Stereoselective total syntheses of three Lycopodium alkaloids, (-)-magellanine, (+)-magellaninone, and (+)-paniculatine, based on two Pauson-Khand reactions.
The total syntheses of (-)-magellanine, (+)-magellaninone, and (+)-paniculatine were completed from diethyl l-tartrate via the common intermediate in a stereoselective manner. The crucial steps in these syntheses involved two intramolecular Pauson-Khand reactions of enynes: the first Pauson-Khand reaction constructed the bicyclo[4.3.0] carbon framework, the corresponding A and B rings of these alkaloids in a highly stereoselective manner, whereas the second Pauson-Khand reaction stereoselectively produced the bicyclo[3.3.0]skeleton, which could be converted into the C and D rings of the target natural products.
Kozaka
Takashi
T
Division of Pharmaceutical Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
Miyakoshi
Naoki
N
Mukai
Chisato
C
D006576:Heterocyclic Compounds, 4 or More Rings / Q000138:chemical synthesis* / Q000737:chemistry; D032502:Lycopodium / Q000737:chemistry*; D008968:Molecular Conformation; D013237:Stereoisomerism
D006576:Heterocyclic Compounds, 4 or More Rings; C527464:magellaninone; C527463:paniculatine; C471075:magellanine