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- A L K A L O I D S -

INTRODUCTIONAlkaloids are a chemically heterogenous group of natural substance and compose more than6000 basic Nitrogen containing organic compounds which occur in about 15% of all vascularterresterial plants and in more than 150 different plant families. The alkaloids exhibit

diversity of structure and also show an extraordinary spectrum of pharmacological activities.Because of these characters, they are important for chemical,physiological studies,taxonomical studies and biogenetic studies.Introduction Two main source of medicine are,one is synthetic and anotheris naturally occurring. Synthetic drugs show rapid onset of action but havingmore side effects in comparison to naturally occurring drugs. The moderntrend are back to choose natural medicine against synthetic medicine. Naturalsource of drugs are plants, animals, or minerals. About 8000 plants are listedin medicinal uses. In this 1800 in Ayurveda, 1100 in Shiddha, 750 in Unani,300 in Tibetan and 4700 plants are used as traditionally ethno medicinally.The world over the total trade of medicinal plants about 8800-lakhdollar, of which contribution of India in world trade less then 1%.Out of this majority of plants are yet to be study photochemical, estimated ofsuch pants to the extent of 5000 to 6000. Phytochemistry is branch of Chemistry, whichdeals with the study ofchemistry of plants. Where the term phytochemistry is comes out from phyta+ chemistry (phyta plant).Pharmaphytochemistry The word pharmaphytochemistry isderived from

pharmakon drugs phyta plants i.e. chemistry of medicinal substanceinside the plants.Alkaloids Chemistry: Sertuerner in 1806 laid the foundation of AlkaloidsChemistry. It is the branch of Pharma Phyto Chemistry, which deals with thestudy of Alkaloids. He reported isolation ofMorphinefrom opium.What is Alkaloids: Alkaloids means Alkali likes. The Pharmacist

W.Meissner proposed the term Alkaloids in 1819. Acc. to him "Alkaloids(alkali = base, oid=like sub) are basic nitrogenous compd. of plant origin

http://en.wikipedia.org/wiki/Nitrogenhttp://en.wikipedia.org/wiki/Terrestrial_planthttp://en.wikipedia.org/wiki/Spectrumhttp://en.wikipedia.org/wiki/Physiologicalhttp://en.wikipedia.org/wiki/Physiologicalhttp://www.ccsu.edu/counseling/New/marijuana/synthetic_drugs.htmchttp://en.wikipedia.org/wiki/Ayurvedahttp://www.siddhamedicine.com/http://www.lifepositive.com/body/traditional-therapies/unani.asphttp://www.tibetanmedicine.com/http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1563446http://en.wikipedia.org/wiki/Phytochemistryhttp://c/Documents%20and%20Settings/yoooooooooo/My%20Documents/Untitled-1.htmlhttp://en.wikipedia.org/wiki/Morphinehttp://en.wikipedia.org/wiki/Morphinehttp://en.wikipedia.org/wiki/Opiumhttp://en.wikipedia.org/wiki/Terrestrial_planthttp://en.wikipedia.org/wiki/Spectrumhttp://en.wikipedia.org/wiki/Physiologicalhttp://www.ccsu.edu/counseling/New/marijuana/synthetic_drugs.htmchttp://en.wikipedia.org/wiki/Ayurvedahttp://www.siddhamedicine.com/http://www.lifepositive.com/body/traditional-therapies/unani.asphttp://www.tibetanmedicine.com/http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1563446http://en.wikipedia.org/wiki/Phytochemistryhttp://c/Documents%20and%20Settings/yoooooooooo/My%20Documents/Untitled-1.htmlhttp://en.wikipedia.org/wiki/Morphinehttp://en.wikipedia.org/wiki/Opiumhttp://en.wikipedia.org/wiki/Nitrogen

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which have complex molecular structure & many pharmacological activity."Acc to Landenberg "Alkaloids are defined as natural plant compoundsthat have a basic character and contain at least one nitrogen atom in aheterocyclic ring and having biological activities."Acc to characteristic features Alkaloidsare basic nitrogenous plant

origin, mostly optically active & possessingnitrogen hetero cycles as therestructural units with physiological action.

Contents

1 HISTORY

2 DEFINITION

3 OCCURRENCE OF ALKALOIDS

4 NOMENCLATURE

5 PROPERTIES

6 CHEMICAL TESTS FOR ALKALOIDS

7 CLASSIFICTION OF ALKALOIDS

http://en.wikipedia.org/wiki/Bioactivehttp://www.organic-chemistry.org/Highlights/2006/24April.shtmhttp://www.organic-chemistry.org/Highlights/2006/24April.shtmhttp://dictionary.die.net/physiological%20timehttp://shekhar-alk.blogspot.in/http://en.wikipedia.org/wiki/Bioactivehttp://www.organic-chemistry.org/Highlights/2006/24April.shtmhttp://dictionary.die.net/physiological%20time

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8 ISOLATION AND EXTRACTION OF ALKALOIDS

9 GENERAL METHODS FOR STRUCTURE DETERMINATION

10 ROLE_OF_ALKALOIDS_IN_PLANTS

HISTORY

The term alkaloids or Pflanzenlkalien was coined by Meissner, a German pharmacist, in1819. the mankind has been using alkaloids for various purposes like poison, medicine,poultices, teas, etcThe French chemist, Derosne in 1803, isolated narcotine. In the same year, morphine fromopium was isolated by Serturner, a pharmacist of Padeborn near hannover in 1803. Pelletierand Caventon from the Faculty of pharmacy of Paris isolated emetine in 1817 andcolchicinesin 1819. this was followed by isolation of series of alkaloids from vegetable drug,like strychnine (1817); brucine, piperine and caffine (1819), quinine, colchicines andcinchonine (1820); coniine (1826), papaverine(1821) and thebaine (1835). By 1884, about

