Page 35 - Pharmd general phytochemistry I-Final2024_LEUCTERS
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2- Use of diluent in acetylation method:
This method of acetylation makes use of a diluent (oil of turpentine,
xylene) in order to decrease the dehydrating effect of acetic anhydride.
3- Dehydration method:
This method is based upon splitting off of water from 3ry alcohol. The
amount of water obtained is determined, from which the percentage of 3ry
alcohol may be calculated.
2.2. Terpene Esters:
Esters could be identified directly by saponification of the ester into
alcohol and acid.
1- Esters of aliphatic acids:
Bornyl acetate Source: Peppermint oil.
Source: Pine oil.
2- Esters of aromatic acids:
Benzyl benzoate
Source: Oil derived from balsam peru.
Uses: Used as a fixative in perfume and medicinally for treatment of
scabies. OH
Methyl salicylate OMe
Source: O
Oil of winter green. (Prepared by enzymatic hydrolysis)
O -glu -xyl + H2O OH
OCH3
+ Glu + Xyl
OCH3
O O
Gaultherin (glycoside) Methyl salicylate
Uses: It is used as local irritant and antirheumatic (rubefacient).
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