1. Alkaloids 1 Alkaloids originating from
1-Capsaicinoides (Capsicum annuum [Solanaceae])
Capsaicine:pungent,
iritation on the skin,
rubafecient in
rheumatoid pain
2-Ephedrine, pseudoephedrine (Ephedra sinica)
3-Cathine (Catha edulis)

2. Ephedrine
Ephedra sinica “ma huang”; Used in treatment of common cold, ↑BP and pulse, contraction of blood vessels, bronchodilator, fat combustion Pseudoephedrin vasoconstriction on mucous membranes, rhinitis, Herbal extasy, doping

3. Ephedra alkaloids

4. Khat tea: Catha edulis (Celastraceae)
Leaves: Flav., vol. oils, cathedulins, tannins, cathinone, cathine,…. Young leaves: cathinone;↓hunger and fatigue, increased alertness, general excitement, ↑self-confidence, talkativeness, “constant mild high” AE: inflammation of oral mucosa, gastric disturbances, anorexia, hypertension, impotence

5. Alkaloids 2 Alkaloids originating from -Adrenaline, noradrenaline
-Mescaline
--Isoquinoline alkaloids
---Benzylisoquinoline alkaloids: Opium alkaloids
---Bis-benzyl-isoquinoline alkaloids:Tubocurarin
---Terpenoid tetrahydro-isoquinoline alkaloids: Ipecac alkaloids (Emetine, cephaeline)

6. Alkaloids 2
Alkaloids originating from
Adrenaline

7. Mescalin and Lophophora williamsii (Cactaceae)
Mescal buttons, South American Indians, religious rituals as hallucinogenic [unusual colored hallucinations, flashing lights, euphoria,disturbes normal mental functions. Psychotomimetic]

8. Alkaloids 3
Alkaloids originating from
Colchicine occurs in the seeds and corms; non-basic alkaloid;
Anti-inflammatory; acute attacks of gout; cytotoxic; anti-mitotic
Tox. Symptoms: swallowing difficulties, abdom. pain, ↓BP, muscle cramp, resp. difficulties; Death: resp. arrest, CV collapse
Toxic dose: 10mg; above 40 mg death within 3 days; suicidal attempts

9. Isoquinoline alkaloids and Benzylisoquinoline alkaloids
Basic structures:

10. Papaver somniferum (Papaveraceae)
Opium: alkaloid richest drug
Alkaloids: 20-30%, meconic acid: ~5%; lactic acid: 1-2%; other acids, enzyms, proteins, resins, fats
Morphine alkaloids: thebaine, codeine, morphine
Benzylisoquinoline alkaloids: Papaverine
Phthalidisoquinoline alkaloids: Noscapine (narcotine)
Several semisynthetic derivatives: Ethylmorphine, diacetyl morphine (heroine), apomorphine, hydromorphone, hydrocodone, cotarnine,….

11. Important opium alkaloids
Papaverine
Thebaine Codeine Morphine

12. Opium and morphine
Opium: CNS stimulant, analgesic, hypnotic, narcotic, stimulating / depressing, checks excess peristalsis, pupil contraction;
Crude opium: ~10% morphine (analgesic, sleep inducer, cough treatment)
Powdered/granulated opium:
Laudandum (opium tincture): analgesic, narcotic
Camphorated opium (paregoric): antiperistaltic, diarrhea, dysentery; cough prep.
Dower’s powder (+ ipecac): diophoretic, influenza; sedative ;
Morphine: mental detachment, tolerance, addiction, withdrawal symptoms
CNS: drowsiness, analgesia, euphoria
Pupil: miosis
Respiration: depressant; respiratory arrest
GI: Stomach: HCl↓, small intestine: Biliary and pancreatic juices ↓ (delayed food digestion), large intestine: peristaltic waves↓, tone↑ (spasm, constipation)
Bronchi: large doses (bronchconstriction),
Nausant and emetic effects, habit formation, …..

13. Codeine, thebaine, noscapine and papaverine
Codeine (methylmorphine): most widely used opium alkaloid, antitussive and narcotic analgesic in the liver [-CH3]; (1/10 the potency of morphine); less toxic, less habit formation, little euphoria; constipation on long term use
Thebaine: used primarily for the semi-synthetic production of other drugs, incl. codeine;
Papaverine (not morphinane!): Smooth muscle relaxant, spasmolytic, little analgesic effect; male impotence!
Noscapine (not morphinane!): Antitussive and cough suppressant, no analgesic or narcotic action; teratogenic!; antitumor action
Papaveratum is a mixture of opium alkaloid: morhine (85.5%), codeine (7.8%), papaverine (6.7%); pain relief during surgery; may be combined with hyoscine

14. Semisynthetic and synthetic derivatives of morphine and thebaine
1-Morphine derivatives: codeine, pholcodine, ethylmorphine, hydromorphone, apomorphine, heroine, nalorphine; dextrometorphan, pentazocine, pethidine, fentanyl, methadone, tramadol
Morhine antagonist: naloxone
2-Thebaine derivatives: Codeine, etorphine, buprenorphine, oxymorphone :nalbuphine, naloxone, naltrexone

15. Bis-benzyl-isoquinoline alkaloids: Curare
Dried extract of barks and stems applied to various South American arrow poisons
1-Menispermaceae curare: Chondrodendron tomentosum : Bis-benzyl –THIQ alkaloids; 4-7% alkaloids; d-tubocurarine
2- Loganiaceae curare: Strychnos spp. : Indol alkaloids
3-Mixture of both plants
“Monkey test”; “head drop test”
d-tubocurarine: H2O-sol., monoquaternary NH4-salt;
Paralysis, relaxation of voluntary muscles, competes
with acetylcholine at nicotinic receptors;
death: muscles of respiration stops to operate;
treatment: artificial respiration and specific antidotes:
anti-acetylcholine-esterase drugs: Physostigmine, neostigmine
Uses: Parkinson’s disease, MS, tetanus; skeletal muscle relaxant, surgery Synth. Analogues: deca-, suxa-methonium; atracurium, vencuronium

16. Terpenoid tetrahydro-isoquinoline alkaloids Radix ipecacuanha
Cephaelis ipecacuanha, C. acuminata (Fam. Rubiaceae)
Major alkaloids: emetine and cephaeline
Minor alkaloids: psychotrine and O-methyl-psychotrine
Ipecac: high doses: emetic; small doses: expectorant
Emetine: antiaemebic, anti-protozoan, amebic dysentery, expectorant, antiviral, antitumor; O-methylpsychotrine: AIDS (inhibition of HIV reverse transcriptase)
psychotrine O-methyl-psychotrine