title: Construction of AB-ring system of taxane framework by A-ring annulation strategy: synthesis of 1-hydroxy-8,11,11-trimethylbicyclo-[5.3.1]undec-7-en-9-one by way of intramolecular aldol cyclization to form the C1-C10 bond.
abstract: Construction of the AB-ring system of the taxane framework via an A-ring annulation strategy was demonstrated by base-mediated intramolecular aldol reaction of (Z)-2,2-dimethyl-3-(1-methyl-2-oxopropylidene)cyclooctanone, affording the title compound, 1-hydroxy-8,11,11-trimethylbicyclo[5.3.1]undec-7-en-9-one. A cyclization precursor, the tetra-substituted (Z)-alkene, was prepared from the corresponding cyclooctanone derivative, 3-[(alpha,alpha- dimethylbenzyl)dimethylsiloxy]-2,2-dimethylcyclooctanone via a bicyclic alpha,beta-unsaturated lactone intermediate.
authors.affiliation: Department of Applied Chemistry, Faculty of Science, Science University of Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yamada
authors.forename: H
authors.initials: H
authors.lastname: Iwadare
authors.forename: T
authors.initials: T
authors.lastname: Mukaiyama
mesh_terms: D001643:Bridged Bicyclo Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D001952:Bridged-Ring Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D034242:Cyclooctanes; D004224:Diterpenes / Q000138:chemical synthesis* / Q000737:chemistry; D007659:Ketones / Q000737:chemistry; D007783:Lactones / Q000138:chemical synthesis / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D013237:Stereoisomerism; D043823:Taxoids
chemical_list: C110554:1-hydroxy-8,11,11-trimethylbicyclo(5.3.1)undec-7-en-9-one; D001643:Bridged Bicyclo Compounds; D001952:Bridged-Ring Compounds; D034242:Cyclooctanes; D004224:Diterpenes; D007659:Ketones; D007783:Lactones; D043823:Taxoids; C080625:taxane; C044494:cyclooctanone