25 alkaloids were reported to be isolated from cinchona bark alone. But in 1870, a landmarkin domain of alkaloid was achieved by determining thestructure of coniine, which also

become first synthesized alkaloid in 1889. From the beginning of 19th century till to date, ithas proved to be a perpetual work of discover new alkaloids from the plant and animal. In the

present century, the proper structure were assigned to various alkaloids with the help ofchromatographic and another sophisticated physical method of analysis. As per a Russianreview in 1973, the number of known alkaloids had reached upto 4959, amongst which, thestructure of 3293 alkaloids were elucidate. At present, the number of alkaloids discovered hasexceeded 6000.

DEFINITION

In the view of their chemical and physiological diversity, there is no comprehensivedefinition of alkaloids. The term is derived from the word alkali-like and hence, theyresemble some of the characters of naturally occurring complex amines. The term alkaloidsalso cover proto alkaloids and pseudoalksloids. In view of all such variations, the only

http://en.wikipedia.org/wiki/Poulticehttp://www.chemdel.com/products/narcotine.htmhttp://en.wikipedia.org/wiki/Emetinehttp://www.merriam-webster.com/dictionary/colchicineshttp://www.merriam-webster.com/dictionary/colchicineshttp://en.wikipedia.org/wiki/Strychninehttp://en.wikipedia.org/wiki/Brucinehttp://en.wikipedia.org/wiki/Piperinehttp://en.wikipedia.org/wiki/Caffeinehttp://en.wikipedia.org/wiki/Quininehttp://en.wikipedia.org/wiki/Colchicineshttp://en.wikipedia.org/wiki/Cinchoninehttp://en.wikipedia.org/wiki/Coniinehttp://en.wikipedia.org/wiki/Papaverinehttp://en.wikipedia.org/wiki/Thebainehttp://en.wikipedia.org/wiki/Cinchonahttp://www.kgv.edu.hk/science/hemlock.jpghttp://www.answers.com/topic/chromatographyhttp://en.wikipedia.org/wiki/Poulticehttp://www.chemdel.com/products/narcotine.htmhttp://en.wikipedia.org/wiki/Emetinehttp://www.merriam-webster.com/dictionary/colchicineshttp://en.wikipedia.org/wiki/Strychninehttp://en.wikipedia.org/wiki/Brucinehttp://en.wikipedia.org/wiki/Piperinehttp://en.wikipedia.org/wiki/Caffeinehttp://en.wikipedia.org/wiki/Quininehttp://en.wikipedia.org/wiki/Colchicineshttp://en.wikipedia.org/wiki/Cinchoninehttp://en.wikipedia.org/wiki/Coniinehttp://en.wikipedia.org/wiki/Papaverinehttp://en.wikipedia.org/wiki/Thebainehttp://en.wikipedia.org/wiki/Cinchonahttp://www.kgv.edu.hk/science/hemlock.jpghttp://www.answers.com/topic/chromatography

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definition that bring all such compounds under one title is as follows:These are the organic product of natural and synthetic origin which are basic in natureand contain one or more than one nitrogen compound normally in heterocyclic innature, and posses specific physiological action on human and animal body, when use insmall quantities

The true alkaloids are toxic in nature and contain one or more heterocyclic nitrogencompound which is derived from amines and always basic in nature. True alkaloids arenormally present in plants as salts of organic acids. The proto-alkaloids or amino-alkaloids inwhich nitrogen is not present in heterocyclic ring.Some times they are considered as biological amines. They are basic in nature and preparedin plants from amino acids. Some of the examples of these alkaloids are mescaline, N-dimethyl tryptamine, colchine and ephedrine. The term pseudoalkaloid includes mainlysteroidal terpenoides alkaloids and purine. They are not derived from amino acids. They donot show many of typical characters of alkaloids, but give the standard qualitative test foralkaloids. The example of pseudoalkaloids are conessine and caffine.

OCCURRENCE OFALKALOIDS

Alkaloids are chemically nitrogenous heterocyclic basic compound occur innature, about15% of vascular plant & widely distributed in higher plant e.g.. -Apocynace, papaveraceae, papilanaceae, rananeulaceae, solenaceae.They are present in the form of salts of organic acid, like acetic acid,oxalic acid, malic, lactic, tartaric, tannic, aconitic acid, few are with sugar e.g.Solanum, veratrum groups. Acc. to parts of plants:

Leaves: Nicotine

Bark: Cinchonine, Quinine.

Seeds: Strychnine, Nibidine.

Roots: Rawelfinine, Glycyrrhizin, Punarnavine I & II

NOMENCLATURE

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There was no systematic nomenclature. But there are some methods fornomenclature are mention below.

According to their source:

There are named according to the family in which they are found e.g. papavarine,punarnavin, ephedrin.

According to their Physiological response:

There are named according to their physiological response e.g.. Morphine means Godof dreams, emetine means to vomit.

According to there discover:

There are named according to there discover e.g.. pelletierine group has been namedits discoverer, P.J. Pelletier.

