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Toward the Synthesis of Antascomicin B. Synthesis of a Model of the C22-C34 Fragment via Ireland-Claisen and Allylic Diazene Rearrangements.

ABSTRACT: The C22-C34 fragment of antascomicin B lacking the C31 and C32 hydroxyl groups has been prepared in 11 steps from commercially available 2-OH-cyclohexanone. An Ireland-Claisen rearrangement was employed to install the C26 and C27 stereocenters. Our recently reported diastereoselective acyclic 1,3-reductive transposition was used to establish the remote C23 stereocenter. Directed hydrogenation was employed to set the C29 stereocenter. The model compound contains 5 of the stereocenters and all of the carbons of the corresponding fragment of antascomicin B.

SUBMITTER: Qi W

PROVIDER: S-EPMC2614681 | biostudies-literature | 2008

REPOSITORIES: biostudies-literature

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Toward the Synthesis of Antascomicin B. Synthesis of a Model of the C22-C34 Fragment via Ireland-Claisen and Allylic Diazene Rearrangements.

Qi Wei W McIntosh Matthias C MC

Tetrahedron 20080101 29

The C22-C34 fragment of antascomicin B lacking the C31 and C32 hydroxyl groups has been prepared in 11 steps from commercially available 2-OH-cyclohexanone. An Ireland-Claisen rearrangement was employed to install the C26 and C27 stereocenters. Our recently reported diastereoselective acyclic 1,3-reductive transposition was used to establish the remote C23 stereocenter. Directed hydrogenation was employed to set the C29 stereocenter. The model compound contains 5 of the stereocenters and all of ...[more]

PMID: 19132139

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