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JEE Main · 2022 · 28 Jul 2022 · Shift 1 · Biomolecules

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For the below given cyclic hemiacetal (X), the correct pyranose structure is:
  1. (A)(see structure)
  2. (B)(see structure)
  3. (C)(see structure)
  4. (D)(see structure)
    ✓ Correct

Answer: (D)

Solution

The cyclic hemiacetal (X) shown is a pyranose form of a sugar. To determine the correct structure, we need to identify the stereochemistry at each carbon, particularly at the anomeric carbon (C1). The correct pyranose structure maintains the proper stereochemistry at all chiral centers and the correct orientation of the hydroxyl group at the anomeric carbon. Option (D) represents the correct pyranose structure with the proper configuration.

JEE Main · 2022 · 28 Jul 2022 · Shift 1 · Single correct option

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