Prefixes:

There are named by some prefixes are fix in nomenclature of alkaloids, e.g. epi, iso,neo, pseudo, nor- CH3 group not attach to Nitrogen 4

PROPERTIES

PHYSICAL PROPERTIES

With few exemptions, all the alkaloids are colourless, crystalline solids with a sharp meltingpoints or decomposition range. Some alkaloids are amorphous gum, while other coniine,spartine, nicotine etc. are liquid and volatile in naruer. Some alkaloids are coloured in nature,eg. Betanidin is red, berberine is yellow and salts are copper-red in colour.In general, the free bases of alkaloids are soluble in organic non-polar, immiscible solvents.The salts of more alkaloids are soluble in water. In contrast, free bases are insoluble in waterand their salts are also sparingly soluble in organic solvents. The alkaloids containingquaternary bases are only water soluble. Some of the pseudoalkalods and protoalkaloidsshows higher solubility in water. For examples, colchicines is soluble in alkaline water, acidand water and caffeine (free base) is freely soluble in water. Quinine hydrochloride is highlysoluble in water i.e. 1 part of quinine hydrochloride is soluble in less than 1 part of water,

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while only 1 part of quinine sulphate in 1000 parts of water.The solubility of alkaloids and salts is useful in pharmaceutical industry for the extraction andformulation of final pharmaceutical properties

CHEMICAL PROPERTIES

Most of the alkaloids are basic in reaction, due to availability of lone pair of electron on thenitrogen ring. The basic character of the alkaloidal compound is enhanced if the adjust

function groups are electron releasing. The alkaloid turns to be natural or acidic when theadjust functional groups are electron withdrawing like amide group which reducesavailability of lone pair of electrons. But alkaloids exhibits basic characters are very muchsensitive to decomposition and cause a problem during their storage. Their salt formationwith inorganic acid prevents many a time their decomposition.The alkaloids may contain one or more number of nitrogen and it may exist in the form as

primary(R-NH2), eg. Mescaline, secondary amine (R2-NH),eg.ephedrine; tertiary amine(R3-N),eg. Atropine; and quaternary amine (R4N+X),eg. Tubocuarine chloride. In the last type,their properties vary from other alkaloids, owing to quaternary nature of nitrogen.In the natural for, the alkaloids exist either in free form , as amine or as salt with acid oralkaloids N-oxides

CHEMICAL TESTS FORALKALOIDS

The qualitative chemical tests used for detection of alkaloids are depend on the character ofalkaloids to give precipitate as salts of organic acids or with compound of heavy metals likeHg, Au, Pt, etc.

Test by Dragendorff reagent(Potassium-bismuth-iodide solution) : -

Alkaloids give reddish-brown precipitate with this reagent.

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test by Mayer reagent (Potassium-mercuric-iodide solution): -

Alkaloids gives cream colour precipitate with this reagent.

test by Wagner reagent (iodine-potassium-iodide solution): -

Alkaloids give Brown colour precipitate with this reagent.

test by Hager reagent (Saturated solution of picric acid): -

alkaloids give yellow colour precipitate with this reagent.

Test by Tannic acid: -

Alkaloids gives buff colour precipitate with this acid

Test by Picrolonic acid: -

Alkaloids give yellow colour precipitate with this acid

CLASSIFICTION_OF_ALKALOIDS

The other methods proposed for classification of alkalids are as follows: -

PHARMACOLOGICAL CLASSIFICATION: -

Depending on the physiological response, the alkaloids are classified under variouspharmacological categories, like central nervous system stimulants or depressants,symphatomimentics, analgesic, purgative, etc. this method dose not take into accountchemical nature of crude drugs with in the same drugs, the individual alkaloid mayexhibit different action e.g. morphine is narcotic analgesic, while codenine is mainlyantiussive. In cinchona, quinine is antimalarial, while quinidine is cardiac depressant.

TAXONOMIC CLASSIFICATION: -

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This method classifies the vast number of alkaloids based on their distribution invarious plants families, like solanaceous or papillionaceous alkaloids. Preferably, theyare grouped as per the name of genus in which they occur, e.g. ephedra, cinchona, etc.from this classification the chemotaxonomic classification has been further derived.

CHEMICAL CLASSIFICATION: -

This is a most accepted way of classification of alkaloids. The main criterion forchemical classification is the type of fundamental(normally heterocyclic) ringstructure present in alkaloids. The alkaloidal drugs are broadly categorized into twodivisions.

True alkaloids(heterocyclic alkaloids) are divided into twelve group according to thenature of their heterocyclic ring

Protoalkaloids or biological amine and pseudoalkaloids.

Other modes of classification are: -

TAXONOMIC BASED ON THEIR FAMILY: -

e.g. Solanaceous,Papilionaceous without reference their chemical type of alkaloidspresent & another according to genus. e.g.. ephedra, cinchona etc. Pharmacologicalbased: Their pharmacological activity or response. For example:1. Analgesic alkaloids2. Cardio active alkaloids etc. Do not have chemical similarity in their group.

BIO SYNTHETIC CLASSIFICATION: -

This method gives significance to the precious from which the alkaloids are biosynthesized inthe plant. Hence, the varity of alkaloids with different taxonomic distribution and

physiological activities can be brought under same group if they are derived from same

procedure. E.g. all indole alkaloids from tryptophan are grouped together. The alkaloidaldrugs are catagorised on the fact whether are derived from amino acid procedure as ornithine,

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lysine, tyrosine, phenylalanine, tryptophen, etc.According to this alkaloids are usuallyclassified by their common molecular precursors, based on the metabolic pathwayused toconstruct the molecule. When not much was known about thebiosynthesisof alkaloids, theywere grouped under the names of known compounds, even some non-nitrogenous ones (sincethose molecules' structures appear in the finished product; the opium alkaloids are sometimes

called "phenanthrenes", for example), or by the plants or animals they were isolated from.When more is learned about a certain alkaloid, the grouping is changed to reflect the newknowledge, usually taking the name of a biologically-important amine that stands out in thesynthesis process.

