Which of the following structures represents benzanilide ?

Options

A. `C_6H_5NHCOCH_3`
B. `C_6H_5NHCOC_6H_5`
C. `CH_3NHCOC_6H_5`
D. `CH_3NHCOCH_3`

Explanation

To determine which structure represents benzanilide, we need to understand the definition and structure of benzanilide.

### Step-by-Step Solution:

1. **Understanding Benzanilide**:
- Benzanilide is an anilide, which is the N-phenyl derivative of an amide.
- An amide is a compound derived from a carboxylic acid where the hydroxyl group (-OH) is replaced by an amine group (-NH2).

2. **Identifying Benzamide**:
- The simplest amide derived from benzoic acid is benzamide (C6H5CONH2).
- The structure of benzamide consists of a benzene ring (C6H5) attached to a carbonyl group (C=O) and an amine group (NH2).

3. **Forming Benzanilide**:
- To form benzanilide, we replace one hydrogen atom of the nitrogen in benzamide with another phenyl group (C6H5).
- This means that the structure of benzanilide will have two phenyl groups attached to the nitrogen of the amide.

4. **Writing the Structure**:
- The structure can be represented as:
- C6H5NHCOC6H5
- This indicates that the nitrogen (N) is bonded to a phenyl group (C6H5) and the carbonyl carbon (C=O) is also bonded to another phenyl group (C6H5).

5. **Identifying the Correct Option**:
- Among the given options, we need to find the one that matches the structure C6H5NHCOC6H5.
- Upon reviewing the options, we find that option B corresponds to this structure.

### Conclusion:
- The correct structure that represents benzanilide is option B: C6H5NHCOC6H5.