Two Dibenzopyrrocoline Alkaloids from Litsea cubeba

Further investigation of quaternary alkaloids from Litsea cubeba led to the isolation of two novel dibenzopyrrocoline alkaloids, (−)-litcubine (1) and (−)-litcubinine (2). Their structures and 7R,13S stereochemistry were elucidated by spectral analysis and chemical correlation. Including these two, only six dibenzopyrrocoline alkaloids have been isolated from natural sources.