Pyridine group:piperine,coniine,trigonelline,arecaidine,guvacine,pilocarpine,cytisine,nicotine,sparteine,pelletierine.

Pyrrolidine group: hygrine,cuscohygrine,nicotine

Tropane group: atropine, cocaine,ecgonine,scopolamine,catuabine

Quinoline group: quinine,quinidine, dihydroquinine, dihydroquinidine,strychnine,brucine, veratrine, cevadine

Isoquinoline group: The opium alkaloids (morphine, codeine,thebaine, Isopapa-dimethoxy-aniline,papaverine, narcotine,sanguinarine,narceine,hydrastine,

berberine), emetine, berbamine,oxyacanthine

Phenethylamine group: mescaline,ephedrine, dopamine,amphetamine

Indole group:

Tryptamines: DMT,N-methyltryptamine,psilocybin, serotonin

Ergolines: the ergot alkaloids (ergine, ergotamine, lysergic acid, LSD etc.

Beta-carbolines: harmine, harmaline, yohimbine,reserpine

Rauwolfia alkaloids: Reserpine

Purine group:

http://en.wikipedia.org/wiki/Metabolic_pathwayhttp://en.wikipedia.org/wiki/Metabolic_pathwayhttp://en.wikipedia.org/wiki/Metabolic_pathwayhttp://en.wikipedia.org/wiki/Metabolic_pathwayhttp://en.wikipedia.org/wiki/Pyridinehttp://en.wikipedia.org/wiki/Piperinehttp://en.wikipedia.org/wiki/Piperinehttp://en.wikipedia.org/wiki/Coniinehttp://en.wikipedia.org/wiki/Trigonellinehttp://en.wikipedia.org/wiki/Trigonellinehttp://en.wikipedia.org/w/index.php?title=Arecaidine&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Arecaidine&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Guvacine&action=edit&redlink=1http://en.wikipedia.org/wiki/Pilocarpinehttp://en.wikipedia.org/wiki/Pilocarpinehttp://en.wikipedia.org/wiki/Cytisinehttp://en.wikipedia.org/wiki/Cytisinehttp://en.wikipedia.org/wiki/Nicotinehttp://en.wikipedia.org/wiki/Sparteinehttp://en.wikipedia.org/wiki/Sparteinehttp://en.wikipedia.org/wiki/Sparteinehttp://en.wikipedia.org/w/index.php?title=Pelletierine&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Pelletierine&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Pelletierine&action=edit&redlink=1http://en.wikipedia.org/wiki/Pyrrolidinehttp://en.wikipedia.org/wiki/Hygrinehttp://en.wikipedia.org/wiki/Cuscohygrinehttp://en.wikipedia.org/wiki/Nicotinehttp://en.wikipedia.org/wiki/Tropanehttp://en.wikipedia.org/wiki/Atropinehttp://en.wikipedia.org/wiki/Cocainehttp://en.wikipedia.org/wiki/Cocainehttp://en.wikipedia.org/wiki/Ecgoninehttp://en.wikipedia.org/wiki/Scopolaminehttp://en.wikipedia.org/wiki/Scopolaminehttp://en.wikipedia.org/wiki/Scopolaminehttp://en.wikipedia.org/wiki/Catuabinehttp://en.wikipedia.org/wiki/Quinolinehttp://en.wikipedia.org/wiki/Quininehttp://en.wikipedia.org/wiki/Quinidinehttp://en.wikipedia.org/wiki/Quinidinehttp://en.wikipedia.org/wiki/Tropanehttp://en.wikipedia.org/wiki/Dihydroquininehttp://en.wikipedia.org/wiki/Strychninehttp://en.wikipedia.org/wiki/Brucinehttp://en.wikipedia.org/wiki/Veratrinehttp://en.wikipedia.org/w/index.php?title=Cevadine&action=edit&redlink=1http://en.wikipedia.org/wiki/Isoquinolinehttp://en.wikipedia.org/wiki/Opiumhttp://en.wikipedia.org/wiki/Morphinehttp://en.wikipedia.org/wiki/Codeinehttp://en.wikipedia.org/wiki/Codeinehttp://en.wikipedia.org/wiki/Thebainehttp://en.wikipedia.org/w/index.php?title=Isopapa-dimethoxy-aniline&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Isopapa-dimethoxy-aniline&action=edit&redlink=1http://en.wikipedia.org/wiki/Papaverinehttp://en.wikipedia.org/wiki/Narcotinehttp://en.wikipedia.org/wiki/Narcotinehttp://en.wikipedia.org/wiki/Sanguinarinehttp://en.wikipedia.org/w/index.php?title=Narceine&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Narceine&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Narceine&action=edit&redlink=1http://en.wikipedia.org/wiki/Hydrastinehttp://en.wikipedia.org/wiki/Hydrastinehttp://en.wikipedia.org/wiki/Berberinehttp://en.wikipedia.org/wiki/Emetinehttp://en.wikipedia.org/wiki/Emetinehttp://en.wikipedia.org/wiki/Phenethylaminehttp://en.wikipedia.org/wiki/Mescalinehttp://en.wikipedia.org/wiki/Ephedrinehttp://en.wikipedia.org/wiki/Ephedrinehttp://en.wikipedia