Lupanine, 13-hydroxy

The structure of Beckels ethoxylupanine (LXXV), which prepared by the reaction of bromine on lupanine in ethanol, has been elucidated (68). 17-Hydroxy lupanine is readily obtainable from it. 

The hydroboration of Ji2,i3.(jePy(Ji-olupanine (CXVII) (88), obtained from hydroxy lupanine, and subsequent oxidation lead to a mixture from which — )-retamine could be isolated. This is the enantiomer of the naturally occuring retamine. 

Hybrid Sparteine Lupanine Hydroxy- lupanine Angusti- foline... 

Cinegalline [3, 5 -di-hydroxy-3, 4 -dimethox-ybenzoyl)-13-oxy-lupanine (137) (+)-Cinegalleine [(5 -hy-droxy-3, 4 -dimethox-ybenzoyl)-13-oxy-lupanine] (138) Formylcinegalleine (for-myl-5 -oxy-3, 4 -di-methoxybenzoyl)-13-oxylupanine (139)... 

Several new lupanine derivatives with hydroxy, methoxy, oxo, and ester... 

New reports on hydroxy and methoxy derivatives include the isolation of (-)-6a-hydroxylupanine from Lygos raetam var. sarcocarpa [219] and the isolation of two methoxylated derivatives, 4a-hydroxy-13p-methoxy-lupanine and 3P,4a-dihydroxy-13p-methoxylupanine, from Acosmium panamense, as well as the full spectroscopic characterisation of the previously known ISP-methoxylupanine, Fig. (34) [220]. 

Fig. (34). Structures of the tetracyclic lupine alkaloids (-)-6a-hydroxylupanine [219], 4a-hydroxy-13 P-methoxy lupanine, 3P,4a-dihydroxy-13 P-methoxy lupanine and...

Comparison of the NMR data of 4a-hydroxy-13 P-methoxy lupanine and 3P,4a-dihydroxy-13P-methoxylupanine with that of 13P-hydroxylupanine led the authors to propose the depicted structures the hydroxyl group of 4a-hydroxy-13 P-methoxy lupanine was evident in the mass fragment at m/z 294 (C16H26N2O3) and resonances at 5 3.92 ppm and 5 63.2 ppm, the latter replacing the C-4 resonance (6 19.4 ppm) in the C NMR spectrum of 13 P-methoxy lupanine, and its a orientation was determined on the basis of the H-4 multiplicity and magnitude of the observed upfield shift of the C-4 and downfield shift of the C-3 and the C-5 resonances, when compared to a known 4P-hydroxylupanine derivative (4P-hydroxy-13a-0-(2 -pyrroyl-carbonyl)-lupanine). 

New accounts of oxo- derivatives of lupanine include the (+)-15P-hydroxy-17-oxolupanine, isolated fi-om seeds of Lupinus albus [221], and the two structures proposed for 10-oxo- and 17-oxolupanine, isolated from an East Afiican legume, Dicraeopetalum stipulare Harms, Fig. (35) [222]. 

New reports of lupanine esters concern the isolation and characterisation of the new structures (-)-3P-hydroxy-13a-tigloyl-oxylupanine from the seedlings of Cytisus scoparius [223] and cineroctine from twigs of Genista cinerea subsp. Cinerea [224], Fig. (36). The full C NMR characterisation of the previously known cineverine was also reported[224]. 

Fig. (36). Structures of the lupanine esters (-)-3 i-hydroxy-13a-tigloyloxylupanine [223], cineroctine [224] and cineverine [224].

The solvolysis of either tosylate with methanol gives 13-epimethoxy-lupanine, identical with the natural alkaloid (CXXVI). The reactions of the 13-tosylates are influenced by the specific stereochemistry of rings C and D. The corresponding tosylate of hydroxy-a-isolupinane does not react in the same way. 

Full confirmation of the proposed structure came from the enzymatic synthesis of (-)-3(3-hydroxy-13a-tigloyloxylupanine from (-)-3(3,13a-dihydroxylupanine, tigloyl-CoA and DHLTase [(-)-3 P, 13 a-dihydroxy lupanine 13-0-tigloyloxyltransferase]. 

C.sHjjNjO, Mr 246.35, mp. 108-109 °C, [a]g -317° (CHgOH). A quinolizidine alkaloid of the sparteine type from some Lupinus species and Cadia ellisiana (Fabaceae). Analogous to lupanine a I3a-hydroxy derivative (C15H22N2O2, Mr 262.35) of M. is also known. It is found in Lupinus albus and L. cosentinii. A depressive activity of M. on the central nervous system has been described. ... 

The main QAs in L. luteus are lupinine and its esters (E/Z isomers of (4 -hydroxy-3 -methoxycinnamoyl) lupinine) and ((4 -hydroxycinnamoyl)lupinine) and sparteine minor amounts of p-isosparteine, tetrahydrorhombifoline, 17-oxosparteine, lupanine, feruloyllupinine are present [8, 11]. 

Figure 2.11b. Segregation pattern in F2 progeny. Crosshatched fields represent plants like the dominant parent. Vertical lines represent plants that produce only lupanine. Horizontal lines and a clear field represent those plants that produce sparteine only. The plants represented here by the horizontal broken lines are able to transform introduced lupanine into hydroxy sparteine.

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