R. Greinwald

The alkaloid pattern of Cytisophyllum sessilifolium (Fabaceae-Genisteae)

A survey of alkaloids from Cytisophyllum sessilifolium has shown the presence of several quinolizidine and dipiperidine alkaloids. The investigation afforded a new alkaloid, 7-hydroxylupanine. The structure of this alkaloid was assigned spectroscopically, α-Isosparteine, sparteine, β-isosparteine, ammodendrine, lusitanine, isolupanine, 5,6-dehydrolupanine, lupanine, a tentative dihydroxylupanine, cis-adenocarpine and trans-adenocarpine have been found. The co-occurrence of quinolizidine alkaloids and adenocarpine appears to be a good chemotaxonomic character of the genus Cytisophyllum.

Alkaloids of Virgilia divaricata and V. oroboides

Abstract orty-three quinolizidine alkaloids, and the dipiperidyl alkaloid, ammodendrine, have been found in Virgilia divaricata and V. oroboides . Three new quinolizidine alkaloids were detected, viz. virgilidone, 4β- O -(2′-pyrrolylcarboxyl)- epilupinine and 4β-hydroxy-1 1- O -(2′-pyrrolylcarboxyl)-epilupinine. The distribution of alkaloids in air-dried leaves, flowers, pods, seeds and twigs of the two species was also investigated. The unique combination of bi-, tri- and tetracyclic quinolizidine alkaloids is typical of the genus Virgilia .

Cytisine-12-carboxy-ethylester, a quinolizidine alkaloid from Laburnum watereri and its occurrence in the leguminosae

Abstract A new lupin alkaloid, cytisine-12-carboxy-ethylester, was isolated from suspension cultures of Laburnum watereri. Its structure was determined by spectroscopic data and by direct comparison with a synthetic sample. The distribution of the new alkaloid amongst different genera of the Leguminosae is reported.

Alkaloids of the genera Dicraeopetalum, Platycelyphium and Sakoanala

Abstract The presence of alkaloids in Dicraeopetalum, Platycelyphium and Sakoanala (Fabaceae, tribe Sophoreae) is reported for the first time. All three of these genera have a typical α-pyridone pattern, with N -methylcytisine, cytisine, N -formylcystisine, N -acetylcytisine, 5,6-dehydrolupanine, lupanine, anagyrine, baptifoline and epibaptifoline as major alkaloids. Other compounds that were identified include the bicyclic quinolizidines lupinine and epilupinine and the bipiperidyl alkaloid ammodendrine. The discovery of α-pyridone alkaloids in Dicraeopetalum in particular, has important taxonomic implications and casts further doubt on the monophyly of the Cadia group. Dicraeopetalum (and Lovanafia ) may be better placed in the Sophora group, close to Neoharmsia, Sakoanala and Bolusanthus , thereby amalgamating all the Old World sophoroid genera with recaulescent bracts and α-pyridone alkaloids.

Taxonomic significance of major alkaloids in the genus Priestleya

Abstract The genus Priestleya is known to contain the bipiperidyl alkaloid anabasine and an alkaloid tentatively identified as lupanine. In a study of 16 different species, several quinolizidine alkaloids and some bipiperidyl alkaloids were identified. A remarkable difference was found between the two sections of Priestleya : sect. Priestleya contains sparteine, lupanine and other tetracyclic quinolizidine alkaloids, while the sect. Anisothea contains the bipiperidyl alkaloid anabasine and the bicyclic quinolizidine lupinine. The chemical distinction agrees with morphological evidence that the generic concept of Priestleya is artificial and that two distinct genera should be recognized.

The taxonomic significance of alkaloids in the South American genus Anarthrophyllum

Abstract The major alkaloids of the genus Anarthrophyllum have been identified for the first time. More than 28 alkaloids were detected in nine extracts from six different species. All the extracts showed a typical α-pyridone pattern, with sparteine, β-isosparteine, N -methylcytisine, cytisine, 5,6-dehydrolupamine, lupanine, N -formylcytisine, N -acetylcystisine and anagyrine as major alkaloids. Lupinine, epilupinine, ammodendrine and lamprolobine were also present as major compounds in some of the extracts. Tetrahydrocytisine and structurally related alkaloids occur in most of the species, but rarely in more than trace amounts. The discovery of α-pyridone alkaloids in Anarthrophyllum has important taxonomic implications. It provides evidence that the true affinities of the genus are with the Argyrolobium group (presently in the tribe Crotalarieae) and Lupinus (tribe Genisteae) with which it shares, in addition to the alkaloid pattern, circumcauline stipules, a trifid lower lip of the calyx and a similar chromosome number. The alkaloid data agree with morphological evidence that Anathrophyllum and Sellocharis will be better placed near Lupinus in the tribe Genisteae.

ALKALOID VARIATION IN THE LUPINUS PUSILLUS GROUP (FABACEAE: TRIBE GENISTEAE)

Abstract The major alkaloids of Lupinus pusillus and related species were studied by GC and GC-MS. More than 25 alkaloids were detected in 20 extracts from L. flavoculatus, L. kingii, L. odoratus, L. pusillus and L. shockleyi . Esters of alkaloids appear to be absent, and sparteine, β-isosparteine, isolupanine, 5,6-dehydrolupanine, lupanine and anagyrine are the major alkaloids. The presence of the α-pyridone pathway is thus confirmed, with anagyrine as the major seed alkaloid in four of the five species. Lupinus seems to differ from other α-pyridone-bearing genera of the tribe Genisteae, which accumulate N -methylcytisine or cytisine in the seeds and not anagyrine. Despite the small number of samples and populations studied, the remarkable differences between the species showed that the alkaloids of Lupinus may provide valuable taxonomic information even at the species level.

Taxonomic significance of alkaloids in the genus Liparia (Fabaceae – Liparieae)

Comparative GC and GC–MS analyses of the alkaloids of Liparia splendens (Burm. f.) Bos & De Wit and L. parva Vog. ex Walp. have shown that the two species differ considerably. L. splendens contains ammodendrine (a bipiperidyl compound) as major alkaloid, while L. parva has sparteine, lupanine and other quinolizidine alkaloids as major alkaloids. Only small quantities of bipiperidyl alkaloids were present in the latter. The two species of Liparia are morphologically similar and the different alkaloid patterns are therefore quite unexpected. Our results support the idea that different pollination mechanisms may lead to an enlarged taxonomic distance between closely related species.