Lupinin

Schdpf and Thoma found that lupininic acid yielded a methyl ester (b.p. 120-2°/10 mm.) which had [aj — 19-4° to 5-8° in different batches. The f-ester furnished a gummy picrate, [a]J, ° — 41-8°, and on hydrolysis by hydrochloric acid gave a crystalline lupininic acid hydrochloride, m.p. 275°, — 13T°, identical with that described by Willstatter and Fourneau, whilst the d-ester, or ester of f-rotation below — 19-4°, furnished a crystalline picrate, m.p. 185°, [a]j, -f- 61-8°, from which pure d-epi-ester,-b.p. 126°/11 mm., [aJi, 54-8°, was prepared, this in turn yielding amorphous d-lupininie acid hydrochloride. The f-ester is convertible into ... 

Lupinine is isomeric with a hypothetical ethylquinuclidine carbinol but attempts to correlate the two structures were unsuccessful. ... 

Of the various methods of inserting a nitrogen atom in the saturated alcohol, C10H22O (II), to form lupinine, the most probable are represented by formul (X) and (XI), of which the latter was preferred. 

Although lupinine is thus a comparatively simple alkaloid its detailed chemistry has been difficult to unravel owing (a) to the presence in its molecule of two asymmetric carbon atoms as asterisked in (XI), and (6) the possibility of cis-trans isomerism in certain of its proximate (ieriva-tives. Winterfeld and Holschneider have pointed out that a further complexity arises from the presence in natural Z-lupinine of a structural isomeride, aZZolupinine for which formula (XII) is suggested. They also quote Kreig s observation that by the action of sodium on a benzene solution of Z-lupinine (m.p. 68-9° [ajo — 23-52°), the latter is converted... 

The nature of the base, CmHijN, varies. When produced from pure Mupinine, m.p. 68-9°, it furnishes on oxidation only 3-methylpyridine-2-carboxylic acid (XV) and pyridine-2 3-dicarboxylic acid. If, however, lupinine, m.p. 63-3°, is used, the resulting pyridine base on oxidation furnishes in addition 2-n-butylpyridine-6-carboxylic acid (XVI) and 6-methylpyridine-2-carboxylic acid (XVII). The conclusion is drawn that lupinine, m.p. 63-3°, is a mixture of 1-lupinine (XI) with aZlolupinine (XII), each of these components furnishing its own lupinane (XIII and XIV), and that these two lupinanes contribute to the final degradation product, the tertiary pyridine base, CioHuN, the two isomerides 2-w-Ijutyl-3-inethylpyridine (XVIII) and 2-w-butyl-6-raethylpyridine (XIX) respectively. These interrelationships are shown by the following scheme —... 

Confirmation of Karrer s formula has been provided by the investigation of special reactions of lupinine and lupininic acid and by syntheses of norlupinane and j3-lupinane. 

The lupinane group has not attracted chemists as a primary material for modification in the hope of developing substances of possible therapeutic interest. Liberalli found lupanine was inactive in avian malaria and Clemo and Swan state that this is also the case for ll-(e-diethylamino- -pentyl)aminolupinane. Lupinine -aminobenzoate has been investigated in Russia and shown to possess marked local anaesthetic action. ... 

J -Dehydroquinolizidine reacts with the enantiomeric (—)- and (-l-)-menthyl chloroformates forming (—)- and (-l-)-menthoxycarbonyl- -dehydroquinolizidines. These can be reduced as such or in the form of their immonium salts with sodium borohydride to (—)- and (+)-l-menthoxy-carbonylquinolizidines, which give (+)- and (-)-lupinin, respectively, on reduction with lithium aluminum hydride (243). The optical yield of the asymmetric reduction is about 10%. 

Sodium borohydride reduction of 4-substituted isoquinolinium salts led to vinylogous cyanamides, ureas, and urethanes, as well as the corresponding tetrahydroquinolines (640). Hydrogenation of /8-acylpyridinium salts (641) to vinylogous ureas was exploited in syntheses of alkaloids (642), leading, for instance, to lupinine, epilupinine, and corynantheidine (643, 644). Similarly, syntheses of dasycarpidone and epidasycarpidone were achieved (645) through isomerization of an a,/0-unsaturated 2-acylindole and cyclization of the resultant enamine. 

The acylation of enamines has been applied to the use of long-chain acid chlorides (388) and particularly to the elongation of fatty acids (389-391) and substituted aliphatic acids (392). The method has been used in the synthesis of the antineoplastic cycloheximide and related compounds (393-395) and in the acylation of steroids (396). Using an optically active chlorocarbonate, an asymmetric synthesis of lupinine could be achieved (397). 

Quinolizidine synthesis via intramolecular immonium ion based Diels-Alder reactions total synthesis of ( )-lupinine, ( )-epilupinine, ( )-criptopleurine and ( )-julandine [97]... 

Alkaloids, e.g. lupanine, angustifoline, sparteine, lupinine, hydroxylupanine 130°C, 17-35 h Induced blue fluorescence (Xf, = 400 nm), detection limits 10 ng. [6]... 

Alkaloids, e.g. lupanine, angustifoline, sparteine, lupinine, hydroxylupanine... 

The primary hydroxymethyl group of lupinine 6 was studied with regard to the addition of acetylene in basic systems to give the vinylated product 111 (Equation 7). As compared with aliphatic amino alcohols, the vinylation of lupinine required more drastic conditions <2004RCB242>. 

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