Roland Greinwald

Alkaloids of the genus Poecilanthe (Leguminosae: Papilionoideae)

Abstract The presence of alkaloids in the genus Poecilanthe is reported for the first time. Epilupinine, 4β-hydroxyepilupinine, dihydrolusitanine, dihydroammodendrine, lusitanine, N -methylcytisine, cytisine, lupanine, N -formylcytisine, anagyrine, baptifoline, camoensidine and four novel alkaloids were found as major alkaloids in leaves and seeds of the genus Poecilanthe . Tashiromine, acetylepilupinine, ammodendrine, α-isolupanine, 5,6-dehydrolupanine, aphyllidine, aphylline, thermopsine, epibaptifoline, rhombifoline, tinctorine, 11-allylcytisine, acetylbaptifoline and at least seven unknown compounds were found as minor alkaloids in the extracts studied. The co-occurence of different types of quinolizidine (bicyclic lupinine-type, lupanine-type, leontidine-type and α-pyridone-type) and bipiperidyl alkaloids appears to be a good chemotaxonomic marker for the genus. The presence of alkaloids in Poecilanthe suggests a relationship of this genus with the tribes Sophoreae or Brongniartieae rather than with the Dalbergieae. The alkaloidal data indicate that the genus can be divided into two phytochemical groups: one group of species accumulating mainly α-pyridone alkaloids and a second group accumulating bicyclic quinolizidine alkaloids, with α-pyridones being totally absent.

Über die Alkaloidzusammensetzung der oberirdischen Teile von Laburnum watereri (Kirchn.) Dipp.

Summary The alkaloid composition of the overground parts (leaves, petioles, stems, flowers, fruits and seeds) of Laburnum watereri (hybrid of Laburnum alpinum × L. anagyroides ) and its seasonal changes (from march to november) have been studied by different chromatographic (TLC, capillary GC) and spectroscopic (GC/MS, HRMS, 1 H-NMR, 13 C-NMR, IR, UV) methods. Seeds only contain cytisine. Besides cytisine, traces of methylcytisine and ammodendrine 12 further alkaloids could be identified in the fruits, among which β-isosparteine, 14e-hydroxysparteine and epi-baptifoline have been found for the first time in the genus Laburnum . Following the seasonal changes of the alkaloid composition of the fruits, an increase of epibaptifoline and ammodendrine was established during ripening, while the content of the main compound cytisine strongly declined. The highest total amount of alkaloids (with 80 to 90% cytisine) was found in the buds in the spring. During the further development of the leaves, the cystine content decreases and a methylation of this alkaloid begins. In summer the alkaloid concentration reaches the lowest level. In the course of July epi-baptifoline (erroneously reported as methylcytisine in literature) increases and becomes the main alkaloid for the following 6 months.

Distribution and taxonomic significance of alkaloids in the Genista cinerea agregat

Abstract The alkaloid pattern of the Genista cinerea agregat was investigated by GC and GC-MS. At least 15 alkaloids were found in G. cinerascens , 20 alkaloids in G. majorica and 16 alkaloids in G. cinerea ssp. ausetana . Twigs of G. cinerascens contained the α-pyridone alkaloids cytisine and anagyrine as main compounds, whereas lupanine, 13-hydroxylupanine and the ester alkaloids 13-tigloyloxylupanine and 13-benzoyloxylupanine were found as predominant constituents in twigs of G. majorica and the different subspecies of G. cinerea . Investigations of seeds, pods, fruits and flowers confirmed the alkaloid pattern found in twigs. The alkaloid data give no support for a close affinity between G. cinerascens and the other two species of the agregat, G. majorica and G. cinerea .

A survey of alkaloids in the genus Lamprolobium Benth. (Fabaceae: Brongniartieae)

Abstract The alkaloids of Lamprolobium fruticosum and L. grandiflorum have been studied to provide data for comparisons with other genera of the tribe Brongniartieae. Both species contained the quinolizidine alkaloids cytisine, N -methylcytisine, anagyrine and epibaptifoline as major compounds. L. fruticosum differs from L. grandiflorum in accumulating quite high amounts of bicyclic lupinine-type alkaloids and lamprolobine thus indicating the chemotaxonomic value of alkaloids at the subgeneric level. The distribution of lamprolobine, however, varied greatly among different samples of L. fruticosum . The co-occurrence of lupinine-type and α-pyridone-type alkaloids distinguishes this genus from Hovea and Templetonia and suggests an affinity with the South American genus Harpalyce .

A survey of alkaloids in the genera Harpalyce and Brongniartia (Fabaceae—Brongniartieae)

Abstract The presence of alkaloids in six species of Brongniartia and three species of Harpalyce is reported. This survey revealed remarkable qualitative differences in the alkaloid profiles of these two genera. B. discolor, B. lupinoides, B. sousae and B. intermedia showed a typical α-pyridone pattern, with cytisine, anagyrine and baptifoline as major alkaloids. In leaves of the first three species ormosanine-type alkaloids occurred additionally. B. flava and B. vazquezii are devoid of α-pyridones, but accumulate lupanine, hydroxylated lupanines and ester alkaloids. All three species of Harpalyce were similar in accumulating α-pyridones, but H. formosa differed from H. brasiliana and H. pringlei in the presence of epilupinine. In general the alkaloid profiles of Brongniartia and Harpalyce show similarities to those of the Australian genera Hovea, Lamprolobium, Plagiocarpus and Templetonia and support therefore the actual concept of the enlarged tribe Brongniartieae.

