Manual phytochemistry alkaloids

2010

Al Azhar University Faculty of Pharmacy Department of Pharmacognosy

Dr. Mazen A. El-Sakka

PHYTOCHEMISTRY (3) ALKALOIDS

Third Edition 2010

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Contents Generalities of Alkaloids ...................................................................................... 7

Definition ................................................................................................................... 7

Classification ............................................................................................................ 8

Distribution ............................................................................................................... 8

Functions of alkaloids in plants ......................................................................... 9

Nomenclature........................................................................................................... 9

Prefixes and suffixes: .......................................................................................... 10

Basicity ..................................................................................................................... 10

Factors that may influence the degree of basicity .......................... 10

Physical properties ............................................................................................... 12

Chemical Properties ............................................................................................. 13

Extraction, purification and separation ........................................................ 18

Selection of alkalis ............................................................................................... 19

Selection of solvents ........................................................................................... 20

Quantitative analysis .......................................................................................... 21

Pharmacological activity of Alkaloids............................................................ 22

ALKALOIDS DERIVED FROM ORNITHINE .................................................... 23

Structure of Tropane Alkaloids ................................................................... 23

Pyrrolidine and Tropane Alkaloids ............................................................. 25

Characterization of alkaloids containing tropane alkaloids .............. 29

Official Solanaceae Containing Tropane Alkaloids ................................... 29

Atropa belladonma ....................................................................................... 29

Drugs in Pharmacy .......................................................................................... 32

Hyoscyamus niger ........................................................................................ 33

Solanaceae that are Industrial Sources of Tropane Alkaloids ............ 34

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Hyoscyamus muticus .................................................................................. 34

Datura metel .................................................................................................. 34

Datura stramonium ..................................................................................... 34

ALKALOIDS CONTAINING ERYTHROXYLACEAE ........................................ 36

Erythroxylum coca ....................................................................................... 36

History .................................................................................................................. 36

Addiction terms ................................................................................................. 37

Conversion to Crack .................................................................................... 41

Pyrrolizidine alkaloids ......................................................................................... 42

Drugs Containing Pyrrolizidine alkaloids ..................................................... 44

Borago officinalis .......................................................................................... 44

Symphytum officinalis ................................................................................ 45

Tussilago farfara ........................................................................................... 46

Quinolizidine Alkaloids ........................................................................................ 47

Lupinus spp. .................................................................................................... 47

ALKALOIDS DERIVED FROM LYSINE ............................................................ 48

Lobelia inflate ................................................................................................ 49

Biosynthesis of Lobeline ................................................................................ 49

Punica granatum........................................................................................... 50

Piperidine Amides :Piperaceae ......................................................................... 52

Piper nigrum ................................................................................................... 52

Alkaloids Derived from Nicotinic Acid ........................................................... 53

PYRIDINE ALKALOIDS .................................................................................... 53

Biosynthesis of Nicotinic acid ...................................................................... 54

Vitamin B3 ...................................................................................................... 55

Tobacco ............................................................................................................ 56

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Facts about Nicotine ........................................................................................ 57

ALKALOIDS DERIVED FROM PHENYALANINE & TYROSINE ................. 58

Phenylethylamines and Simple Tetrahydroisoquinoline Alkaloids 58

Simple Tetrahydroisoquinolines ..................................................................... 69

Lophophora williamsii ................................................................................. 69

Benzyltetrahydroisoqunolines ......................................................................... 70

Biosynthesis........................................................................................................ 70

Modified Benzyltetrahydroisoquinoline Alkaloids ..................................... 71

Papaver somniferum ................................................................................... 73

Opiates/Opioids Chemistry & Mechanism of Action ................................ 77

Antidote ................................................................................................................ 80

Chelidonium majus ...................................................................................... 82

Isolation of Opium Ingredients ....................................................................... 84

Isoquinoline Alkaloids (Phenethylisoquinolines) ...................................... 85

Colchicum autumnale ................................................................................. 85

Terpenoid Tetrahydroisoquinoline Alkaloids .............................................. 86

Amaryllidaceae Alkaloids ................................................................................... 87

ALKALOIDS DERIVED FROM TRYPTOPHAN ................................................ 88

Simple Indole Alkaloids ...................................................................................... 89

Hordeum vulgare .......................................................................................... 89

Simple -Carboline Alkaloids ........................................................................... 90

Peganum harmala ........................................................................................ 90

Terpenoid Indole Alkaloids ............................................................................... 92

Rauwolfia serpentine................................................................................... 92

Catharanthus roseus ................................................................................... 95

Strychnos nux-vomica ................................................................................ 97

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Quinoline Alkaloids .............................................................................................. 98

Pyrroloindole Alkaloids ....................................................................................... 99

Physostigma venenosum ........................................................................... 99

Ergot Alkaloids .................................................................................................... 102

Claviceps purpurea ................................................................................... 102

ALKALOIDS DERIVED FROM ANTHRANILIC ACID ................................ 106

Quinazoline Alkaloids ....................................................................................... 106

Quinoline and Acridine Alkaloids ................................................................. 106

ALKALOIDS D