkaloid nigelladine A is described. Strategically, the synthesis relies on a late-stage C-H oxidation of an advanced intermediate. While traditional chemical methods failed to deliver the desired outcome, an engineered cytochrome P450 enzyme was employed to effect a chemo- and regioselective allylic C-H oxidation in the presence of four oxidizable positions. The enzyme variant was readily identified from a focused library of three enzymes, allowing for completion of the synthesis without the need for extensive screening.

SUBMITTER: Loskot SA

PROVIDER: S-EPMC5679227 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Enantioselective Total Synthesis of Nigelladine A via Late-Stage C-H Oxidation Enabled by an Engineered P450 Enzyme.

Loskot Steven A SA Romney David K DK Arnold Frances H FH Stoltz Brian M BM

Journal of the American Chemical Society 20170724 30

An enantioselective total synthesis of the norditerpenoid alkaloid nigelladine A is described. Strategically, the synthesis relies on a late-stage C-H oxidation of an advanced intermediate. While traditional chemical methods failed to deliver the desired outcome, an engineered cytochrome P450 enzyme was employed to effect a chemo- and regioselective allylic C-H oxidation in the presence of four oxidizable positions. The enzyme variant was readily identified from a focused library of three enzyme ...[more]

PMID: 28721734

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