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Studies on the mechanism of action of prekinamycin, a member of the diazoparaquinone family of natural products: evidence for both sp2 radical and orthoquinonemethide intermediates.

ABSTRACT: The putative reductive activation chemistry of the diazoparaquinone antibiotics was modeled with Bu(3)Sn-H and prekinamycin dimethyl ether along with prekinamycin itself. Reaction in various combinations of aromatic solvents, with and without the nucleophile benzylmercaptan present, led to isolation of both radical-trapping arene adducts and nucleophilic capture benzyl thioether products. On the basis of these product distribution studies, the intermediacies of, first, a cyclopentenyl radical and, next, an orthoquinonemethide electrophile are postulated.

SUBMITTER: Feldman KS

PROVIDER: S-EPMC2515591 | biostudies-literature | 2006 Sep

REPOSITORIES: biostudies-literature

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Studies on the mechanism of action of prekinamycin, a member of the diazoparaquinone family of natural products: evidence for both sp2 radical and orthoquinonemethide intermediates.

Feldman Ken S KS Eastman Kyle J KJ

Journal of the American Chemical Society 20060901 38

The putative reductive activation chemistry of the diazoparaquinone antibiotics was modeled with Bu(3)Sn-H and prekinamycin dimethyl ether along with prekinamycin itself. Reaction in various combinations of aromatic solvents, with and without the nucleophile benzylmercaptan present, led to isolation of both radical-trapping arene adducts and nucleophilic capture benzyl thioether products. On the basis of these product distribution studies, the intermediacies of, first, a cyclopentenyl radical an ...[more]

PMID: 16984207

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