about flavonides

1. Flavonoids
Presented by :- Akshaykumar B. Kadam
M.Pharm 1st year
Dept. P’Chemistry
R.C.P. Kasegaon.
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2. Content
 Introduction
 Classification
 Isolation And Purification
 General method of structural determination
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3. INTRODUCTION :-
 Flavonoids are group of polyphenolic compound, and they are a
class of plant secondary metabolites
 The flavonoids are possessing 15 carbon atoms; 2 benzene ring
joined by a 3 carbon chain having carbon skeleton C6 – C3 - C6.
They are plant pigments and having polar nature, soluble in
methanol and water.
 Flavonoids are found in higher vascular plants,particulary in flowers,leaves
and barks.Also in fruits ,grains and nuts.
OCCURRANCE:-
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4. Flavonoids
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5. Classifications -
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6. GENERAL METHOD OF ISOLATION:-
Plant material,
(Flavones /Flavonol)
Extract hot
water Aqueous
extract PPT
Lead acetate
Filtration
Remove tannins
Aqueous phase
Acidified with HCLSugar free
(Flavones /Flavonol)
Extract with alcohol
Alcoholic phase
(Flavones /Flavonol) Flavonoids
Fractional
crystallization
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7. Purification of flavonoids :-
Dried plant material is extracted with either 70% or 80 % Methanol
Aq. Extract is then concentrated to a small volume and filtered if
necessary
An aliquol of this concentration should be applied on whatman filter paper no. 3
Separation of flavones carried out in the solvent mixture BAW (4:1:5)
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8. Individual bands are eluted and concentrated
Further fraction in water, 5% acetic acid .
Purified in n- butanol – ethanol – water (4:1:2.2)
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9. General method of determination flavones:-
On fusion with alkali, flavones are degraded to a phenol and aromatic acids.
e.g.-
Flavones Phenol Aromatic acid
alkali
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10. 1. Salicylic acid
2.Acetophenone
3. Ortho-hydroxy Acetophenone
4.Benzoic acid
Flavones on boiling with KOH gives 4 different product -
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11. Flavones on boiling with KOH gives 4 different
product -
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