Transcript pharmacognosy glycosides 2

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****Side effect:
-dependence
-Photosensitivity
-Electrolyte imbalance( hypertension and hypokalemia)
-Colonic atony.
-Colonic melanoma.
*****Contraindication:
Pregnancy
Breast feeding women.
Children under the age of 12 years old.
*****Drug interaction:
Other laxative.
Cardiac glycoside.
Diuretic steroid.
Antibiotics.
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***Pharmacodynamics and
pharmacokinetics.
Stomach: partial hydrolysis for O-glycoside.
(so large bulk dose is used)
Small intestine:
Absorption for non-polar; smaller Mwt.
Aglycon.
Colon:
Activation by normal flora for both O- and Cglycoside
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***Physicochemical
properties ,
-Combined form are soluble in aqueous alcohol and
chlorinated solvent.
-Free aglycone is soluble in chlorinated solvent and
alcohols.
-Detection for free anthraquinone is done using
borntrager’s test.
-Detection for combined anthraquinone and dimmer
is done using modified borntrager’s test which
uses:
-acid and heat to free O-glycoside.
-Acid, heat and oxidizing agent to oxidatively cleave
C- glycosides.
-Heat and oxidizing agent to oxidatively cleave Cglycosides
4 -Quantitation: done on the principle of borntragers
*******Natural source for anthraquinone
glycosides:
***Senna:
-Botanical source:
Leaveas and legumes of:
Cassia acutifolia
fam. Fabaceae
Cassia angustifolia
-Chemical structure
-Pharmacological activity:
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Sennoside A and B:
-Dianthrone; Bidesmoside, O-glycosides at C-8 and C-8’,
-glucose is the sugar part in β- position.
-C-3 and C-3’ : COOH group.
-C-10 and C-10’ chiral centre where C- linkage
-between anthraquinone dimmer.
- Both are diastereomer for each other.
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***Cascara:
-Botanical source:
Rhamnus purshiana Rhamnaceae
-Chemical structure:
-Pharmacological activity:
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R
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R:-CH2OH
Cascaroside A& B:
-A in β-configuration.
-B in α-configuration
R:-CH3::
Cascaroside C &D:
-C in β-configuration.
-D in α-configuration
Cascaroside A and B:
-monoanthrone; Bidesmoside, O-glycosides at
C-8 and C- glycoside at C-10.
-glucose is the sugar part in β- position at C-8.
-C-3 : CH2OH group.
-C-10 chiral centre where C- linkage of
another Glucose unit.
- Both are enantiomer (mirror image isomer).
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