Definition of Alkaloids
- Alkaloids are nitrogen-containing natural compounds, primarily derived from amino acids, known for diverse pharmacological activities and often bitter taste.
Structural Features
- Contain basic nitrogen atoms with complex ring and heterocyclic structures.
Advertisements
Classification of Alkaloids
- Based on biosynthetic origin or structure:
- Pyridine/Piperidine: e.g., Nicotine
- Indole: e.g., Vincristine
- Quinoline/Quinolizidine: e.g., Quinine
- Tropane: e.g., Cocaine, Atropine
- Isoquinoline: e.g., Morphine, Reserpine
- Purine: e.g., Caffeine
Biosynthesis
- Derived from amino acids like ornithine, lysine, tyrosine, and tryptophan through complex enzymatic pathways.
Advertisements
Occurrence in Nature
- Primarily in plants (e.g., Solanaceae, Papaveraceae, Rubiaceae), also in some fungi and animals.
Biological Activities and Uses
- Pharmaceuticals: Medications such as analgesics (morphine), stimulants (caffeine), and anti-malarials (quinine).
- Toxicity: Serve as defense compounds.
- Psychoactive Effects: Affect the central nervous system (e.g., cocaine, LSD).
Advertisements
Examples of Alkaloids
- Caffeine: Stimulant in coffee, tea, cacao.
- Atropine: Tropane alkaloid for nerve agent/pesticide poisoning.
- Quinine: Anti-malarial from cinchona bark.
- Reserpine: Isoquinoline alkaloid used to treat high blood pressure and psychotic disorders.
Thank you for reading from Firsthope's notes, don't forget to check YouTube videos!
