Biosynthetic classification of alkaloids

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1. Biosynthetic classification of alkaloids Presented by : M. Jamal Email: [email protected]

2. Alkaloids “ Basic nitrogenous compound, contains one or more nitrogen in heterocyclic ring system having marked physiological action on human and animals when use in small quantities””. Classification of alkaloids 1. Chemical classification of alkaloids 2. Taxonomical classification of alkaloids 3. Pharmacological classification of alkaloids 4. Biosynthetic classification of alkaloids

3. Common amino acid precursors: Phenylalanine Tyrosine Tryptophan Histidine Anthranilic acid Lysine Ornithine

4. Biosynthetic classification of alkaloids Alkaloids are classified on the basis of biosynthetic precursors from which these are obtained . These include Ornithine derived alkaloids Tryptophan derived alkaloids Lysine derived alkaloids Phenylalanine derived alkaloids Tyrosine derived alkaloids Histidine derived alkaloids Alkaloids derived from substance other than amino acids.

5. Some of the general reactions that are of particular importance include: decarboxylation (removal of carboxyl group or carbon dioxide) and transamination (transfer of an amino group from one molecule to another without the formation of ammonia) of the amino acids to yield a corresponding amine or aldehyde. These can react to form a Schiff base which, in turn can react with carbanion in a Mannich-type condensation. General reactions for biosynthesis of alkaloids

6. Alkaloid formation may require the involvement of only one molecule of amino acid, or 2 molecules of the same AA, or less commonly, 2 molecules of different AA or else several molecules of the same AA.

7. General reaction

8. Ornithine derived alkaloids It includes: Tropane alkaloids Pyrrolidine alkaloids`

9. Tropane alkaloids (Atropine, hyocyamine, hyosine, scopolamine) B.S : Atropa belladona (deadly nightshade), Datura stramonium ( thornapple), Hyosyamus niger (henbane). Family : solanaceae Part used : dried leaves and flowering tops Uses : 1.Atropine is classified as anti cholinergic drugs. Atropine can also be used in SLUDGE syndrome( salivation, lacrimation, urination, diaphoresis, GIT motility and emesis) caused by organophosphate poisoning. Hyoscine is used as antispasmodic. COCAINE B.S : Erythroxylum coca, Erythroxylum novogranatense C ommon name . Coca leaves Family : Erythroxylaceae Part used : Leaves Uses : cocaine is a CNS stimulant. it is also used as local anesthetic.

10. Biosynthesis of tropane alkaloids

11. Tryptophan derived alkaloids These include INDOLE ALKALOIDS QUINOLINE ALKALOIDS

12. Indole alkaloids Physostigma alkaloids Botanical source . Physostigma venonosum Common name : calabar bean Family : Leguminosae Part used : dried ripe seeds Main constituents : physostigmine , isophysostigmine, physovenine. Uses : These are the cholinesterase inhibitors and used as antidote for atropine poisoning. Also used to treat glaucoma. Ergot alkaoids B.S : Claviceps purpurea Family : Hypocreales Part used : Dried sclerotium of the fungus Main constituents : Ergotamine, Ergometrine, Ergocristine Uses : Ergotamine is used to treat migraine and clustur headache. Ergometrine acts as oxytocic agent and also used in post-partal haemorrhage. Vinca alkaloids B.S : Catharanthus roseus Common name : periwinkle Family : Apocynacea Part used: whole plant Constituents : Vincristine, Vinblastine Uses : these alkaloids have anticancer properties. Rauwolfia alkaloids B.S : Rauwolfia serpentina Common name : indian snakeroot Family : Apocyanacea Part used : leaves Constituents : serpentine, reserpine, ajmaline, ajmalacine, Uses : used as antihypertensive and antiarrhythmic agent.

13. Biosynthesis of Vinca alkaloids

14. Quinoline alkaloids B.S: Cinchona Succirubra , C. calisaya, C. officinalis Common name ; Quina Family : Rubiaceae Part used : Dried Bark Constituents : Quinine, quinidine, cinchonine, cinchonidine. Uses : Quinine is a classical antimalarial. Quinidine is used for cardiac arrythmias and atrial fabrillation.

15. Lysine derived alkaloids These include Lobelia spp pepper spp

16. Lobelia alkaloids B.S : Lobelia inflata Common name : indian tobacco Family : Lobeliaceae Part used : dried aerial parts Constituents : lobeline, isolobeline, lobelanine, lobeladine Uses : it is used in chronic bronchitis and spasmodic asthma. lobeline

17. Pepper alkaloids B.S : Piper nigrum Common name : black pepper, kali mirch Part used : dried , unripe fruit Family : Piperaceae Constituents : piperine and piperittene Uses : piper is used as condiment and for chronic bronchitis.

18. Alkaloids derived from Tyrosine Isoquinoline alkaloids papaver alkaloids cephaelis alkaloids

19. Papaver alkaloids B.S : Papaver somniferum Family : papaveraceae Part used : dried milky latex of poppy capsule. constituents : Morphine, codiene, thebaine, Norcotine, Narciene , papaverine Uses : Morphine is used as analgesic. codiene is used in cough preparations. Cephaelis alkaloids B.S : C.ipecacuanha Common name : Ipecac Part used : roots and rhizome Family : Rubiaceae Constituents : cephaline, psychotrine, Emetine, Uses : ipecacuanha is used as expectorant, and emetic and in the treatment of Ameobic dysentry. Emetine

20. BIOSYNTHESIS OF OPIUM ALKALOIDS: ------- L- Dopa ------ Dopamine + 3,4 – dipydroxyphenylpyruvic acid PAPAVERINE ----------------- norlaudanosoline ( ket intermediate) Reticuline Saluteridine Saluteredinol        

21. Alkaloids derived from phenylalanine EPHEDRINE, PSEUDOEPHEDRINE :- B.S –It consists of dried young stem of Ephedra gerardiana and Ephedra nebrodensis . Synonym—Ma- huang ). Family:- Ephedraceae C.C:-- It contains the amino alkaloids : Ephedrine, nor-ephedrine, n-methyl ephedrine, pseudo-ephedrine. Uses: it is used in Asthma, hay fever, flu, cold medications.

22. Biosynthesis of Ephedrine

23. Histidine derived alkaloids These alkaloids include Imidazole alkaloids. e.g Pilocarpine

24. It is used in the treatment of glaucoma and atropine poisoning.

25. Purines are derivatives of a heterocyclic nucleus consisting of a six-membered Pyrimidine ring fused to a five-membered Imidazole ring. Purines are Psudo alkaloids (Are not derived from amino acids but have nitrogen in a heterocyclic ring) Purine alkaloids Alkaloids obtained from precursors other than Amino Acids

26. xanthine theophyilline coffeine theobromine Purine alkaloids They are all methyl derivatives of xanthine.

27. Theobromine B.S. Theobroma cacao Family: sterculiaceae Part used: seeds Uses: Cocoa has nutritive, stimulant and diuretic properties. Theobromine is used as a diuretic. It has less action on the central nervous system than caffeine but is more diuretic.

28. Caffeine B.S: Coffee arabica Family: Rubiaceae Uses: caffeine is used in combinations with antipyretics and analgesics, cold and flu medication . also used as Ingredient in non-alcoholic beverages and “energizing” beverages.

29. END