In the ring structure of fructose, the anomeric carbon is: -

Options

A. C-1
B. C-5
C. C-2
D. C-6

Explanation

To determine the anomeric carbon in the ring structure of fructose, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure of Fructose**:
- Fructose is a ketose sugar, meaning it contains a ketone functional group. In its linear form, it has the structure:
\[ \text{CH}_2\text{OH} - \text{C}(\text{O}) - \text{C} - \text{C} - \text{C} - \text{C}(\text{OH}) - \text{CH}_2\text{OH} \]

2. **Draw the Ring Structure**:
- When fructose cyclizes, it forms a five-membered ring known as fructofuranose. The oxygen from the carbonyl group (C=O) bonds with one of the carbons, forming the ring.

3. **Label the Carbons**:
- In the ring structure, label the carbons starting from the oxygen in the ring:
- Carbon 1 (C1) is the carbon that was part of the carbonyl group.
- The other carbons are labeled sequentially up to C5.

4. **Identify the Anomeric Carbon**:
- The anomeric carbon is the carbon that was part of the carbonyl group before the ring formation. In the case of fructose, this is the second carbon (C2) because fructose is a ketose.
- In ketoses, the anomeric carbon is the one adjacent to the carbonyl carbon (C2 in this case).

5. **Conclusion**:
- Therefore, in the ring structure of fructose, the anomeric carbon is C2.

### Final Answer:
The anomeric carbon in the ring structure of fructose is **C2**.