title: Synthesis of a C(1)-C(23) fragment for spirastrellolide E: development of a mechanistic rationale for spiroketalization.
abstract: Synthetic analysis of spirastrellolide E envisioned to entail a cross-metathesis union of the northern and southern hemispheres followed by a Sharpless epoxidation/methylation sequence to achieve the C(22,23) stereogenicity leads to the design of a C(1)-C(23) advanced southern hemisphere exploiting a gold-catalyzed directed spiroketalization as a key step. Stereochemical analysis of this strategic transformation provides insight on the impact of the directing group carbinol stereogenicity on the reaction efficiency and, in turn, permits the conversion of the minor isomer of the spiroketal precursor to the requisite congener for successful spiroketalization.
authors.affiliation: Department of Chemistry, Laboratory for Research on the Structure of Matter and Monell Chemical Senses Center, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
authors.forename: Alexander
authors.initials: A
authors.lastname: Sokolsky
authors.affiliation: Department of Chemistry, Laboratory for Research on the Structure of Matter and Monell Chemical Senses Center, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
authors.forename: Martin
authors.initials: M
authors.lastname: Cattoen
authors.affiliation: Department of Chemistry, Laboratory for Research on the Structure of Matter and Monell Chemical Senses Center, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
authors.forename: Amos B
authors.initials: AB
authors.lastname: Smith
mesh_terms: D018942:Macrolides / Q000138:chemical synthesis* / Q000737:chemistry; D008968:Molecular Conformation; D013141:Spiro Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D018942:Macrolides; D013141:Spiro Compounds
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