Nornicotine structure

V-Ethylnomicotine (3) was isolated from Nicotiana tabacum, and its structure determined by UV, IR, HRMS, Iff and 13c NMR, and by synthesis from nornicotine [61]. It was subsequently isolated from N. rustica, after the root cultures had been fed Af-ethylputrescine dihydrochloride [62]. 

The most important natural sources of minor tobacco alkaloids are from Nicotiana species, and at least eight minor tobacco alkaloids are shown in Figure 1. Since the chemical structures and physical properties of these minor tobacco alkaloids are similar to that of nicotine, some of them are shown to exhibit similar pharmacological activities as those of nicotine, although with a much lower potency. Table 2 shows their relative molar potency in some pharmacological systems. When nornicotine or anabasine was applied to the cat cervical ganglion, initial stimulation was followed by paralysis. On the autonomic ganglion and neuromuscular junction, nornicotine is only one-fifth to one-tenth as active as nicotine. Both nornicotine and anabasine have vaso-depressor action and affect the respiratory system. 

As in the case of nicotine and nicotyrine, several structural isomers of nornicotine have been synthesized. 2, 2-Nomicotine is obtained as an intermediate in the synthesis of 2, 2-nicotine (383). 

Interest in alkaloids of the nicotine group appears to be on the increase. A review has appeared covering tobacco-specific nitrosamines, which may be causative factors in tobacco-related cancers. The solution conformation, and proton, deuterium, carbon-13, and nitrogen-15 n.m.r. spectra of nicotine and its 2- and 4-isomers, have been studied. A new synthesis of nornicotine and nicotine has been described, and a quantitative carbon-13 n.m.r. spectral analysis of nicotine that is labelled at positions 1, 2, and 3 with carbon-13 been presented. The synthesis and mass spectrometry of several structurally related nicotinoids have been reported. Nicotine is dehydrogenated on irradiation in benzene solution in the presence of benzophenone to l -methyl-2 -(3-pyri-dyl)pyrrole. ° Nornicotine has been synthesized in four steps from 3-bromo-pyridine and N-3-butenyl-phthalimide, using a palladium-catalysed vinylic... 

Richardson CH, Shepard HH (1930) The insecticidal action of some derivatives of pyridine and pyrrolidine and some aliphatic amines. J Agric Res 40 1007-1015 Richardson CH, Craig LC, Hansberry TR (1936) Toxic action of nicotine, nornicotine and anabasine vpor Aphis rumicis. J Econ Entomol 26 850-855 Riechers DE, Timko MP (1999) Structure and expression of the gene family encoding putrescine V-methyltransferase in Nicotiana tabacum new clues to the evolutionary origin of cultivated tobacco. Plant Mol Biol 41 387 01... 

The thermal reactions that accompany the smoking of tobacco and cannabis furnished important structural information on tobacco alkaloids. The pyrolysis of tobacco alkaloids yielded products such as quinoline and isoquinoline and nicotinonitrile which are probably derived from nornicotine and mysomine. Pyrolysis of natural polyenes such as -carotene yielded ionene and small amounts of toluene, /n-xylene, and 2,6-dimethylnaphthalene. 

Nicotine. The use of the alkaloid nicotine [16] as an insecticide has been known for at least two centuries. Its use in field applications was superseded by the pyrethroids which are of significantly lower toxicity to mammals than nicotine (LDso 3-188 mg/kg orally) (Coats, 1994). Nicotine and the major related alkaloids nornicotine and anabasine (structures not shown) are believed to act by blocking acetylcholine receptors (Corbett et al., 1984). 

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