Cytisine methylation

Hydroxy- sparteine Sparteine Lupanine Thermo- psine Cytisine Methyl- cytisine Bapti- foline Not identified... 

In 1931 Ing pointed out that formula (II) and (III) do not contain methyl or potential methyl groups in j ositions 6 and 8 which they occupy in cytisoline. Further, a partially reduced quinoline ought to oxidise easily to a benzenecarboxylic acid and so far the only simple oxidation, products recorded from cytisine were ammonia, oxalic acid and isovaleric acid. Distillation of cytisine with zinc dust or soda-lime yields pyrrole and pyridine, but no quinoline. On these grounds Ing suggested that cytisine should be formulated without a quinoline nucleus, and that the reactions which indicate the presence of an aromatic nucleus in the alkaloid can be accounted for by an a-pyridone ring. This a-pyridone nucleus can... 

Cytisine. This base belongs to the same pharmacological group as nicotine.It is a powerful poison causing nausea, convulsions and death by failure of respiration. The nicotine-like action is shared by A -methyl-cytisine but the latter, according to Scott and Chen, who have made a detailed study of its action, is weaker and has about one-fortieth the toxicity of nicotine. 

Lupanine-Sparteine Group.—A new alkaloid isolated from Echinosophora koreensis was shown to be N-(3-oxobutyl)cytisine (14) by means of spectroscopic studies and by its synthesis from the reaction of cytisine (13) and methyl vinyl... 

Labeled cadaverine and lysine when administered to Cytisus laburnum L. gave rise, in good yield, to cytisine and its JV-methyl derivative. The formation of iV-methylcytisine from cytisine is a secondary process and may be a detoxication mode. The elimination of C-2 as benzoic acid provided one fifth of the total activity. The formation of cytisine (VIII) from sparteine by degradation is a possibility. Nowacki and Byerrum 27-30) were unable to observe activity at C-2 of cytisine and arrived at other conclusions. In view of the ready conversion of angustifoline into epihydroxylupanine (31-33) the former was postulated as the precursor of the tetracyclic lupine bases (34). 

This alkaloid (CII), C15H22O2N2 (mp 169° [o ]d + 13.3°) was obtained from Argyrolobium megarhizum Bolus along with (— ) aphyllidine, cytisine, and iV-methyl cytisine. On reduction it gives (— )-sparteine and therefore it is CII (82). 

In addition to matrine and its A-oxide, Sophoraflavescens Ait. contains methyl cytisine, anagyrine, baptifoline, and a newly described base, sophoranol (CXXXV), C15H24ON2 (mp 171° [a]i) +66°), which is a hydroxymatrine 103, 104). The configuration of matrine has been... 

CaulOphylline. l,2,3.4,S,6-Hexahydro-3-methyl-1,5-methaao-8H-pyrido[I,2-a][l,SJdiazocin-8-one l2-meth-ylcytisine V-methy]cytisine. Cl2H,jNjO mol wt 204.26. C 70.56%, H 7.89%. N 13.72%. O 7.83%. From Caulophylium thalictroides Michx., Berberidaceae Power, Salway, J. 

The anthelmintic activity of the quinolizidine alkaloids has been reviewed [394]. It is well recognised that quinolizidine alkaloids deter or repel insects and non-insect herbivores [394], These compounds can interfere with protein biosynthesis and some bind to acetylcholine receptors with high affinity. (-)-N-methylcytisine (233) and (-)-anagyrine (234) were isolated from the roots of Sophora flavescens, a plant used in traditional Chinese medicine as an anthelmintic. N-methyl cytisine was twice as active as anagyrine but only half as active as (-)cytisine and nicotine [395,396] The alkaloids (3-6 pg) inhibited reproduction of B. xylophilus in the cotton balls assay. 

Spath (178) believed that the quinoline ring system was present in cytisine, although he observed that no migration of the V-methyl group took place when model compounds, l,8-dimethyl-2-quinolone and... 

The modified Hofmann exhaustive methylation of another reduction product of cytisine was useful in confirming the tertiary and bridge-head... 

A base isolated from Euchresta japonica by extraction with methanol was shown by spectroscopic studies and by its synthesis from (-)-cystisine and methyl bromoacetate to be methyl 12-cytisine acetate (4). This compound is apparently an artifact derived from the new alkaloid (5) extraction of the plant with aqueous ethanol gave the latter compound as its zwitterion, and the methyl ester (4) was not detected. "... 

It has been found that isophoridine and allomatrine are not biosynthetic intermediates in Sophora alopecuroides. Curiously, alkaloids of the sparteine (5) type were found to be precursors of those with the matrine (6) skeleton. Methylation of cytisine (7) was observed to be reversible. ... 

---