Alkaloids of the Annonaceae. Part 33. Annomontine and methoxyannomontine, two new pyrimidine-β-carboline-type alkaloids from Annona montana

Two new alkaloids, which we have named annomontine (1) and methoxyannomontine (2), have been isolated from the trunk- and root-barks of Annona montana Macf. (Annonaceae). Their structures have been deduced by spectral analysis and confirmed by an X-ray structure determination of (2). They are the first members of the new class of 1-(2′-aminopyrimidin-4-yl)-β-carboline alkaloids.