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A novel ?,?-unsaturated nitrone-aryne [3+2] cycloaddition and its application in the synthesis of the cortistatin core.

ABSTRACT: We describe here a novel ?,?-unsaturated nitrone-aryne [3+2] cycloaddition. The resulting benzoisoxazolines underwent N-O bond reduction-elimination-electrocyclization sequence to furnish a variety of polysubstituted 2H or 2-alkylated-1-benzo-pyrans. The application of this methodology was further demonstrated in the synthesis of the oxa[3.2.1]octene moiety of cortistatin A.

SUBMITTER: Dai M

PROVIDER: S-EPMC2598426 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

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A novel α,β-unsaturated nitrone-aryne [3+2] cycloaddition and its application in the synthesis of the cortistatin core.

Dai Mingji M Wang Zhang Z Danishefsky Samuel J SJ

Tetrahedron letters 20081101 47

We describe here a novel α,β-unsaturated nitrone-aryne [3+2] cycloaddition. The resulting benzoisoxazolines underwent N-O bond reduction-elimination-electrocyclization sequence to furnish a variety of polysubstituted 2H or 2-alkylated-1-benzo-pyrans. The application of this methodology was further demonstrated in the synthesis of the oxa[3.2.1]octene moiety of cortistatin A. ...[more]

PMID: 19924220

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