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P450-Mediated Coupling of Indole Fragments To Forge Communesin and Unnatural Isomers.

ABSTRACT: Dimeric indole alkaloids are structurally diverse natural products that have attracted significant attention from the synthetic and biosynthetic communities. Here, we describe the characterization of a P450 monooxygenase CnsC from Penicillium that catalyzes the heterodimeric coupling between two different indole moieties, tryptamine and aurantioclavine, to construct vicinal quaternary stereocenters and yield the heptacyclic communesin scaffold. We show, via biochemical characterization, substrate analogues, and computational methods that CnsC catalyzes the C3-C3' carbon-carbon bond formation and controls the regioselectivities of the pair of subsequent aminal bond formations to yield the communesin core. Use of ?-N-methyltryptamine and tryptophol in place of tryptamine led to the enzymatic synthesis of isocommunesin compounds, which have not been isolated to date.

SUBMITTER: Lin HC

PROVIDER: S-EPMC4988905 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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P450-Mediated Coupling of Indole Fragments To Forge Communesin and Unnatural Isomers.

Lin Hsiao-Ching HC McMahon Travis C TC Patel Ashay A Corsello Michael M Simon Adam A Xu Wei W Zhao Muxun M Houk K N KN Garg Neil K NK Tang Yi Y

Journal of the American Chemical Society 20160318 12

Dimeric indole alkaloids are structurally diverse natural products that have attracted significant attention from the synthetic and biosynthetic communities. Here, we describe the characterization of a P450 monooxygenase CnsC from Penicillium that catalyzes the heterodimeric coupling between two different indole moieties, tryptamine and aurantioclavine, to construct vicinal quaternary stereocenters and yield the heptacyclic communesin scaffold. We show, via biochemical characterization, substrat ...[more]

PMID: 26963294

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