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Clinical pharmacy PharmD program Third level Phytochemistry-1 (PG-504)

Therefore, the best leaves crop is in autumn when there is maximum of terpenes and biflavones.

III) Chromone Bitter Principles

• Khellin and Visnagin

▪ They are obtained from the fruits of Ammi visnaga, family Apiaceae (Umbelliferae).
Preparation:

▪ The fruits are extracted with ether, concentrated, kept in refrigerator, 3 layers are formed:

1) Upper oily green layer: “remove by suction”.
2) Middle fatty layer: “remove by petrol ether extraction”.

3) Lower crystalline layer containing khellin and visnagin.
• The lower layer is purified by repeated crystallization from methanol to yield khellin.

▪ The mother liquor, i.e., methyl alcohol contains visnagin.
OCH 3 O OCH 3 O OCH 3 O

O O CH 3 O O CH 3 O O CH -O-
2
Glucose
OCH 3
Khellin Visnagin Khellol glucoside

Character of khellin:

▪ Crystalline needles, soluble in organic solvents.

▪ Chemical test: When the powder is mixed with sodium or potassium hydroxide pellets, a rose-red

color is developed.
Uses: 1) Coronary vasodilator, used in angina pectoris.

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