Question

Match the LIST-I with LIST-II.

Choose the correct answer from the options given below:

• A. A-IV, B-II, C-I, D-III
• B. A-IV, B-I, C-II, D-III
• C. A-III, B-II, C-I, D-IV
• D. A-IV, B-I, C-III, D-II

Hint:

Identify the functional groups: Glutamine has an amide, Lysine has a primary amine, Tyrosine has a phenol, and Serine has an alcohol. Match these to their standard qualitative tests.

Answer 1

The Correct Option is B

This question tests the knowledge of side-chain functional groups in amino acids and the qualitative organic tests used to identify them.

Step 1: Analyze Glutamine.
Structure: $H_2N-CO-CH_2-CH_2-CH(NH_2)COOH$.
Functional group in side chain: Amide ($-CONH_2$).
Test: Hoffmann bromamide degradation is used to detect/react with amides.
Match: A $\rightarrow$ IV.

Step 2: Analyze Lysine.
Structure: $H_2N-(CH_2)_4-CH(NH_2)COOH$.
Functional group in side chain: Primary amine ($-NH_2$).
Test: Hinsberg's test is the standard reagent (Benzene sulfonyl chloride) for identifying primary amines.
Match: B $\rightarrow$ I.

Step 3: Analyze Tyrosine.
Structure: $HO-C_6H_4-CH_2-CH(NH_2)COOH$.
Functional group in side chain: Phenol ($-OH$ on benzene ring).
Test: Neutral $FeCl_3$ gives a violet/purple coloration with phenols.
Match: C $\rightarrow$ II.

Step 4: Analyze Serine.
Structure: $HO-CH_2-CH(NH_2)COOH$.
Functional group in side chain: Aliphatic alcohol ($-OH$).
Test: Ceric ammonium nitrate (CAN) is used for the detection of alcohols (yellow to red color change).
Match: D $\rightarrow$ III.

Combining these results, the correct sequence is A-IV, B-I, C-II, D-III, which corresponds to option 2.