alkaloids
DESCRIPTION
Everything about alkaloidsTRANSCRIPT
AlkaloidsDr. AmitrRatn Gangwal
IndoreIndia
(images and structures are taken from internet and not the authors original content or creation)
Plant secondary metabolites
Alkaloid
Dhatura fruit: To Lord Shiva
Celebrities (brat/s)
Rahul MahajanLindsay LohanBritney SpearsJaswant Singh (exception)Paris HiltonFardin Khan
Most of them were convicted in
court on account of using or
possessing cocaine and other
banned drugs.
Few famous/celebrated drugs
obtained from plants are:
• Cocaine
• Atropine
• Papevarine
• Morphine
• Quinine
• Codeine
• Thebaine
• Caffeine
• Reserpine
• Nicotine
• Vincristine and vinblastine etc
Vinca rosea/Sadabahar/Periwinkle
They all are alkaloids and possess important pharmacological actions viz anticancer, hypotensive, relaxants, painkiller etc.
Most of the allopathic drugs used today, trace their roots to plants metabolites in general and to alkaloids in particular.
Jumbo
molecules
Vincristine
Reserpine
Tubocurarine
IntroductionThey are alkali like compound.
Mainly obtained from plants.
Should possess nitrogen atom essentially in the ring (heterocyclic form)
Should be potent.Should respond to classical four
tests meant for their identification.
Distribution:SolanaceaeRubiaceaeLiliaceaeAmaryllidaceae are the few
families, plants of which are rich in alkaloids.
Example of lower plant possessing alkaloids is fungal alkaloid providing ergot which possess a gamut of biological actions.
PropertiesMainly colorless, crystalline solid.
But coniine, sparteine and nicotine are liquid and berberine and betanidine possess colors.
In general alkaloidal salts are soluble in water and their free forms are soluble in organic solvents (mainly ether and chloroform).
Some of the pseudo and proto alkaloids show higher solubility in water e. g. colchicine and caffeine.
They are basic in nature due to the lone pair of electrons on nitrogen.
Their salt formation with an inorganic acid prevents many a time their decomposition.
ExtractionOne has to consider following steps in sequential manner for the extraction of alkaloids:
Separation of the alkaloid from unwanted material(Hardly any plant which contains only one alkaloid exclusively.)
Separation of each individual alkaloid from the mixture using chromatographic techniques.
Extraction depends mainly on: The alkaline nature of most alkaloids
The ability and ease of formation of alkaloidal salt with acids
Relative solubilities of resulting salts either in organic or aqueous media.
Identification testsMayer’s reagentDragendorff’s reagentWagner’s reagentHager’s reagentBut proto and pseudo alkaloids
do not respond to these tests and so they got the names.
Functions in plantsWaste metabolites Waste products or secretary
productsThey play defensive roles in
plants.But their exact role in plants is a
debatable issue.
Nomenclature From the generic nameAtropine from Atropa belladona
From the specific name
Belladonine from A. belladonaFrom common name
Ergotamine from ergot
From their specific pharmacological actions
Narcotine from Papaver somniferum
Morphine from p somniferum.
From the name of discovererPelletierine from the bark of Puniea granatum.
Generally with all the alkaloids suffix ine is added.
Classification They can be classified based on
their:pharmacological actionsbiosynthetic precursors and mostly used chemical structure which we will see in detail:
Pyrorolidine alkaloids: hygrine
Piperizine:lobeline
Tropane: atropine
Quinoline: quinine
Isoquinoline:morphine
Aporphine: boldine
Indole: ergometrinine
Imidazole: pilocarpine
Purine: caffeine
Steroidal: solanidine
BiosynthesisThey are mainly derived from aromatic amino acids in the plants. But again few alkaloids defy this rule.
Some interesting facts about alkaloids
Hemlock alkaloid (Conium maculatum)
Opium poppy
No manipulation in opium alkaloids can be done without the permission of Govt. of India.
Neemuch and Ghazipur: Govt. opium factories.
Alkaloid colony in Neemuch.
Alkaloids pvt. ltd. (Secunderabad, AP)
Individual drugs
Opium
Thank you