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Stereoselective synthesis of acortatarins A and B.

ABSTRACT: Acortatarins A and B have been synthesized via stereoselective spirocyclizations of glycals. Mercury-mediated spirocyclization of a pyrrole monoalcohol side chain leads to acortatarin A. Glycal epoxidation and reductive spirocyclization of a pyrrole dialdehyde side chain leads to acortatarin B. Acid equilibration and crystallographic analysis indicate that acortatarin B is a contrathermodynamic spiroketal with distinct ring conformations compared to acortatarin A.

SUBMITTER: Wurst JM

PROVIDER: S-EPMC3466107 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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Stereoselective synthesis of acortatarins A and B.

Wurst Jacqueline M JM Verano Alyssa L AL Tan Derek S DS

Organic letters 20120827 17

Acortatarins A and B have been synthesized via stereoselective spirocyclizations of glycals. Mercury-mediated spirocyclization of a pyrrole monoalcohol side chain leads to acortatarin A. Glycal epoxidation and reductive spirocyclization of a pyrrole dialdehyde side chain leads to acortatarin B. Acid equilibration and crystallographic analysis indicate that acortatarin B is a contrathermodynamic spiroketal with distinct ring conformations compared to acortatarin A. ...[more]

PMID: 22924668

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