Phytochemistry Pharmacy Chapter 3 PDF

‫ﺳﻜﻨﺪ )‪(3‬‬ ‫ﺍﻓﻨﺎﻥ ﺍﻟﺰﻗﻴﻠﻲ‬  Oleander glycosides Nerium oleander (Apocynaceae) This group of glycosides, which has an action similar to that of digitalis. Oleander glycosides The principal constituents of the leaves are oleandrin and digitalinum. Oleandrin &digitalinu...

‫ﺳﻜﻨﺪ )‪(3‬‬ ‫ﺍﻓﻨﺎﻥ ﺍﻟﺰﻗﻴﻠﻲ‬  Oleander glycosides Nerium oleander (Apocynaceae) This group of glycosides, which has an action similar to that of digitalis. Oleander glycosides The principal constituents of the leaves are oleandrin and digitalinum. Oleandrin &digitalinum Oleandrin comprising oleandrigenin and L- oleandrose. Other constituents e.g. Uzarigenin, adynerigenin,gitoxigenin and digitoxigenin. Oleandrigenin + L-oleandrose. Uzarigenin , adynerigenin, gitoxigenin, digitoxigenin. Bufadienolides: They are found in some Liliaceae & Ranunculaceae. Squill  Squill Urginea maritima (Liliaceae) Red : Anthocyanin, Scilliroside. Constituents: Scillaren A, B.Flavonoids (Quercetin derivatives and kaempferol) Carbohydrates ( sinistrin) mucilage, calcium oxalate.  Squill Preparation of Scillaren A: Fresh bulbs + ammonium sulfate Tannin solution is added then ext, with ethylacetate The tannin left is precipitated by lead acetate and filtered. Filtrate evaporated to dryness with extracted methnol Conc. and left Scillaren A crystallize out. Chemical test: Scillaren A + acetic anhydride + H2SO4 develops a blood red colour changing gradually to blue and finally bluish green. Sqiull  Cyanophore Glycosides (Cyanogenetic glycosides ) Glycosides yielding hydrocyanic acid. Manihotoxin → Manihot utilissima Amygdalin →bitter almond Linamarin → linseed Phaseolunatin → phaseolus lunatus. Wild cherry bark  Wild cherry bark Prunus serotina (Rosaceae) Shrub or tree. Prunasin enzyme prunase glucose, benzaldehyde, about 0.07-0.16% of HCN. Uses : In cough preparations, ( mild sedative properties and a pleasant taste). Delection of cyanophore glycosides: Drug + 5% alcoholic potash one minute. Transfer it to an 2.5% ferrous sulfate aqueous solution 1% ferric chloride For about 10 mins containing Transfer to 20% HCl. The presence of HCN is indicated by the formation of Prussian blue.  Amygdalin :Found in bitter almond Prunus amygdalus (Rosaceae) , also the kernels of apricots, cherries, peaches and plums. Amygdalin  Preparation : Cake (after the expression of the fixed oil). Ext. with 95 % ethanol. ethanolic extract concentrated to a small volume. Mixed with a large volume of ether. Amygdalin will Crystallise out.  Linamarin Linamarin : occurs in linseed Linum usitatissimum (Linaceae).  Thioglycosides Sometimes called thiocyanate glycosides or sulphurated glycosides. Their aglycones → thiocyanates. Cruciferae, Capparidaceae and Resedaceae. Sinigrin → black mustards seeds. Sinalbin → white mustards seeds. Gluconapin → rape seeds. Mustard seed  Mustard seed Brassica nigra (Cruciferae). Constituents : Sinigrin and myosin, after macceration with water yield 0.7-1.3% of V.oil. The latter contains over 90% of allylisothiocyanate, 27% fixed oil, 30% protein , mucilage and traces of sinapine hydrogen sulphate ( white mustard). Uses: As rubefacients and counterirritant (in the form of plaster ), condiments.  Sinigrin : Is the main constituent of black mustard seeds Brassica nigra (Cruciferae) glucose Myrosin Sinalbin glucose + acrinylisothiocynate + sinapine acid sulfate H2O Pungent taste, less volatile than allylisothiocynate Volatiles oil and Resins  Volatiles oil and Resins Volatile oils are the odorous principles found in various parts. They evaporate when exposed to the air at ordinary temperature , ethereal oils, essential oils. glandular hairs (Labiatae), parenchyma cells (Piperaceae) , Oil – tubes called vittae (Umbelliferae). lysigenous or schizogenous passages (Pinaceae ,Rutaceae).  Volatiles oil and Resins They may be formed directly by Protoplasm , by decomposition of the resinogenous layer of the cell wall , or by the hydrolysis of certain glycosides. Volatiles oil Terpene derivatives Aromatic compounds  Volatiles oil and Resins Physical properties of volatile oils : Odours , immiscible with water, soluble in ether, alcohol and most organic solvents. Volatile - Fixed oils : V.oils → distilled, can not be saponified with alkalies. Do not become rancid (oxidize and resinify). Distillation → Water , water and steam, Direct steam. myrosin Enzymatic hydrolysis Sinigrin V. oil of mustard. Expression (lemon oil, orange oil). Extraction (petroleum ether or benzene)  9.59 in 9.59 in can not be saponified with alkalies 5.6 in 9.42 in Do not become rancid (oxidize and resinify)  Medicnal and commercial uses: Antiseptics, anthelmintics, local stimulants ,diuretics. Spices, flavouring of foods, confections, cosmetics and tobacco. Eleoptene The hydrocarbon portion of the oil , Volatile oils which is liquid generally consist of Stearoptenes The oxidized hydrocarbon portion of the oil , which are usually solid Menthol , thymol and anethol are solid stearoptenes ; eucalyptol , eugenol and methyl salicylate are liquid.  Volatile oils Compounds may be separated in various ways. 1- Low temperature, which crystallize out the stearoptene. 2- Fractional distillation. 3- Fractional crystallization. 4- Gas chromatography. 5- Removal by chemical action (Compounds with free acidic groups may be removed from the oil with sodium carbonate, basic compounds may be removed with hydrochloric acid, phenols with sodium hydroxide, aldehydes with sodium bisulfite ).  Many volatile oils consist largely of terpenes. Terpenes are natural products whose structure may be divided into isoprene units. Isoprene (C5H8) Monoterpenes are composed of 2 isoprene units (C10H16). Sesquiterpenes are composed of 3 isoprene units (C15H24 ). Diterpenes are composed of 4 isoprene units (C20H32 ). Triterpenes are composed of 6 isoprene units (C300H48 ). The Terpenes found most often in volatile oils are monoterpenes. They occur in acyclic and bicyclic forms.  Classification of constituents of volatile oils : 1- Hydrocarbons. 2- Alcohols. 3- Aldehydes. 4- Ketones. 5- Esters. 6- Phenols and phenolic ethers. 7- Oxides. 8- Peroxides. 9- Sulfur compounds. 10- Nitrogen compounds. Resins  Resins Solid, amorphous products of complex chemical nature. On heating they soften and finally melt. Insoluble in water and petroleum spirit but dissolve completely in alcohol, chloroform and ether. Composition: resin acids, resin alcohols (resinols), resin phenol (resinotannols), esters and resenes. Often associated with volatile oils (oleoresins), with gums (gum-resins) or with oil and gum (oleo-gum-resins). Resins may also combined in a glycosidal manner with sugars.