1.nicotine

2.neostigmine

3.mecaptopurine

4.trielennamine

Nicotineis apotentparasympathomimeticalkaloidfound in theNightshadefamily of plants (Solanaceae) and astimulantdrug. Nicotine is anicotinic acetylcholine receptor (nAChR) agonist,except atnAChRα9andnAChRα10where it acts as an antagonist.Itis madein the roots of and accumulates in the leaves of thenightshadefamily of plants. It constitutes approximately 0.6–3.0% of the dry weight oftobacco and is present in the range of 2–7µg/kg of various edible plants.It functions as anantiherbivore chemical; consequently, nicotine was widely used as aninsecticidein the past and nicotine analogs such asimidaclopridare currently widely used.
In lesser doses (an averagecigaretteyields about 2mg of absorbed nicotine), the substance acts as astimulantinmammals, while high amounts (50–100mg) can be harmful.This stimulant effect is a major contributing factor to the addictive properties oftobacco smoking.

Neostigmine(Prostigmin,Vagostigmin) is aparasympathomimeticthat acts as a reversibleacetylcholinesterase inhibitor.

Mercaptopurine(also called 6-mercaptopurine, 6-MP or its brand namePurinethol) is animmunosuppressive drug. It is athiopurine.

Tripelennamine(sold asPyribenzaminebyNovartis) is a drug that is used as anantipruriticandfirst-generationantihistamine. It can be used in the treatment ofasthma,hay fever,rhinitusandurticaria, but is now less common as it has been replaced by newer antihistamines. It is a member of thepyridineandethylenediamineclasses.