Calycanthus alkaloids

These alkaloids are not of monoterpenoid origin, and it is considered that two molecules of Ab-methyl-tryptamine dimerize oxidatively to give chimonanthine or calycanthine. 

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Many alkaloids contain an indole nucleus as a part of their structure. Monoterpene-derived indole alkaloids see Chapter 34) are the most important of these compounds, but several other significant types of indole alkaloids exist. Ergot alkaloids formed from tryptamine and a mevalonate-derived hemiterpene unit are of medical importance. Others, such as harmane alkaloids, physostigmine and a series of structurally similar alkaloids, Calycanthus alkaloids (Calycanthaceae) and related compounds (principally from the Rubiaceae), and relatively minor types of alkaloids from the Ascelpiada-... 

Note to Table 87 As a supplement, other work may be mentioned in which TLC has been a useful, indeed indispensable, help on the animal poisons, taricha- and tetrodotoxine [139b] the lycopodium alkaloid L 9 [10, 49b] anuloline [209b] and the biosynthesis of the calycanthus alkaloid, calicanthine [210b]. 

Following earlier reports of the presence of toxic alkaloids in the seeds of Calycanthus glaucus Willd., the isolation and characterization of calycanthine was recorded by Gordin (1). A later attempt by the same author (2) to obtain more calycanthine from the same presumed botanical source led to the isolation of what was assumed to be an isomeric base,... 

Calycanthine (1).—The alkaloid occurs in both genera of Calycanthaceae, namely Calycanthus L. and Chimonanthus Lindl. Meratia Loisel). Although this base does not possess an indole skeleton, the elucidation of its structure and in particular Robinson s biogenetic proposals which ultimately led to its structure, were of such importance with respect to the rest of this group that its inclusion here is a necessity. The structural work on calycanthine began at a time when... 

This alkaloid, isolated from various species of Calycanthus, is a convul-sant poison in warm-blooded animals. Calycanthine (1 40,000) greatly increases the tonus and movements of the isolated rabbit uterus. The isolated guinea pig uterus, however, shows only a feeble response to concentrations of 1 10,000 (173). 

Alkaloid from various species of Calycanthus Oryst, from. MejCO.Aq. M.p. 219-20, anhyd. 246 Soda-lime dist. — N-methyl-trjmtamine. P + HI —> quinoline Phenylcarbamyl deriv. m.p., 252°... 

Alkaloids from tryptophan can be classified into two groups. One of them is a small and simple group to which belong the calycanthus, canthinone, and )8-car-boline alkaloids the other is the monoterpenoid indole alkaloids. 

Eiter K, Svierak O 1951 Folicanthine, a new alkaloid from the leaves of Calycanthus floridus. Monatschrift 82 186-188... 

While phenyl pyrrole derivatives have not been isolated from higher plants, a number of plant alkaloids have been shown to be derived from tryptophan (Manske, 1965). Several of these plants, such as the calabar bean (Physostigma venenosum Balf.) and the family Calycanthaceae [Calycanthus L. and Chimonanthus Lindl.), yield compounds, e.g. physostigmine (VIII) and folicanthine (IX) whose biosynthesis may follow a pathway similar to that of pyrrolnitrin. 

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