title: Total Synthesis and Structural Revision of the Cytotoxin Aruncin B.
abstract: The sodium salts E-15 and Z-15 of the originally proposed dihydropyran acid structure of aruncin B (1) were prepared through ring-closing alkene metathesis (RCM) and ethoxyselenation-selenoxide elimination, but acid sensitivity of these salts, together with inconsistencies in the spectral data, suggested a significant structural misassignment. A β-iodo Morita-Baylis-Hillman reaction to give Z-iodo ester 24, followed by Sonogashira cross-coupling-5-exo-dig lactonization, provided concise access to a Z-γ-alkylidenebutenolide 18, which possessed data corresponding to those originally reported for aruncin B.
authors.affiliation: Department of Chemistry, Chemistry Research Laboratory, University of Oxford , Mansfield Road, Oxford OX1 3TA, U.K.
authors.forename: Aubert
authors.initials: A
authors.lastname: Ribaucourt
authors.affiliation: Department of Chemistry, Chemistry Research Laboratory, University of Oxford , Mansfield Road, Oxford OX1 3TA, U.K.
authors.forename: David M
authors.initials: DM
authors.lastname: Hodgson
mesh_terms: D015394:Molecular Structure; D011714:Pyrans / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: C574448:2-(8'-ethoxy-8'-methylpropylidene)-5-hydroxy-3,6-dihydro-2H-pyran-4-carboxylic acid; D011714:Pyrans