.org/wiki/Dopaminehttp://en.wikipedia.org/wiki/Dopaminehttp://en.wikipedia.org/wiki/Amphetaminehttp://en.wikipedia.org/wiki/Indolehttp://en.wikipedia.org/wiki/Phenethylaminehttp://en.wikipedia.org/wiki/Tryptaminehttp://en.wikipedia.org/wiki/N-methyltryptaminehttp://en.wikipedia.org/wiki/Psilocybinhttp://en.wikipedia.org/wiki/Serotoninhttp://en.wikipedia.org/wiki/Ergolinehttp://en.wikipedia.org/wiki/Ergothttp://en.wikipedia.org/wiki/Erginehttp://en.wikipedia.org/wiki/Phenethylaminehttp://en.wikipedia.org/wiki/Lysergic_acidhttp://en.wikipedia.org/wiki/LSDhttp://en.wikipedia.org/wiki/Beta-carbolinehttp://en.wikipedia.org/wiki/Harminehttp://en.wikipedia.org/wiki/Harmala_alkaloidhttp://en.wikipedia.org/wiki/Yohimbinehttp://en.wikipedia.org/wiki/Yohimbinehttp://shekhar-alk.blogspot.in/2008_08_01_archive.htmlhttp://shekhar-alk.blogspot.in/2008_08_01_archive.htmlhttp://en.wikipedia.org/wiki/Reserpinehttp://en.wikipedia.org/wiki/Purinehttp://en.wikipedia.org/wiki/Metabolic_pathwayhttp://en.wikipedia.org/wiki/Metabolic_pathwayhttp://en.wikipedia.org/wiki/Pyridinehttp://en.wikipedia.org/wiki/Piperinehttp://en.wikipedia.org/wiki/Coniinehttp://en.wikipedia.org/wiki/Trigonellinehttp://en.wikipedia.org/w/index.php?title=Arecaidine&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Guvacine&action=edit&redlink=1http://en.wikipedia.org/wiki/Pilocarpinehttp://en.wikipedia.org/wiki/Cytisinehttp://en.wikipedia.org/wiki/Nicotinehttp://en.wikipedia.org/wiki/Sparteinehttp://en.wikipedia.org/wiki/Sparteinehttp://en.wikipedia.org/w/index.php?title=Pelletierine&action=edit&redlink=1http://en.wikipedia.org/wiki/Pyrrolidinehttp://en.wikipedia.org/wiki/Hygrinehttp://en.wikipedia.org/wiki/Cuscohygrinehttp://en.wikipedia.org/wiki/Nicotinehttp://en.wikipedia.org/wiki/Tropanehttp://en.wikipedia.org/wiki/Atropinehttp://en.wikipedia.org/wiki/Cocainehttp://en.wikipedia.org/wiki/Ecgoninehttp://en.wikipedia.org/wiki/Scopolaminehttp://en.wikipedia.org/wiki/Catuabinehttp://en.wikipedia.org/wiki/Quinolinehttp://en.wikipedia.org/wiki/Quininehttp://en.wikipedia.org/wiki/Quinidinehttp://en.wikipedia.org/wiki/Tropanehttp://en.wikipedia.org/wiki/Dihydroquininehttp://en.wikipedia.org/wiki/Strychninehttp://en.wikipedia.org/wiki/Brucinehttp://en.wikipedia.org/wiki/Veratrinehttp://en.wikipedia.org/w/index.php?title=Cevadine&action=edit&redlink=1http://en.wikipedia.org/wiki/Isoquinolinehttp://en.wikipedia.org/wiki/Opiumhttp://en.wikipedia.org/wiki/Morphinehttp://en.wikipedia.org/wiki/Codeinehttp://en.wikipedia.org/wiki/Thebainehttp://en.wikipedia.org/w/index.php?title=Isopapa-dimethoxy-aniline&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Isopapa-dimethoxy-aniline&action=edit&redlink=1http://en.wikipedia.org/wiki/Papaverinehttp://en.wikipedia.org/wiki/Narcotinehttp://en.wikipedia.org/wiki/Sanguinarinehttp://en.wikipedia.org/w/index.php?title=Narceine&action=edit&redlink=1http://en.wikipedia.org/wiki/Hydrastinehttp://en.wikipedia.org/wiki/Berberinehttp://en.wikipedia.org/wiki/Emetinehttp://en.wikipedia.org/wiki/Phenethylaminehttp://en.wikipedia.org/wiki/Mescalinehttp://en.wikipedia.org/wiki/Ephedrinehttp://en.wikipedia.org/wiki/Dopaminehttp://en.wikipedia.org/wiki/Amphetaminehttp://en.wikipedia.org/wiki/Indolehttp://en.wikipedia.org/wiki/Phenethylaminehttp://en.wikipedia.org/wiki/Tryptaminehttp://en.wikipedia.org/wiki/N-methyltryptaminehttp://en.wikipedia.org/wiki/Psilocybinhttp://en.wikipedia.org/wiki/Serotoninhttp://en.wikipedia.org/wiki/Ergolinehttp://en.wikipedia.org/wiki/Ergothttp://en.wikipedia.org/wiki/Erginehttp://en.wikipedia.org/wiki/Phenethylaminehttp://en.wikipedia.org/wiki/Lysergic_acidhttp://en.wikipedia.org/wiki/LSDhttp://en.wikipedia.org/wiki/Beta-carbolinehttp://en.wikipedia.org/wiki/Harminehttp://en.wikipedia.org/wiki/Harmala_alkaloidhttp://en.wikipedia.org/wiki/Yohimbinehttp://shekhar-alk.blogspot.in/2008_08_01_archive.htmlhttp://shekhar-alk.blogspot.in/2008_08_01_archive.htmlhttp://en.wikipedia.org/wiki/Reserpinehttp://en.wikipedia.org/wiki/Purine

