title: Total synthesis of methyl sarcophytoate, a marine natural biscembranoid.
abstract: The total synthesis of methyl sarcophytoate (1), a marine natural biscembranoid, has been achieved by the thermal Diels-Alder reaction between the 14-membered dienophile unit, methyl sarcoate (2), and the 14-membered diene unit 64. Methyl sarcoate (2) was prepared using n-BuLi-Bu(2)Mg-mediated dithiane coupling, Kosugi-Migita-Stille coupling, and Grubbs ring-closing metathesis. The diene unit 64 was prepared using Sharpless asymmetric epoxidation, Grubbs ring-closing metathesis, 6-exo-tet epoxide opening, and n-BuLi-Bu(2)Mg-mediated Ito-Kodama cyclization. The final Diels-Alder reaction between 2 and 64 proceeded with high site, endo/exo, pi-face, and regioselectivities. During this reaction, partial E --> Z isomerization at the C4 position was observed.
authors.affiliation: Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Ichige
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Okano
authors.forename: Naoki
authors.initials: N
authors.lastname: Kanoh
authors.forename: Masaya
authors.initials: M
authors.lastname: Nakata
mesh_terms: D000818:Animals; D037421:Anthozoa; D004224:Diterpenes / Q000138:chemical synthesis* / Q000737:chemistry; D008968:Molecular Conformation; D013237:Stereoisomerism; D013729:Terpenes / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D004224:Diterpenes; D013729:Terpenes; C535000:methyl sarcophytoate