Convergent synthesis of pyragonicin.
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.
Takahashi
Shunya
S
RIKEN (The Institute of Physical and Chemical Research), Wako-shi, Saitama, 351-0198, Japan. shunyat@riken.go.jp
Hongo
Yayoi
Y
Ogawa
Narihito
N
Koshino
Hiroyuki
H
Nakata
Tadashi
T
D005233:Fatty Alcohols / Q000138:chemical synthesis* / Q000737:chemistry; D007783:Lactones / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure
D005233:Fatty Alcohols; D007783:Lactones; C509193:pyragonicin