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Xanthines: caffeine, theobromine,theophylline

Terpenoid group:

Aconite alkaloids: aconitine

Steroids: solanine, samandaris (quaternary ammonium compounds):

muscarine,choline,neurine

Vinca alkaloids: vinblastine, vincristine. They are antineoplastic and binds freetubulin dimers thereby disrupting balance between microtuble polymerization anddelpolymerization resulting in arrest of cells in metaphase.

Miscellaneous: capsaicin,cynarin,phytolaccine,phytolaccotoxin

Chemical classification:

This classification is universally adopted & dependson the fundamental ring structure. According to these two main groups.

1. Non-heterocyclic Alkaloids: In this group of alkaloid not has any oneHeterocyclic ring in their structure. e.g.- Hordinine (Hordeum vulgare),Ephedrine(Ephedra gerardiana) Genateceae.

2. Heterocyclic Alkaloids: According to heterocyclic ring the alkaloids aresub divide in following: -

PYRROLE

: This type of alkaloids contains pyroll or pyrrolidine ring in their structure e.g..Hygrines Coca sp. For detailed informationclick here

http://en.wikipedia.org/wiki/Xanthinehttp://en.wikipedia.org/wiki/Caffeinehttp://en.wikipedia.org/wiki/Theobrominehttp://en.wikipedia.org/wiki/Theobrominehttp://en.wikipedia.org/wiki/Theophyllinehttp://en.wikipedia.org/wiki/Terpenoidhttp://en.wikipedia.org/wiki/Aconitehttp://en.wikipedia.org/wiki/Aconitinehttp://en.wikipedia.org/wiki/Steroidhttp://en.wikipedia.org/wiki/Solaninehttp://en.wikipedia.org/w/index.php?title=Samandari&action=edit&redlink=1http://en.wikipedia.org/wiki/Ammoniumhttp://en.wikipedia.org/wiki/Muscarinehttp://en.wikipedia.org/wiki/Muscarinehttp://en.wikipedia.org/wiki/Cholinehttp://en.wikipedia.org/wiki/Neurinehttp://en.wikipedia.org/wiki/Neurinehttp://en.wikipedia.org/wiki/Vinca_alkaloidshttp://en.wikipedia.org/wiki/Vinblastinehttp://en.wikipedia.org/wiki/Vincristinehttp://en.wikipedia.org/wiki/Capsaicinhttp://en.wikipedia.org/wiki/Capsaicinhttp://en.wikipedia.org/w/index.php?title=Cynarin&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Cynarin&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Phytolaccine&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Phytolaccotoxin&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Phytolaccotoxin&action=edit&redlink=1http://en.wikipedia.org/wiki/Pyrrolehttp://en.wikipedia.org/wiki/Pyrrolehttp://en.wikipedia.org/wiki/Xanthinehttp://en.wikipedia.org/wiki/Caffeinehttp://en.wikipedia.org/wiki/Theobrominehttp://en.wikipedia.org/wiki/Theophyllinehttp://en.wikipedia.org/wiki/Terpenoidhttp://en.wikipedia.org/wiki/Aconitehttp://en.wikipedia.org/wiki/Aconitinehttp://en.wikipedia.org/wiki/Steroidhttp://en.wikipedia.org/wiki/Solaninehttp://en.wikipedia.org/w/index.php?title=Samandari&action=edit&redlink=1http://en.wikipedia.org/wiki/Ammoniumhttp://en.wikipedia.org/wiki/Muscarinehttp://en.wikipedia.org/wiki/Cholinehttp://en.wikipedia.org/wiki/Neurinehttp://en.wikipedia.org/wiki/Vinca_alkaloidshttp://en.wikipedia.org/wiki/Vinblastinehttp://en.wikipedia.org/wiki/Vincristinehttp://en.wikipedia.org/wiki/Capsaicinhttp://en.wikipedia.org/w/index.php?title=Cynarin&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Phytolaccine&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Phytolaccotoxin&action=edit&redlink=1http://en.wikipedia.org/wiki/Pyrrole

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PYRROLIZIDINE

Alkaloids containing Pyrrolizidine Heterocyclic ring in their structure e.g.. -seneciphylline Senecio sp. For detailed information click here

PYRIDINE & PIPERIDINE

Alkaloids containing Pyridine Heterocyclic ring in their structure e.g. Nicotine,Lobaline, Piperidine, Ricinine. For detailed information click here&click here

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PIPERIDINE(TROPANE)

