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(+)-Zwittermicin A. Rapid assembly of C9-C15 and a formal total synthesis.

ABSTRACT: A short, enantioselective synthesis of the C9-C15 portion of (+)-zwittermicin A is reported that exploits directional functionalization of the known hepta-2,5-diyne-1,7-diol by partial reduction of the two triple bonds followed by Sharpless asymmetric epoxidation and boron-directed double ring-opening with sodium azide under Miyashita conditions. Subsequent desymmetrization of the C(2)-symmetric diazidotetraol product converges upon (-)-3--the enantiomer of the key intermediate of our earlier structural proof and synthesis of (-)-zwittermicin A--and constitutes a formal synthesis of (+)-zwitttermicin A.

SUBMITTER: Rogers EW

PROVIDER: S-EPMC2759841 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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(+)-Zwittermicin A. Rapid assembly of C9-C15 and a formal total synthesis.

Rogers Evan W EW Molinski Tadeusz F TF

The Journal of organic chemistry 20091001 20

A short, enantioselective synthesis of the C9-C15 portion of (+)-zwittermicin A is reported that exploits directional functionalization of the known hepta-2,5-diyne-1,7-diol by partial reduction of the two triple bonds followed by Sharpless asymmetric epoxidation and boron-directed double ring-opening with sodium azide under Miyashita conditions. Subsequent desymmetrization of the C(2)-symmetric diazidotetraol product converges upon (-)-3--the enantiomer of the key intermediate of our earlier st ...[more]

PMID: 19746943

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