title: Convergent synthesis of pyragonicin.
abstract: This paper describes a second-generation synthesis of an antitumor tetrahydropyran (THP) acetogenin, pyragonicin. The key step involved an olefin cross-metathesis between the THP segment and the terminal gamma-lactone residue. The coupling reaction in the presence of Grubbs' second-generation catalyst resulted in an unseparable mixture of a desired coupling product and its one-carbon eliminated product while the use of Grubbs' first-generation catalyst afforded the former exclusively. A novel MOM-migrating reaction found in a cyclization reaction is also discussed.
authors.affiliation: RIKEN (The Institute of Physical and Chemical Research), Wako-shi, Saitama, 351-0198, Japan. shunyat@riken.go.jp
authors.forename: Shunya
authors.initials: S
authors.lastname: Takahashi
authors.forename: Yayoi
authors.initials: Y
authors.lastname: Hongo
authors.forename: Narihito
authors.initials: N
authors.lastname: Ogawa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Koshino
authors.forename: Tadashi
authors.initials: T
authors.lastname: Nakata
mesh_terms: D005233:Fatty Alcohols / Q000138:chemical synthesis* / Q000737:chemistry; D007783:Lactones / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure
chemical_list: D005233:Fatty Alcohols; D007783:Lactones; C509193:pyragonicin