Which of the following eract with phenyl hydrazine to give same osazone

Options

A. Glucose
B. Fructose
C. Mannose
D. Galactose

Explanation

To determine which of the following sugars react with phenylhydrazine to give the same osazone, we will analyze the structures of glucose, fructose, mannose, and galactose.

### Step-by-Step Solution:

1. **Understanding Osazone Formation**:
- Osazones are formed when reducing sugars react with phenylhydrazine. The reaction involves the formation of a hydrazone, which subsequently rearranges to form an osazone.
- The key point is that sugars that can isomerize or have similar structures can yield the same osazone.

2. **Analyzing Glucose**:
- The structure of D-glucose is:
```
CHO
|
H-C-OH
|
HO-C-H
|
H-C-OH
|
CH2OH
```
- When glucose reacts with phenylhydrazine, it forms an osazone.

3. **Analyzing Fructose**:
- The structure of D-fructose is:
```
CH2OH
|
C=O
|
H-C-OH
|
H-C-OH
|
CH2OH
```
- Fructose is a ketose, but it can also react with phenylhydrazine to form an osazone. The reaction will yield the same osazone as glucose due to their structural similarities.

4. **Analyzing Mannose**:
- The structure of D-mannose is:
```
CHO
|
H-C-OH
|
HO-C-H
|
HO-C-H
|
CH2OH
```
- Mannose is an epimer of glucose and will form a different osazone when reacted with phenylhydrazine.

5. **Analyzing Galactose**:
- The structure of D-galactose is:
```
CHO
|
H-C-OH
|
HO-C-H
|
H-C-OH
|
CH2OH
```
- Galactose is also an epimer of glucose and will also yield a different osazone.

6. **Conclusion**:
- From the analysis, we see that glucose and fructose will yield the same osazone when reacted with phenylhydrazine, while mannose and galactose will yield different osazones.

### Final Answer:
Glucose and Fructose react with phenylhydrazine to give the same osazone.