In the ring structure of fructose, the anomeric carbon is :
Show Hint
- C2
- C3
- C4
- C1
The Correct Option is A
Solution and Explanation
During the cyclization of monosaccharides, a new chiral center is created at the carbon atom that previously contained the carbonyl group (aldehyde or ketone). This newly formed chiral center is called the anomeric carbon.
Step 2: Meaning
Fructose is a ketohexose. Its open-chain linear structure contains a ketone functional group.
Step 3: Analysis
By standard IUPAC numbering rules for carbohydrates, the carbonyl carbon of the ketone group in open-chain fructose is located at position C2. When fructose cyclizes to form a five-membered furanose ring, the oxygen from the C5 hydroxyl group attacks the C2 carbonyl carbon.
Step 4: Conclusion
Because the C2 carbon was the carbonyl carbon in the open chain, it becomes the hemiketal center, making C2 the anomeric carbon in the cyclic structure of fructose.
Final Answer: (A)
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