Lupinine from Lupinus luteus

Alkaloids 36-41 were isolated from Lupinus luteus L. seedlings. They are considered to be lupinine esters with 4-hydroxycinnamic acids (94-100). The structures of these new alkaloids were elucidated on the basis of H NMR, MS, and chemical and enzymatic transformations. All these alkaloids were obtained from lupinine and hydroxycinnamic acid by two enzymatic systems (96-97) ligase catalyzed formation of the CoA-thioester, and transferase catalyzed lupinine ester formation from the CoA-thioester. 

Lupinine Group.—A new lupinine ester (1) obtained from seedhngs of Lupinus luteus contained traces of the c -isomer, which could be obtained from the trans-derivative by irradiation. The structure of the alkaloid was established by hydrolysis and by synthesis from (-)-lupanine and trans-4-acetoxycinnamyl chloride. ... 

While for developing of simple piperidine alkaloids, e.g., pelletierine (Punica granatum), piperine (Piper nigrum et longum), and lobeline (Lobelia inflata), only one molecule of lysine is necessary, for quinolizidine alkaloids - e.g., lupinine (Lupinus luteus), sparteine of antiarrhythmic activity (Sarothamnus scoparius), and cytisine of respiratory stimulant effect (Laburnum species) - two molecules of lysines are indispensable. It was also proved that lycopodine (Lycopodium tristachyum, clubmoss) of quinolizidine structure has no polyketide origin, but it is a modified dimer of pelletierine, which, in turn, is derivable from lysine and acetate. 

Some plants accumulate alkaloids with very different chemical structures which are nevertheless related biosynthetically. In some cases the biosynthetic route may be branched, but in some it is rather clear that the more complicated structures arise from the simpler molecules. The latter condition is encountered in lupines. While the majority of alkaloids are of a coupled quinolizidine structure, two uncommon alkaloids, lupinine and epilupinine, are of a simple quinolizidine structure. The idea that lupinine is a precursor of sparteine, i.e., a bisquinolizidine, was first proven by experiments in which radioactive lupinine was fed to the plants and radioactive sparteine and its derivatives were isolated (Schuette, 1960 Nowacki et al.y 1961). In this study, varieties of Lupinus luteus from Palestine, Portugal, and central Europe were tested. There were plants that produced only one major alkaloid, either sparteine or lupinine however, the hybrid plants which produced sparteine also produced a small amount of lupinine. Consequently, it was a typical example of intermediate inheritance. The F2... 

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