The first total syntheses of two cernuane-type Lycopodiumalkaloids, (-)-cernuine and (+)-cermizine D, were accomplished starting from (+)-citronellal. The syntheses involved organocatalytic alpha-amination to afford oxazolidinone, which is used for diastereoselective allylation, and asymmetric transfer aminoallylation followed by stereoselective construction of an aminal moiety as key steps.
syntheses of cernuane-type and quinolizidine-type Lycopodium alkaloids are described. A commonintermediate5 for the two types of alkaloids was assembled practically from (+)-citronellal via organocatalytic α-amination, followed by the construction of oxazolidinone that was used for diastereoselective allylation. Key compound 5 was converted into cermizine C (3), and this in turn was converted into senepodine