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Assignment and stereocontrol of hibarimicin atropoisomers.

ABSTRACT: A stereochemical feature of the hibarimicins is a central biaryl (HMP-Y6) or aryl-quinone (hibarimicinone) incorporated as a single atropodiastereomer. Herein, a chiral resolution and deracemization process to access optically enriched biaryls aR-3 and aS-3 is described. From these atropoenantiomers the BCD-EFG ring system of HMP-Y6 is constructed [(+)-aR-7]. Comparison of CD spectra of aR-7 to HMP-Y6 leads to the assignment of HMP-Y6 and hibarimicin B atropoisomers as aR and aS, respectively.

SUBMITTER: Romaine IM

PROVIDER: S-EPMC3163008 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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Assignment and stereocontrol of hibarimicin atropoisomers.

Romaine Ian M IM Hempel Jonathan E JE Shanmugam Ganesh G Hori Hiroshi H Igarashi Yasuhiro Y Polavarapu Prasad L PL Sulikowski Gary A GA

Organic letters 20110803 17

A stereochemical feature of the hibarimicins is a central biaryl (HMP-Y6) or aryl-quinone (hibarimicinone) incorporated as a single atropodiastereomer. Herein, a chiral resolution and deracemization process to access optically enriched biaryls aR-3 and aS-3 is described. From these atropoenantiomers the BCD-EFG ring system of HMP-Y6 is constructed [(+)-aR-7]. Comparison of CD spectra of aR-7 to HMP-Y6 leads to the assignment of HMP-Y6 and hibarimicin B atropoisomers as aR and aS, respectively. ...[more]

PMID: 21812391

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