Alkaloids of unknown constitution

The constitution of a number of alkaloids has not as yet been definitely established. Among these are aconitine from aconite, delphinine from larkspur, jervine and protojervine from veratrum viride, cevadine from sabadilla seed, lobeline from lobelia, the curare alkaloids from Chondro-dendron tomentosum, sanguinarine from sanguinaria, and many others. 

As with most attempts at chemical classification, some alkaloids do not fall satisfactorily into any of the preceding groups, and others can be classified under more than one group. 

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The two following alkaloids of unknown constitution have been recorded for Berberis and Mahonia species —... 

Salsoline and salsolidine (0-methylsalsoline) have been found by Orekhov and Proskurnina (32-35, 36, 37) in the desert plant Salsola arbuscula (S. richteri) belonging to the family Chenopodiaceae. A third alkaloid, of unknown constitution (salsamine), occurs in traces in the drug. 

The arbitrary classification of Rauwolfia alkaloids (91) is simplified here, and it is slightly different from a recent arrangement (92). The Rauwolfia alkaloids can all be regarded as yohimbinoid derivatives as shown in Chart I, viz. the yohimbines (all yohimbine isomers) 18-hydroxyyohimbines (reserpine-type alkaloids) ring E heterocycles and their anhydronium analogs (ajmalicine, serpentine) ajmaline-type (which includes sarpagine) and compounds of unknown constitution. 

These two bases, pleiomutine from Pleiocarpa mutica Benth. and umbellamine from Hunteria umbellata (K. Schum.) Hall. F. Carpodinus umbellatus K. Schum., Polyodoa umbellata Stapf., Picralima umbellata Stapf.), possess a common building block, namely 14,15-dihydroeburnamenine (229). This is bonded through C(14) to the aromatic ring of the second monomeric component, an indoline. Umbellamine is probably identical with the alkaloid hunterine, of unknown constitution, from Hunteria eburnea Pichon. ... 

These are jnuch more numerous than those which are volatile, and form the active principles of a great number of poisonous irlants. The classification adopted for such of these alkaloids as must still be included among the substances of unknown constitution is a temporary one, based upon the botanic character of the plants from which they are derived. 

In addition, it should be noted that results from these analyses of mushroom extracts indicated the presence of a previously unknown alkaloid, which I have named aeruginascin. The molecular stmcture of this substance must be similar to those of psilocybin and baeocystin. It is a compound that is soluble only in polar solvents, such as water, methanol and acetic acid. The levels of concentration of aemginascin found in the fmiting bodies is comparable to those of the other two alkaloids. The compound is characteristic of the Inocybe species, so that the analytical results of mushrooms extracts using thin-layer chromatography constitute a kind of fingerprint identification of Inocybe aeruginascem. 

The constitution of magnoline (XVI) was elucidated by degradation in 1940 but the stereochemistry of it remained unknown for many years thereafter and only recently was established. Magnoline was assigned the SR-configuration (9), as shown in formula XVI, for it was found to be the antipode of the new alkaloid berbamunine whose absolute con figuration was established as RS 9, 14). 

Until now no process was known which allows the physiologically practically inactive lysergic acid to be linked with a basic residue, such as an amino-alcohol or an amino acid, in order to prepare compounds of the type of ergot alkaloids. This was primarily due to the fact that lysergic acid was very difficult to prepare, as it was only obtainable as a degradation product from ergot alkaloids and because its constitution was unknown. 

Lappaconitine (crystalline) and septentrionaline (amorphous) are the two alkaloids isolated (83) from A. septentrionale Koelle that have been examined in some detail (84, 85, 86). Both alkaloids are monoesters of the parent amino alcohols with derivatives of anthranilic acid, but whilst the acid esterifying the parent lappaconine has been firmly identified as iV-acetylanthranilic acid (85), that (m.p. 126°) forming part of septentrionaline has been erroneously formulated (85) as CgHgOsN (see also below) its constitution is therefore unknown. 

The quinolin/4(l//)-one alkaloids with a linear aliphatic side chain at C-2 appear to be absent in fungi. Fungus Penicillium (Ascomycota phylum, Ascomycetes class, and Eurotiales order) has yielded a novel class of quinolin/ones [41], They are based on the combination of amino acids L-valine and L-isoleucine, anthranilic acid, and acetic acid [41] (Schemes 24.22, 24.23), or these amino acids and tryptamine [41] (Scheme 24.24). They constitute two small groups which can be considered as 2-substituted quinolin-4(l/f)-ones quinolactacins Al, A2, B, and C, quinolactacide and 2-substitued quinolines quinocitrinines A and B. Both are alkaloid types at present unknown from any other source. Thus, clearly fungi from Ascomycetes class deserve more attention in order to find new quinolactacins, since they showed interesting biological effect on tumor necrosis factor (TNF) [41]. 

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