Author/Authors :
Michiharu Kato، نويسنده , , Hiroshi Kosugi، نويسنده , , Tsuyoshi Ichiyanagi، نويسنده , , Hisahiro Hagiwara، نويسنده , , Ariko Kodaira، نويسنده , , Takashi Kusakari، نويسنده , , Takao Suzuki، نويسنده , , Minako Ando، نويسنده , , Jasmine Lee، نويسنده , , Peter Drechsel، نويسنده , , Bernhard Vogler، نويسنده ,
Abstract :
Using (1S,5S)-(−)-verbenone (8b), readily obtainable from (+)-nopinone (3), as the chiral source, we have established the general method for preparation of three kinds of key intermediates, conjugate enones 9 and 10 for the syntheses of neo-trans-clerodanes and 11 for those of neo-cis-clerodanes. Starting with the compound 10, the first enantioselective syntheses of (−)-(5R,8S,9S,10R)-7-oxo-cleroda-3,13E-dien-15-oic acid (7-oxo-kolavenic acid) (1) and solidagonic acid (2) as its methyl ester (48) were achieved.
Keywords :
Natural products , ene reactions , cleavage reactions , Asymmetric synthesis
