Alkaloids

Alkaloids

Organic nitrogenous plant secondary metabolites which are pharmacologically active

Nicotine, Coniine, Sparteine, Arecoline

NOT solid alkaloids

Protalkaloids

They contain nitrogen in a side chain and considered as an alkaloid due to their pharmacological property

Heterocyclic alkaloids

The nitrogen is in a ring structure and chemically considered as an alkaloid

Ephedra/Ma huang (Ephedra sinica)

can be a precursor for Amphetamines

Ephedrine

• constituent of Ephedrine

• for hypotension, nasal decongestion, asthma

Autumn crocus/Saffron meadow (Colchicum autumnale)

Constituent: Colchicine - old DOC for acute gout

Khat/Abyssinian tea (Catha edulis)

constituent: Cathenone

Cathenone

euphoric (Amphetamine-like effect), alleviate hunger

Peyote/Mescal buttons (Lophophora williamsii)

oldest/first phenylalkylamine alkaloid

Mescaline

• constituent of Peyote

• hallucinogenic and psychomimetic

Nicotine (Nicotania tabacum)

• derivative of Pyrrolidone

• smoking deterrent, CNS stimulant - cholinergic

Areca/Betel nut (Areca catechu)

• nganga

• stimulant masticatory, taenicide, anthelminthic (vet)

• high tannin content: risk of mouth and esophageal cancer

Lobelia/Indian tobacco (Lobelia inflata)

Lobeline: less addictive than Nicotine

Belladonna/Deadly nightshade (Atropa belladonna)

Main constituents: Hyoscyamine and Atropine

Atropine

anti-cholinergic, antidote for cholinergic poisoning (used in war)

Hyoscyamine

anti-spasmodic for menstruation

Neostigmine

Atropine antidote

Hyoscyamus/Henbane (Hyoscyamus niger)

Main constituents: Hyoscyamine and Scopolamine

Scopolamine

anti-motion sickness

Egyptian henbane (Hyoscyamus muticus)

contains Hyoscyamine

Talumpunay/Thorn apple (Datura metel)

local source of Scopolamine/Hyoscine

Withania (Withania somnifera)

• main constituents: Tropine, Pseudotropine, Hygrine

• use: sedative

Stramomium/Jimson weed (Datura stramomium)

burned to release the vapor as anti-asthma (burnt weed)

Duboisia (Duboisia myoporoides)

commercial source of Atropine

Pituri/Australian tobacco (Duboisia hopwoodii)

Nicotine, Nornicotine: used like tobacco

Mandragora/European Mandrake (Mandragora officinarum)

Hyoscyamine, Scopolamine, Mandragorine

Erthroxylon coca or Huanuco coca

Coca/Coca leaves/ Divine the plant of Incas

Cocaine

• main constituent of Coca leaves

• prototype of local anesthetic

• only one with vasoconstriction

• MOA: blocks Dopamine reuptake

Brompton’s cocktail

pharmaceutical preparation for pain in cancer patients

Cinchona bark/Peruvian bark

• constituents: Quinine (anti-malaria) and Quinidine (anti-arrhythmic)

• D/I:

Cinchona succirubra

Red cinchona bark

Cinchona calisaya

yellow cinchona/calisaya bark

Cinchonism

• S/E of Cinchona

• tinnitus, dizziness, impaired eyesight

Thalleioquinine reaction

• test for differentiation of Quinine from Quinidine

• (+) Quinidine: emerald green

• (+) Quinine: red

Dita/Australian Quinine Bark (Alstonia scholaris)

main constituent: Ditamine (anti-malaria)

Cupreabark (Remijia purdieana)

commercial source of Quinidine

Papaver somniferum

• Opium Gum/Indian Opium

• S/E: respiratory depression, pinpoint pupils, coma

• stone of immortality

Morphine

most important opium alkaloid

Codeine

• most widely used

• antitussive

Papaverine

smooth muscle relaxant

Anarcotine/Noscapine

partial opium agonist

Paregoric

camphorated opium tincture

Laudanum

opium tincture

Dover’s powder

ipecac + opium

Twilight sleep

scopolamine + morphine

Meconic acid

analytical marker for Opiates

Sanguinaria/Blood root (Sanguinaria canadensis)

• main constituents: Sanguinarine and Chelerythrine

• use: expectorant and cosmetic purposes

Sanguinarine

only red alkaloid

Ipecac (Cephaelis ipecacuanha)

• main constituent: Emetine, Cephaline, Psychotrine

• use: local emetic for poisoning and anti-protozoan (IM)

• MOA: protein synthesis inhibition

Tubocurare/Curare (Strychnos castelnaei)

• main constituent: Tubocurarine

• MOA: non-depolarizing neuromuscular blocker leading to paralysis

• QC test: head drop rabbit test

Snakeroot/Rauwolfia (Rauwolfia serpentina)

• Reserpine → VMAT inh → no catecholamines → hypotension

• use: hypotensive agent with psychotherapeutic effect

Catharanthus/Vinca/Periwinkle (Catharanthus roseus)

• constituent: Vincristine, Vinblastine, Vinorelbine

• MOA: arrest cell division at Metaphase

• use: anti-CA (e.g., Hodgkin’s disease)

Nuxvomica

• seed of Strychnos nux vomica

• constituents: Strychnine (CNS stimulant) and Brucine (alcohol denaturant)

Ignatia/St. Ignatius Bean (Strychnos ignatia)

commercial source of Strychnine (vermin killer)

Physostigma/Calabar/Ordeal bean (Physostigma venenosum)

• constituent: Physostigmine for glaucoma and anti-cholinergic poisoning

• MOA: Acetylcholinesterase inhibition leading to increase effects of ACh

Rye ergot

dried sclerotium of Claviceps purpurea on Rye bread/ Wheat bread

Ergonovine/Ergometrine

oxytocic for postpartum hemorrhage

Ergotamine

for migraine

Ergotoxine

lipid-soluble mixture of Ergocristine, Ergocryptine, Ergoconine

LSD

most potent hallucinogen

Gangrenous ergotism/ St. Anthony’s fire/ Dry ergotism

tissue death due to excessive vasoconstriction

Convulsive ergotism/ Wet ergotism

convulsion associated with Vitamin A deficiency

Pilocarpus/Jaborandi (Pilocarpus jaborandii)

main constituent: Pilocarpine

Pilocarpine

direct muscarinic agonist for glaucoma

Green hellebore (Veratrum viridae)

• insecticide

• effect: slows down heartbeat leading to hypotension

• Germidine, Germitrine

White hellebore (Veratrum album)

• insecticide

• effect: slows down heartbeat leading to hypotension

• Protoveratrine A and Protoveratrine B

Caffeine

• CNS stimulant

• only reacts with Murexide reagent

Theobromine

diuretic for pulmonary edema and CNS stimulant

Theophylline

• for COPD

• MOA: inhibits PDE leading to increase cAMP and NE release

• Natural sources:

  • Cola nuts (Cola nitida)

  • Coffee bean (Coffea arabica) - aroma due to Caffeol

  • Theobroma cacao and Camellia sinensis