Aconitine alkaloids

Aconite alkaloids Aconitine, molecular formula C34H47NO11, is an example of an aconite alkaloid. It is soluble in organic solvents, e.g. CHCI3 and CeHg, and sfightly soluble in alcohol or ether, but insoluble in water. Aconitine is an extremely toxic substance obtained from the plants of the genus Aconitum (family Ranunculaceae), commonly known as aconite or monkshood . It is a neurotoxin, and used for creating models of cardiac arrhythmia. 

Oxonine 1, a derivative of the diterpene alkaloid aconitine, undergoes smooth oxidation when treated with exactly one equivalent of periodic acid. The product thus obtained, which shows no aldehyde or ketone absorption in the ir spectrum, is converted into 2 when heated in dilute aqueous base with air passing through the solution. 

Alkaloids of Aconitum kusnezojfii Reichb.—Researchers in the Peoples Republic of China have reported studies on the alkaloids of Aconitum kusnezojfii Reichb. that had been collected in Inner Mongolia.29 The pharmacological effects of extracts of these plants were studied in several animal systems.30 The known alkaloids aconitine (55), mesaconitine (56), hypaconitine (57), and deoxyaconitine (79) were identified on the basis of comparison of their physical and chemical properties with those of authentic samples. In addition, a new base, beiwutine (C33H45N012 m.pt 196—198 °C), was reported. This base formed a perchlorate salt (m.pt 255—257 °C) and a tetra-acetate derivative (m.pt 242—244 °C). From the H and 13C n.m.r., i.r., and mass-spectral data, structure (80) was proposed for beiwutine. 

Miscellaneous alkaloids Aconitine Amanitin Anabaseine Arecoline Batrachotoxin Capsaicine... 

Cells carefully control the homeostasis of their ion concentrations by the action of ion channels (Na, K , Ca " channels) and throu Na, K -ATPase and Ca -ATPase. These channels and pumps are involved in signal transduction, active transport processes, and neuronal and neuromuscular signaling. Inhibition of transport processes (ion channels, carriers) is achieved by (Table IV) acronycine, ervatamine, harmaline, quinine, reserpine, colchicine, nitidine, salsolinol, sanguinarine, stepholidine, caffeine, sparteine, monocrotaline, steroidal alkaloids, aconitine, capsaicine, cassaine, maitoxin, ochratoxin, palytoxin, pumiliotoxin, saxitoxin, sole-nopsine, and tetrodotoxin. 

MONK S HOOD (Wolfsbane), Aconitum napdlus, L., Family Ranunculaceae, grows wild in Europe and is cultivated as an ornamental plant. The whole plant, mainly the root and seed, is poisonous through the occurrence of the alkaloid aconitine (0.5-1.5% in the root). The aconitine content of the drug varies considerably because the alkaloid is easily hydrolysed to the weakly active compounds benzoylaconine and aconine. 

Some alkaloids are mind altering or hallucinogenic, such as those of the family Papaveraceae or the poppy family, whereas others may adversely affect vital organs such as the liver and kidneys. The most deadly produce cardiac arrest and respiratory failure, that is, near-immediate suffocation. The effect of the alkaloids in curare, used by South American Indians to kill prey, should be recalled. Also high on the toxicity list is the alkaloid aconitine, derived from the roots of wolfsbane or monkshood, for example, the species Aconitum napellus of the family Ranunculaceae. It... 

Alkaloids of Aaonitum subouneatum Nakai.- Researchers in Hokkaido, Japan, have reported the isolation of a new alkaloid from plants of A. subouneatum. Deoxyjesaconitine (90), C35H4gNO i, m.p. 174-176°C, was isolated by high-performance liquid chromatography of the less polar fraction, from which deoxyaconitine (11) and hypaco-nitine (12) were also isolated. The major alkaloids from this species were the more polar alkaloids aconitine (14), mesaconitine (10), and jesaconitine (13). The and n.m.r. and i.r. data were used for the structural assignments. The n.m.r. chemical shifts are reported. 

Hypaconitine was isolated for the first time in 1929 (32) and frequently occurs with the closely related alkaloids aconitine (4) and mesaconitine... 

The tubers of A. karakolicum collected from the Terskei Ala-Tan ranges of the Kirghiz S.S.R. yielded a new alkaloid (16) designated as aconifine (C34H47NO12 mp 195-196°). Along with this new alkaloid, the tubers of A. karakolicum also afforded the well-known Ci9-diterpenoid alkaloid aconitine (4) and the two known -diterpenoid alkaloids, songorine and napelline. 

Aconine, the amino alcohol, is the parent of two ester-alkaloids, aconitine (the acetate benzoate) and jesaconitine (the acetate p-methoxybenzo-ate), and differs from mesaconine, the parent of mesaconitine (the acetate benzoate), only in the A-alkyl substituent. Aconine carries an 7V-ethyl (40, 49) and mesaconine an A-methyl group these two compounds thus yield the same nitro-AT-nitroso derivative, and aconitine and mesaconitine give the same oxidation product, oxonitine (41), with elimination of the A-alkyl group. It is convenient, therefore, to combine the discussion of these closely related alkaloids. 

All three alkaloids, aconitine, jesaconitine, and mesaconitine, give triacetates, and the parent amino alcohols, aconine and mesaconine, give penta-acetates of the eleven oxygen atoms in aconitine, four are therefore present in the two ester groupings and three as free hydroxyl groups. Because they can readily be esterified, all these groups may be assumed to be primary or secondary. 

Toxic effects are caused by the alkaloid aconitine (Fu et al. 2006 Lin et al. 2004). Aconitine and other alkaloids activate the sodium channel and have widespread effects on the excitable membranes of cardiac, neural, and muscle tissues. Muscarinic activation also causes hypotension and bradyar-rhythmias (Chang and But 1986). 

Four Aconitum alkaloids (aconitine, mesaconitine, hypaconitine, jesaconitine) were extracted from blood and separated on a 40°C C,g colunrn (2 = 260nm for jesaconitine and 235 nm for all others). A 14/86 THF/water (0.2% TEA) mobile phase generated baseline resolution and elution in 15 min. Calibration curves from 100 to 10000ng/mL and detection limits of 50ng/mL were reported [833]. 

Most of the aconite species contain one or more characteristic alkaloids all of which are derivatives of isomeric aconines. The B.P,C, aconite is confined to the root (the leaf also contains similar alkaloids) of A, napellus, Linn., which contains the crystalline alkaloid aconitine (acetylbenzoyl-aconine), C34H47O11N, Mol. Wt. 645 8, with smaller proportions of noncrystalline alkaloids. 

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