Strychnos bisindole

Fig.(8) Structure of Strychnos bisindole alkaloids evaluated for their anticancer and/or antiprotozoal activities.

Bisleucocurine A (144). the first example of a Strychnos—Strychnos bisindole alkaloid with N-1—C-17 and C-12—C-2 double linkages, was isolated from the leaves of Leuconotis griffithii (Apocynaceae), together with... 

On the basis of structure the dimers can be clearly divided into two groups. The first is comprised of alkaloids with identical or very closely related components in which the same centres act as linkage positions. The Calycanthaceous and Calabash-curare-South American Strychnos alkaloids make up this group. The second group consists of dimeric bases in which the alkaloid components are of a different structural type (e.g. geissospermine, vinblastine, and tubulosine) or in which two similar halves are linked unsymmetrically through two different centres e.g. macralstonine). The bisindole alkaloids will be discussed in this order. ... 

Introduction and Interrelationships.—Calabash-curare is prepared from the bark of South American Strychnos of the family Loganiaceae. From the curare and the Strychnos species, along with a large number of monomeric indole alkaloids, fifteen structurally classified bisindole alkaloids have been isolated. Their structures are all based on one CjgN skeleton. Only the N h N h fdimetho-salts exhibit high curare-activity. 

The complete stereostructure of divarine (27), a new bisindole alkaloid from Strychnos divaricans has been determined, by use of 2D NMR techniques [88]. 

Two types of Strychnos alkaloids have been evaluated for their potential as anticancer drugs. These include the monoindole alkaloids whose structure comprises a harmane skeleton 34, Fig. (7) and the bisindole alkaloids of S. usambarensis, Fig. (8). 

Jonville MC, Dive G, Angenot L, Bero J, Tits M, Ollivier E, et al. Dimeric bisindole alkaloids from the stem bark of Strychnos nux-vomica L. Phytochemistry 2013 87 157 3. 

Divaricine. Mukherjee et al. (1991) reported the elucidation of the structure of divaricine (22), a new bisindole from Strychnos divaricans. Again, HMQC... 

Mukherjee R, da Silva BA, Das BC, Keifer PA, Shoolery IN (1991) Structure and stereochemistry of divaricine, a new bisindole alkaloid from Strychnos divaricans Ducke. Heterocycles 32 985-990... 

An arrow poison from a blowgun is often used by native peoples of South America for hunting. Three kinds of poisons are known (as explained in Chapter 1.5 and Chapter 2.15). The toxic constituents from these poisons are alkaloids, including J-tubocurarine (J-Tc),a bisbenzylisoquinoline alkaloid, and C-curarine, a bisindole alkaloid in the Strychnos series. Deca-methonium (Chapter 1.5), a synthetic compound based on the chemical structure of d-Tc, was formerly used as a muscle relaxant in surgery. 

Curares from Strychnos Species Olivacine and Ellipticine Bisindole Alkaloids Catharanthus Alkaloids Gelsemium Alkaloids Alkaloids from Tabernanthe iboga Camptothecine Biogenesis... 

Numerous bisindole alkaloids, formed by dimerization of monomeric monoterpenoid-derived indoles, have been isolated. Probably the best source of these alkaloids is Cathara-nthus roseus bisindole alkaloids from this source have been tabulated (Blasko and Cordell, 1990). Several of these alkaloids antitumor activity (Blasko and Cordell, 1988) most important in this regard are vincristine (55) and vinblastine (56) from Catharanthus roseus (Fig. 34.15). Certain other dimeric indole alkaloids known as curares have paralytic effects in animals (see the subsection Curares from Strychnos species, above). 

A.T. Tchina, A. Jansen, J.-N. Nyemb, M. Tits, G. Dive, L. Angenot, M. Frederich, StrychnobaiUonine, an unsymmetrical bisindole alkaloid with an unprecedented skeleton from Strychnos icaja roots, J. Nat. Prod. 77 (2014) 1078-1082. 

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