D. Narceine:
Biological Source It is obtained from the dried latex (opium) by incision from the unripe capsule of Papaver somniferum Linn., (Papaveraceae) to the extent of 0.1-0.5%.
Chemical Structure
6-[[6-[2-(Dimethylamino) ethyl]-4-methoxy-1, 3-benzodioxol-5 yl] acetyl]-2, 3-dimethoxy benzoic acid; (C23H24NO8).
Isolation The isolation of nareceine from morphine mother liquors is tedious.** It may also be prepared from narcotine or gnoscopine.***
Characteristic Features
1. The anhydrous material is very hygroscopic in nature having mp 138°C; and it: uvmax (ethanol) is 270 nm (log € 3.98).
2. Usually the alkaloid is obtained as the trihydrate.
3. The clusters of silky and prismatic needles are obtained from water having mp 176°C.
4. Its dissociation constants are pKb at 20° = 10.7; Kb = 2 × 10–11; pka = 9.3; Ka = 5 × 10–10.
5. Th pH of its saturated solution is 5.8.
6. Solubility Profile: 1g dissolves in 770 ml water; 220 ml boiling water; moderately soluble in hot alcohol; almost insoluble in benzene, chloroform, ether, petroleum ether.
7. It forms salts with solutions of alkali hydroxide and also with dilute mineral acids.
Identification Test Ethylnarceine Hydrochloride (C25H32ClNO8) (Synonym: Narcyl): It is obtained as plates from water having mp 208-210°C. It is slightly soluble in cold water, insoluble in ether; and freely soluble in hot water, ethanol and chloroform.
Uses
1. Narcyl is used as a narcotic analgesic.
2. Narcyl is also employed as an antitussive agent.
Biosynthesis of Hordenine and Mescaline Decarboxylation of L-tyrosine via pyridoxal phosphate (PLP) yields the simple phenylethylamine derivative tyramine, which an di-N-methylation gives rise to hordenine. Besides, phenylethylamine derivatives commonly exhibit either 3, 4-di- or 3, 4, 5-trihydroxylation reactions, and are subsequently derived via dopamine i.e., the decarboxylation product obtained from L-DOPA (L-dihydroxyphenylalaline). The two variants of catecholamines, namely: first, a mammalian neurotransmitter noradrenaline (norepinephrine), and secondly, the most common ‘fight or flight’ hormone released in animals from the adrenal gland due to fear phychosis or stress adrenaline (epinephrine). Furthermore, these two compounds are formed due to β-hydroxylaton and N-methylation of dopamine.
Lastly, aromatic hydroxylation and O-methylation convert dopamine into mescaline. All these reactions have been shown sequentially as given below.
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* Banholzer et al. Helv. Chim. Acta, 35, 1577 (1952).
** Merek, Chem. Ztg., 13, 525 (1889)
*** Roser, Ann. 247, 167 (1888).
