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JEE Main · 2025 · 04 Apr 2025 · Shift 1 · Biomolecules

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Identify the pair of reactants that upon reaction, with elimination of HCl will give rise to the dipeptide Gly-Ala.
  1. (A)(see structure)
    ✓ Correct
  2. (B)(see structure)
  3. (C)(see structure)
  4. (D)(see structure)

Answer: (A)

Solution

In the dipeptide Gly--Ala glycine supplies the nitrogen (amino) end and alanine the carboxyl end, so the peptide bond forms between the carbonyl carbon of glycine and the amino nitrogen of alanine. Losing on coupling requires the glycine carbonyl to be activated as an acid chloride while alanine retains its free amino group, that is reacting with . Their union eliminates and yields , which is Gly--Ala; the required pair is glycyl chloride together with alanine.

JEE Main · 2025 · 04 Apr 2025 · Shift 1 · Single correct option

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