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

b) Urcinol test “Bial’s test”:

Solution of carbohydrate is heated with on equal volume of conc. HCl

containing little urcinol. Formation of blue color indicates pentose.

6) Test for 2-desoxy sugars “Keller-Kiliani test”: (See latter)

The sugar or the substance containing 2-desoxysugar is dissolved in acetic

acid containing a trace of FeCl3 and transferred to the surface of conc. H2SO4.

At the junction of the liquids a reddish-brown color is produced which gradually

turns into bluish green color.

7) Enzyme reactions:

Certain specific enzymes may be used to identify certain carbohydrates.

8) Chromatography

Chemical Reactions of Simple Sugars “Monosaccharides”

A) As Alcohol:

1. Ester-formation: e.g., Acetates and phosphates. The – OH groups of
monosaccharides can form esters with acids (phosphate & sulfate). Sugar

esters are used to prepare some carbohydrate derivatives.
Phosphate esters:

Phosphate esters can be formed at the 6-carbon of aldohexoses (Glucose – 6 –
phosphate); found in the sugar-phosphate backbone of DNA and RNA, and as

intermediates in the metabolism of carbohydrates in the body.

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