Arecoline analogs

Other cholinergic agonists have no therapeutic use. Muscarine (4.3) is an alkaloid of the mushroom Anumita muscaria muscarone (4.9) is its semisynthetic analog. Pilocarpine (2.2) is found in the leaves of a shrub and can be used to increase salivation or sweating. Arecoline (4.10) is also an alkaloid, and occurs in the betel nut that is used as a mild euphoriant in India and Southeast Asia. Finally, oxotremorine (4.11) is a synthetic experimental agent that produces tremors and is helpful in the study of antiparkinsonian drugs. 

In contrast to pilocarpine, arecoline acts at nicotinic receptors as well as at muscarinic sites it has been described (172) as a partial agonist at and Mg receptors. Arecoline is equipotent to its quaternary analog, iV-meth-ylarecoline, as a muscarinic agonist (172). The secondary amine, norarecoline, is a somewhat weaker muscarinic agonist than arecoline (173,174). The muscarinic activity of esters of arecaidine (the free carboxylic acid derivative... 

The five-membered ring congener (135) of arecoline is approximately 50% as muscarini-cally potent as arecoline in a guinea pig ileum assay, and the five-membered ring analog... 

Analogously, the triazole derivatives 5 and 6 have been shown to act as a nonclassical bioisosteres of the ester group as in arecoline 4, a muscarinic agonist [20, 21]. 

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