title: Syntheses of (+)-30-epi-, (-)-6-epi-, (±)-6,30-epi-13,14-Didehydroxyisogarcinol and (±)-6,30-epi-Garcimultiflorone A Utilizing Highly Diastereoselective, Lewis Acid-Controlled Cyclizations.
abstract: The first syntheses of 13,14-didehydroxyisogarcinol (6) and garcimultiflorone A (5) stereoisomers are reported in six steps from a commercially available phloroglucinol. Lewis acid-controlled, diastereoselective cationic oxycyclizations enabled asymmetric syntheses of (-)-6-epi-6 and (+)-30-epi-6. A similar strategy enabled production of the meso-dervied isomers (±)-6,30-epi-6 and (±)-6,30-epi-5. Finally, a convenient strategy for gram scale synthesis was developed utilizing diastereomer separation at a later stage in the synthesis that minimized the number of necessary synthetic operations to access all possible stereoisomers.
authors.affiliation: Department of Chemistry, Center for Molecular Discovery (BU-CMD), Boston University , 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States.
authors.forename: Jonathan H
authors.initials: JH
authors.lastname: Boyce
authors.affiliation: Department of Chemistry, Center for Molecular Discovery (BU-CMD), Boston University , 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States.
authors.forename: Vincent
authors.initials: V
authors.lastname: Eschenbrenner-Lux
authors.affiliation: Department of Chemistry, Center for Molecular Discovery (BU-CMD), Boston University , 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States.
authors.forename: John A
authors.initials: JA
authors.lastname: Porco
mesh_terms: D003500:Cyclization; D058116:Lewis Acids / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D058116:Lewis Acids