Alkaloid containing tropone ring. e.g..-Hyoscyomine, Atropine Hyoscine- SolanceaeCocain- Coca sp. Tropane Quinoline Iso Quinoline Nor Lupinane Iodole For detailedinformation click here ortropane

http://en.wikipedia.org/wiki/Pyrrolehttp://en.wikipedia.org/wiki/Pyridinehttp://en.wikipedia.org/wiki/Piperidinehttp://en.wikipedia.org/wiki/Piperidinehttp://en.wikipedia.org/wiki/Tropanehttp://en.wikipedia.org/wiki/Tropanehttp://shekhar-alk.blogspot.in/http://shekhar-alk.blogspot.in/http://shekhar-alk.blogspot.in/http://shekhar-alk.blogspot.in/http://en.wikipedia.org/wiki/Pyrrolehttp://en.wikipedia.org/wiki/Pyridinehttp://en.wikipedia.org/wiki/Piperidinehttp://en.wikipedia.org/wiki/Piperidinehttp://en.wikipedia.org/wiki/Tropane

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QUINOLINE

Those Alkaloids containing quinolin ring in their structure e.g..- Quinine, Quinidine.(Cinchona bark) Cinchonine, Cinchonidine & cusparin -(cusparia bark) For detailedinformation click here

ISO QUINOLINE

Alkaloids containing iso quinoline ring in thier chemical structure e.g. Papavarine,Narceine Emetine & cephaline. (Cephalis sp Rubiaceae). For detailed information

click here

REDUSED ISO QUINOLINE(APORPHINE)

The alkaloid contain reduced isoquinoline ring in their structure e.g. Baldine, (PeumusBaldus) (Manioniaceae) For detailed information click here

NOR LUPINANE

Alkaloids present in leguminoceae plants e.g. spartine, lupanine.

INDOLE ALKALOIDS

http://en.wikipedia.org/wiki/Quinolinehttp://en.wikipedia.org/wiki/Isoquinolinehttp://en.wikipedia.org/wiki/Aporphinehttp://shekhar-alk.blogspot.in/http://shekhar-alk.blogspot.in/http://shekhar-alk.blogspot.in/http://en.wikipedia.org/wiki/Quinolinehttp://en.wikipedia.org/wiki/Isoquinolinehttp://en.wikipedia.org/wiki/Aporphine

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Alkaloids containing indole ring. e.g. Yohimbine, Aspidospermine (Apocynaceae)Vinblasine, vincristine (catheranthus roseus). For detailed information click here

ISOLATION ANDEXTRACTION OF

ALKALOIDS

The extraction of alkaloids is based upon their basic character and solubility pattern. Thenormal procedures followed are to treat moistened drug with alkali so as to set free the baseas it exists in salt form and then to separate free base with organic solvent. This is known asStas Otto process. Through the method of extraction vary, gernally following procedure isapplied for small scale extraction of alkaloids. First the plant is defatted with patrollium ether,eapatially in case of seed and leaf forms of drugs. Before applying this treatment the alkaloidshould be tested for its solubility in patrolleum ether. Otherwise the drug should be pretreatedwith acid to be convert alkaloid into the salts. This happens in case of extraction ofregotamine from ergot.

In the second stage the drugs may be extacted with polar solvents like water, ehanol, methnolaqueous alcohol mixture or with acidified aqueous solution. By this treatment alkaloidal saltsare transferred to polar solvent. It also helps in remving pigments sugar and other organicconstituents in the following stage. The alcohol solution is evaporated to a thick syrup and issubjected to partition between aqueous acid solution and an organic solvent. After continousextraction with organic solvent for some time the aqueous phase is made alkaline with ethersodium carbonate or ammonia. The basic aqueous solution is then extracted with convenientorganic solvent followed by drying off alkaloid containing solution normally with sodiumsulphate, filtered and evaporated to yield alkaloid residue.The other method ment for extraction for alkaloids employs the treatment of drug withammonia so as to covert the alkaloidal salt into their free bases such librated alkaloids in free

base form are conveniently extracted with organic solvents like ether, benzene, chloroform,etc. the method is not useful for isolating alkaloids with quaternary nitrogen.

http://en.wikipedia.org/wiki/Indole_alkaloidshttp://shekhar-alk.blogspot.in/http://en.wikipedia.org/wiki/Indole_alkaloids

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The further purification of crude extract of alkaloids is done by following ways which mayhowever, vary for indivisual for alkaloids.

Purification or isolation of alkaloids from a plant is always difficult processbecause an alkaloids bearing plant generally contains a complex mixture ofseveral alkaloids with glycoside organic acid also complicate the process.Following steps are involved in isolation process.

Detection of presence of Alkaloids:

First of all confirm the presence ofalkaloids in raw material or crud drugs by various reagents called Alkaloids

reagents e.g.

a,Mayer (Cream Co lour) Test

b.Marquis (Conc. HCHO) Test.

c.Erdmann (Conc. HNO3) Test

d.Hager's (Yellow Colour) Test

e.Frohdes (Molybdic acid) Test

Extraction: -

The plants is dried, then finally powdered and extracted withboiling methanol. The solvent is distilled offand the residue treated with

inorganic acids, when the bases (alkaloids) are extracted as their soluble salts.The aqueous layer containing the salt of alkaloids and soluble plant impuritiesis made basic with NaOH. The insoluble alkaloids are set free precipitate out.The solid man (ppt.) so obtained is then extracted with ether when alkaloid

pass into solution and impurity left behind. Flow Chart of extraction: -

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Separation of Alkaloids:

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After detection of next step is separation of a relatively small percentage of alkaloidsfrom large amount of crude drugs. E.g.- Opium contains 10% Morphine, Chinconacontains 5-8 % Quinine, Belladona- 0.2% of Hyoscyamine.The required alkaloid is separated from the mixture from fractional, crystallization,chromatography and ion exchange method.