Seed alkaloid composition of Lupinus tassilicus maire (Fabaceae: Genisteae) and comparison with its related rough seeded lupin species

Abstract Seed alkaloid composition of L. tassilicus from African Central Sahara was studied and compared with its related rough seeded Old World lupin species. Epilupinine and multiflorine clearly represented the major alkaloids (90–99% of total yield) in all the 12 samples of the five species surveyed. Alkaloid data did not reveal significant qualitative changes among samples and provided a real fingerprint for the whole group of rough seeded lupins. On the basis of the ratio of epilupinine to multiflorine, it was possible to distinguish two subgroups of populations: on one side, those accumulating predominantly multiflorine and essentially distributed in Mediterranean region; on the other side, those containing epilupinine as the major alkaloid and mainly originated from the desert and arid regions of Africa. Alkaloid data support the close affinity between the L. tassilicus forms of Algeria and Libya, and between these latters and L. digitatus from Egypt. However, further investigations are still to be developed to elucidate the taxonomic status of L. tassilicus within the rough seeded lupin species group.

A survey of alkaloids in Templetonia biloba (Benth.) Polhill (Fabaceae: Brongniartieae)

The presence of alkaloids in Templetonia biloba has been described for the first time. This species contained an unusual combination of α-pyridone alkaloids and tetra hydrocytisine derivatives with a fully saturated ring A. Cytisine, N-methylcytisine, tetra hydrorhombifoline, tetra hydrocytisine, N-methyl-tetrahydrocytisine, lupanine and 13-hydroxylupanine were found as major constituents. Other compounds that were identified include the bicyclic quinolizidine alkaloids lupinine and epilupinine. Together with the absence of ormosanine-type quinolizidines, which represent typical constituents for other species of Templetonia, these alkaloid data confirm morphological evidence that Templetonia biloba is probably misplaced in the genus Templetonia. Templetonia biloba was formerly thought to be a member of the genus Bossiaea. The alkaloid pattern of T. biloba supports its earlier removal from the genus Bossiaea, where quinolizidine alkaloids were totally missing and tyramine was found as a major compound.

The alkaloid pattern of Plagiocarpus axillaris (Fabaceae: Brongniartieae)

Abstract As part of a detailed survey of alkaloids in the tribe Brongniartieae, the alkaloid pattern of the monotypic genus Plagiocarpus has been investigated. All extracts contained the quinolizidine alkaloids sparteine and cytisine as major compounds. Moreover β-isosparteine, 11,12-dehydrosparteine, 17-oxosparteine and anagyrine represented major alkaloids in some extracts. A group of sparteine derivatives, especially remarkable amongst them three different hydroxysparteines, and the bicyclic alkaloid lupinine contributed to the alkaloid profile as minor constituents. The co-occurrence of lupinine- and α-pyridone-type alkaloids connects this genus with the other Australian members of the Brongniartieae and confirms the monophyly of this tribe. The alkaloidal data support the idea that Plagiocarpus is more closely related to Templetonia incana, T. biloba and Lamprolobium than it is to Hovea and the remaining species of Templetonia . The presence of hydroxysparteines in both taxa could point to an especially close link of Plagiocarpus and T. incana .

Ester alkaloids of Genista cinerea subspecies Cinerea

Abstract Two ester alkaloids, cineverine and a new compound, for which we suggest the name cineroctine, were isolated from twigs of Genista cinerea subsp. cinerea . Their structures were determined by spectroscopic methods to be 13α-(3′, 4′-dimethoxybenzoyl)oxylupanine (cineverine) and 13α-(3-hydroxy- cis -oct-5-enoyl)oxylupanine (cineroctine), 13- O -axial derivatives of lupanine. The distribution of these ester alkaloids amongst the different species of the section Spartioides of the genus Genista is recorded.

A CHEMICAL DICHOTOMY IN QUINOLIZIDINE ALKALOID ACCUMULATION WITHIN THE SECTION SPARTIOIDES OF THE GENUS GENISTA (FABACEAE: GENISTEAE)

Abstract A previous study had revealed unexpected differences in the alkaloid profiles within the Genista cinerea aggregate belonging to the section Spartioides . Extending these analyses the alkaloid patterns of 10 further species of the section Spartioides were investigated. At least 31 alkaloids were detected by GC and GC-MS. A chemical dichotomy was demonstrated for the species of the section Spartioides : one group of species contained the α-pyridone alkaloids cytisine, N -methylcytisine and anagyrine as major alkaloids, while the other group contained lupanine, 13-hydroxylupanine and its esters as main compounds. The alkaloidal data do not support the actual concept of the section Spartioides .