Bisindole alkaloids from Alstonia

Ku W-F, Tan S-J, Low Y-Y, Komiyama K, Kam T-S. Angustilobine and andiangi-nine type inole alkaloids and an uleine-secovaUesamine bisindole alkaloid from Alstonia angustiloba. Phytochemistry 2011 72(2011) 2212-8. 

Tan SJ, Lim KH, Subramanian G, Kam TS. Macroline-sarpagine and macroline-pleiocarpamine bisindole alkaloids from Alstonia angustifoUa. Phytochemistry 2013 85 194-202. 

The bisindole alkaloids alstomacrophylline 108 and alstomacroline 109 have been isolated from the root bark of Alstonia macrophylla along with the monomeric indole alkaloid 20- f-antirhine <1997P757>. A dimeric indole alkaloid, schischkiniin 110, was isolated from the seeds of Centaurea schischkinii <2005T9001>. 

Certain Alstonia species of the family Apocynaceae contain bisindole alkaloids of interesting construction. These are (+)-villalstonine from Alstonia macro-phylla Wall., A. muelleriana, A. somersetensis F.M. Bailey and A. villosa Blume, (+ )-macralstonine from A. macrophylla Wall., and macralstonidine from A. macrophylla Wall, and A. somersetensis F.M. Bailey. A common unit of all three dimers is the monomeric indolic base macroline. 

When NMR and mass spectrometry became available, a large number of alkaloids from various apocynaceous plants were investigated (e.g. species of the genera Alstonia, Aspidosperma, Conopharyngia, Gabunia, Hunteria, Iboga, Oncinotis, Rauwolfia, Vinca). Villalstonine was the first bisindole alkaloid whose structure was elucidated by mass spectral analysis. 

Perhentidines A (189) and B (190) were bisindole alkaloids consisting of macrohne with an opened E ring and macrohne units. They were isolated from the stem bark of Malaysian Alstonia macrophylla (Apocynaceae) together with two known bisindole alkaloids, perhentinine (191) and macralstonine (192) (Figure 36). Perhentidines A (189) and B (190) are a pair of C-20... 

Four macroline—vobasine-type bisindole alkaloids, perhentisines A—C (201—203) and lumutinine E (204), were isolated from the stem bark of Malaysian Alstonia angustifolia (Apocynaceae). In addition, bisindole... 

Alstonia sphaerocapitata and A. undulata provided undulatine (315) and deformylundulatine (316), respectively (213(214). The alkaloids are constituted from the union of a cabucraline unit and a N-methylpericyclivine unit, via C(10) of the former to C(6 ) of the latter. The structures were elucidated on the basis of mass spectral and NMR data (213). An undulatine-type bisindole 317 has been prepared via acid-mediated coupling of a pericyclivine derivative 318 with the electron-rich cabucraline (319) (215). 

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