PHYSICAL PROPERTIES

They are colorless, crystalline solid. Exception - Berberin (Yellow), Nicotine

Coniine (liquid).

They are insoluble in water (exception liquid alkaloids soluble in water),

soluble in organic solvent ( CHCl3, Ethyl alcohol ether)

Taste: They are bitter in taste.

Optically active, Most of levo ratatory but few are -Dextro rotatory e.g.

Coniine, some inactive- e.g.- papaverine.

GENERAL METHODSFOR STRUCTURE

DETERMINATIONMolecular formula of majority of Alkaloids is complex so very little achievement intheir elucidation of structure. During 19th Century. Now general procedures for

elucidation of structure of alkaloids are adopted.

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Molecular formula molecular weight:

A pure specimen of alkaloids its empirical formula and molecular weight byelemental or combustion analysis. No. Of double bond is determined by double bond

equivalent method.

Number of Double bond: -

Number of Rings present in an alkaloids can be determine by following formula- CaHb Nc Od Then number of double bond present in Ring= a-b/2 + C/2 + 1

Functional group Analysis:

1. Functional Nature of Oxygen: -

Oxygen presents in alkaloids as: -OH (Phenolic/ Alcoholic), - OCH3 Methoxy, - OCOCH3 (Acetoxy), - OCOC6H5(Benzoxyl), -COOH (Carboxylic),- COOK (carboxylate),>C=O (Carbonyl),=C-O-O(Lactones Ring).It can be determined by infra red or organic analysis method.

2. Hydroxyl group: -

Formation of Acetate on treatment with Acetic anhydride /Acetyl chloride or benzoateon treatment with Benzyl chloride.

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Soluble in NaOH

Re precipitated by CO2

Giving coloration with FeCl3

3. Carboxylic group: -

Soluble in aqueous solution sodium carbonate or ammonia on treat with alcohol form

ester.Number of -COOH group can be determined by volumetrically by titrationagainst a standard. Ba(OH)2 solution by using phenolphthalein as an indicator.

4. Oxo-group: -

On treatment with Hydroxylamine. Semicanbezide, phenylhydrazide ,oxime,semicarbazone phenyl Hydrazine

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The distinction between aldehyde and ketone is done by oxidation orreduction, also by NMR, IR, and UV techniques.

4. Methoxyle group: -

BY Zeisel determination method. When methoxy group present in a alkaloids treatedwith HI at 126 0 C perform methyl iodide which can treated further with silver nitritesto perform silver iodide precipitate. Which estimated gravimetrically e.g.. Papavarine.

5. Methylenedioxy group: -

On heated with concentrated with HCL or H2SO4 to form formaldehyde and further

formation of dime done derivative, which estimated gravimetrically.

b) Ester Amide lacton & Lactum group:These groups are identified by the estimation of product.

c) Nature of NitrogenMajority of nitrogen presence in alkaloids are secondary and tertiary: If tertiary whentreated with H2 O2 (50%) form.

If alkaloids react with one molecule of methyl-iodide to form N-methyl

derivative, it means secondary e.g.

1.DIRECT CRYSTALLISATION FROM SOLVENT: -

it is a very simple method of isolation and may not be useful in case of complexmixture

2. STEAM DISTILLATION: -

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This method is espateially employed for volatile liquid alcohols like coniine,sparteine, and nicotine, but other wise this process is not suitable for alcohols withhigh molecular weights.

3. CHROMATOGRAPHY TECHNIQUES: -

This method has provided to be ideal for separation of a vast number of plantalkaloids. The different technique of chromatography (thin layer, column, gas, liquid,ion exchange chromatography, HPTLC, etc.) are used for separation of indivisualalkaloids from complex mixture.

4. GRADIENT pH TECHNIQUES: -

Tthough alkaloids are basic in nature, there are variations in the extent in the basicity

of various alkaloids of the same plant. Depending on this character, the crudealkaloidal mixture is dissolved in 2% tartaric acid solution and extracted with benzeneso that the first fraction contains natural and/or very weakly basic alkaloids. pH of theaqueous solution is increased gradually by 0.5 increment upto pH 9, and extraction iscarried out at each pH level with organic solvent, by this way alkaloids with different

basicity are extracted. Strongly basic alkaloids are extracted at the end.

ROLE OF ALKALOIDSIN PLANTS

The alkaloids are poisonous in nature, but when used in small quantities, exert useful

physiological effects on animals and human beings and hence they have securedsignificant place in medicine. There exact role in nature and function in the plants, ifany, are still a topic ambiguity. Only one aspect is clearly understood that they aresynthesized by particular, stereospecific, many a time complicated, and energyconsuming pathways and further they are metabolized to other alkaloidal or non-alkaloidal substances. Some of the predicted roles of alkaloids in the plants arediscussed below: -

They are the reserve substance with an ability to supply nitrogen.

http://en.wikipedia.org/wiki/Stereospecifichttp://en.wikipedia.org/wiki/Stereospecific

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They might be the defensive mechanism for plant growing in dry regions to

protect from grazing animals, herbivores and insects.

It is also possible that they are end product of detoxification mechanism in

plants, and by this way check formation substance which may prove to beharmful to the plants.

They might have a possible role as growth regulatory factors in plants

The are present normally in conjugation with plants acids, like meconic acid,

cinchotannic acid etc. there foe alkaloids could be acting as carriers with inplants for transportation of such acids