PCOG LAB - Chapter 3 (Alkaloids)

Shikimic Pathway

Pathway involved in Alkaloids

Bitter

Taste of Alkaloids

Insoluble or Sparingly Soluble

Alkaloids are _____ in water

Soluble

Alkaloids (salts) formed in reaction with acids are _____

Ether, Chloroform

Free alkaloids are usually soluble in _____

Insoluble

Alkaloidal salts are _____ in ether, chloroform, or other relatively nonpolar, immiscible solvents

Crystalline

Most alkaloids are _____ solids, few are amorphous

Process A

Process A or B of Stas-Otto Method of Extraction of Alkaloids?

Powdered material containing the alkaloidal salts is moistened with alkaline substances → Combines with acids, tannins and other phenolic substances and sets free the alkaloidal bases; extraction is carried out with organic solvents such as ether or petroleum spirit → Concentrated organic liquid is shaken with aqueous acid and allowed to separate → Alkaloidal salts in aqueous liquid while many impurities remain behind in the organic liquid

Process B

Process A or B of Stas-Otto Method of Extraction of Alkaloids?

• Powdered materials is extracted with water or aqueous alcohol containing dilute acid → +Chloroform or other organic solvents and shaken to remove pigments and unwanted materials → Precipitation of the free alkaloids upon addition of excess alkali → Separation by filtration or by extraction with organic solvents

• Volatile liquid alkaloids → Isolated by distillation; powdered material is extracted with water and aqueous extract is made alkaline with NaHCO3 or NH3 → Alkaloid is distilled off in steam → Collected and purified

True Alkaloids

• Derived from amino acids

• They share a heterocyclic ring with nitrogen

Pseudoalkaloids

• Compounds in which the basic C skeletons of which are not derived from amino acids

• Connected with amino acid pathways

Protoalkaloids

• Compounds in which the N atom derived from an amino acid is not part of the heterocycle

• Have a closed ring

• “Atypical Alkaloids”

Atypical Alkaloids

Other name/term of Protoalkaloids

Alkaloids Derived from Animals

• Beta-carbolines - from tunicates (sea squirts)

• Various poisonous alkaloids from poison dart frogs (ex. golden poison frog: Phyllobates terribilis)

Beta-carbolines

Alkaloids derived from tunicates (sea squirts)

Alkaloids Derived from Fungi

• Muscarine - from fly agaric (Amanita muscaria)

• Ergot Alkaloids - from the ergot fungus (Claviceps purpurea)

• Psilocybin - from psychedelic mushroom (Psilocybe spp.)

Muscarine

Alkaloids derived from fly agaric (Amanita muscaria)

Ergot Alkaloids

Alkaloids derived from ergot fungus (Claviceps purpurea)

Psilocybin

Alkaloids derived from psychedelic mushroom (Psilocybe spp.)

Wolf Bane

AKA Aconite

Aconite

• Arrow Poison in Asia

• Homicidal Agent

• Used in treatment of musculoskeletal pain

Aconite

From Aconitum plants or Monkshood (Aconitum napellus)

Belladonna

• Alkaloid contents (Hyoscamine, Hyoscine, and Atropine)

• Used in sedatives, stimulants, and antipasmadics

Belladonna

From Deadly nightshade (Atropa belladonna)

Belladonna

From Deadly nightshade

Cinchona

• Bark of some species contains Quinine

• Used in Malaria

Cinchona

From Madder family (Rubiaceae)

Coffee

• Most abused

• Acts as CNS stimulant

Coffee

From Coffea arabica

Ipecac

• Emetic, expectorant, diaphoretic

• Used for Treatment of Amoebic Dysentery

Kola

• Used in manufacture of non-alcoholic drinks

• CNS stimulant (has caffeine content)

Kola

From Cola nitida

Nux vomica

• Acts as a bitter

• Increasing appetite

• Stimulates peristalsis in chronic constipation due to atony of the bowel

Nux vomica

From Strychnos nux-vomica, Linn. (Fam. Loganiaceae)

Opium

• Narcotic, analgesic, and sedative action

• Poppy capsules are astringent, somniferous, soporific

• Used as anodyne and emollient

Opium

From Papaver somniferum (Fam. Paparaceae)

Rauwolfia

• Hypnotic, sedative, and hypertensive

• Cures pain due to affections of the bowels

Coca

• Stimulant action on CNS

• Leaves are extensively chewed to relieve hunger and fatigue

• Leaves are also used as cerebral and muscle stimulant

Coca

From Erythroxylon coca (Huanco/Bolivian), Erythroxylon coca var. Spruceanum (Peruvian, Truxillo, or Java coca) also known as Erythroxylon truxillense (Fam. Erythroxylaceae)

Ephedra

• Vasoconstrictor (Ephedrine)

• Anti-allergenic, antiasthmatic, antipasmodic, decongestant, cough suppressant, stimulant

Ephedra

From Ephedria sinica (Fam. Ephadreaceae)

Atis

• Eradication of head lice (dried seeds)

• Tonic and to stop diarrhea (bark decoction)

• Used to alleviate pain during rheumatic baths (leaf decoction)

Atis

From Annona squamosa

Bunga

• Astringent gargle (tincture)

• Headaches, fever, and rheumatism (nut)

• Bowel complaints (young nut)

Bunga

From Areca catechu

Cacao

• Food for the gods

• Ingredient in cosmetic ointments

• Ingredient in pharmacy for coating pills and preparing suppositories

• Used to soften and protect chopped hands and lips

• Also used as a diuretic

Cacao

From Theobroma cacao

Chichirica

• Purgative

• Vermifuge

• Depurative

• Hemostatic (roots)

• Stomach cramps (decoction of young leaves)

• Intestinal parasitism (root decoction)

Chichirica

From Catharanthus roseus

Tabako

• Sedative

• Used in enemas for expelling intestinal worms

• Styptic

Tabako

From Nicotina tobacum

Talampunay

• Anesthetic

• Antiasthmatic

• Antipasmodic

• Antitussive

Talampunay

From Datura metel