Sceletium tortuosum

This type of action is found in kanna, or Sceletium expansum and Sceletium tortuosum (Aizoaceae), which have been used by South African shamans from prehistoric times to enhance animal spirits, sparkle the eyes, and to stimulate gaiety. The active constituent of kanna is a serotonin-like alkaloid called mesembrine, which is a potent serotonin re-uptake inhibitor—hence, some potential for the treatment of anxiety and depression however, careful clinical trials must be performed. 

The mood elevating properties of Sceletium tortuosum have been attributed to mesembrine [9], an alkaloid with potent selective serototun (5-HT) re-uptake inhibition activity 86). Other sceletium alkaloids as they are now referred to are mesembrenone, mesembrenol and tortuosamine. The use of mesembrine-type alkaloids was patented 92). Selective serotoiun (5-HT) re-uptake inhibitors (SSRls), like mesembrine, have become important treatments in the therapeutic management of depression 93). Several southern African medicinal plants, in particular Amaryllidaceae, have shown in vitro affinity for serotoiun re-uptake transporters 94,95). Several active alkaloids have been identified from Boophone and Crinum species 95, 96). 

Sceletium strictum (mesembrine), 364 Sceletium tortuosum (mesembrine),... 

Mesembrine, mesembrenone, mesembrenone, mesembranol, epimesembranol Sceletium tortuosum tablets CZE 50 mM phosphate, pH 1.5 UV at 228 ran [15]... 

Using the Shi epoxidation method, Taber and He demonstrated an elegant synthesis of (—)-mesembrine, a very active serotonin reuptake inhibitor isolated from Sceletium tortuosum (Scheme 35.18). Shi epoxidation of olefin 69 with ketone 62 followed by ring opening of the resulting crude epoxide with allylmagnesium chloride provided compound 70 in 73% yield and 96% ee. Alcohol 70 was then converted into ( )-mesembiine 72 in five steps. ... 

Mesembrine (-)-Mesembrine (12) is an octahydroindole alkaloid isolated from certain plants of the Sceletium genus, namely S. namaquense, S. strictum and S. tortuosum The mesembrine sttucture has been established as 12. Mesembrine was synthesized from noncarbohydrate, and its synthesis from D-mannitol has been presented herein. 

Sceletium Alkaloids.—Full details of an earlier briefly reported synthesis of ( )-mesembrine (3) have been published and a new synthesis has been described. The latter is outlined in Scheme 1 A new Sceletium alkaloid has been isolated from S. namaquense. It has been formulated as (4) on spectral evidence, the assignment of structure being confirmed by direct spectral comparison between the natural base and racemic (4), synthesized earlier. Channaine, another alkaloid of this family, from S. tortuosum, has structure (5) on the basis of an X-ray diffraction analysis of its hexahydrate. It may be an artefact arising from the condensation of a pair of iV-desmethylmesembrenone molecules (6) during isolation. ... 

There is one report in which mesembrine, mesembranol, and Sceletium alkaloid A4 are reported to occur as the partial racemates in S. tortuosum (17). 

An independent report (39) has indicated that Sceletium alkaloid A4 occurs as the partial racemate in S. tortuosum. 

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