The Quinolizidine Alkaloids

Most of the lupine genetic experiments were performed using seeds for analysis. Seeds genetically represent the next generation, so with Fi plants the seeds are F2, but as described in Hagberg s experiments in 1950 the 

Hybrid Sparteine Lupanine Hydroxy- lupanine Angusti- foline 

Hnminf nt fhr. rVu 1 following Segregation occurs nine like the 

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Quinolizine alkaloids, including sophocarpine, matrine and sophoridine have been determined by GC-MS techniques in kuhuang, a traditional Chinese medicine (GC = gas chromatography) <2005MI967>. Similarly, GC-MS has allowed a phytochemical study of the quinolizidine alkaloids of Genista tenera <2005MI264>. 

Quinolizidine alkaloids are non-toxic to the legumes which produce them. On the other hand, the quinolizidine alkaloids can be toxic and in some cases very toxic to other organisms. The biotoxicity of alkaloids has for some time been considered to be connected with their bitter taste" ° ". The quinolizidine alkaloids are certainly bitter in taste to humans. However, not all alkaloids are. Literature states that some pyrrolizidine and indolizidine alkaloids are not bitter in their pure forms" Furthermore, there are many non-alkaloid compounds, such as flavonoids, that are bitter in taste but non-toxic. Therefore, although quinolizidine alkaloids are bitter, the connection between biotoxicity and bitter taste is not absolute. 

The biological effect of the quinolizidine alkaloids is on the nervous system. Tremors, convulsions and pulmonary arrest have been noted in laboratory animals. Quinolizidine alkaloids cause depression, laboured breathing, trembling, convulsions and respiratory paralysis in sheep . 

Hartmann, T. 1988. Secondary metabolism of lupins Biosynthesis, translocation and accumulation of the quinolizidine alkaloids. In Proceedings of the 5th International Lupin Conference. (Twardowski, T., ed.) pp. 64-78. Poznari, Polish Academy of Sciences, Institute of Bioorganic Chemistry. 

Pummerer reaction conditions was followed by cycUzation to isomilnchnone 292 and hence to cycloadduct 293, which loses water to form a-pyridone 294. Subsequent manipulation involving deoxygenation and debenzylation completed the synthesis. In similar fashion, the azaanthraquinone alkaloid dielsiquinone was synthesized for the first time. Also, the quinolizidine alkaloids ( )-lupinine and ( )-anagyrine, and the ergot alkaloid ( )-costaclavine were synthesized using this Pummerer cyclization-cycloaddition cascade of imidosulfoxides and isomiinch-nones. 

The quinolizidine alkaloid halichlorine (203), isolated from the marine sponge Halichondria okadai, inhibits the induction of vascular cell adhesion molecule-1 (VCAM-1) at IC50 7 pg/ml, which may be useful for treating atherosclerosis, coronary artery diseases, angina and noncardiovascular inflammatory diseases [161]. 

Panek et al. [57] used this methodology as a key step in their synthesis of the quinolizidine alkaloid (—)-217(A) which was obtained in 11 steps and 19% overall yields starting from amine 256 (Scheme 13.94). 

Mende, P. and Wink, M. 1987. Uptake of the quinolizidine alkaloid lupanine by protoplasts and isolated vacuoles of suspension-cultured Lupinus polyphyllus cells. Diffusion or carrier-mediated transport J. Plant Physiol. 129, 229-242... 

The quinolizidine alkaloid matrine (32), like lupanine (27), is biosynthesized from three molecules of lysine by way of cadaverine.1,2 AM6-14C]Piperideine [as (31)] was incorporated into matrine (32) 10% of the radioactivity was found to be... 

Bitterness varies with the chemical structure of an alkaloid. With the quinolizidine alkaloids (QAs) the following scale was assessed for man Mean detection levels are 0.00085% for sparteine, 0.0021% for lupanine, and 0.017% for hydroxylupanine (503). Whereas we know a few parameters of olfactory qualities in Homo sapiens, often much less or hardly anything is known for most other vertebrates. 

For one group of alkaloids, the quinolizidine alkaloids, these experiments have already been performed (2,184,484,503,527). As mentioned before, QAs constitute the main secondary products of many members of the Leguminosae, especially in the genera Lapinas, Genista, Cytisus, Bapti-sia, Thermopsis, Sophora, Ormosia, and others (503). 

Figure 7.10 Structures of the quinolizidine alkaloids, lupinine (21), lupanine (22), cytisine (23) and multiflorine (24) and of a dipiperidine alkaloid of the ammodendrine type (25).

Bohlmann and co-workers (67CB2742) have added imine I to ethyl 2,4-pentadienoate (2) to afford adduct 3 in fair yield. Adduct 3 was further transformed into the quinolizidine alkaloid lupinine (5), as shown in Scheme I. 

The quinolizidine alkaloids (lupine alkaloids) occur in the Leguminosae family, subfamily Faboideae, where they are restricted to the Sophoreae, Podalyrieae, and Genisteae tribes (1). They have been previously reviewed by Leonard (2) in these volumes. The present review is complete to the end of 1965. 

Of particular value in structural determination of the quinolizidine alkaloids is a pair of trans bands in the IR-spectrum at 2700-2800... 

The structure of nupharamine is obviously very close to that of the quinolizidine alkaloids which also occur in Nuphar species (see Chap.38) and, for example, it is possible to degrade the quinazoline, alkaloid nupharidine (71) to (-)-nupharamine via the enamine (72) (R.T. LaLonde et al.,... 

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