Which of the following compounds contain amide linkage?

Options

A. Nylon-6
B. Acetamide
C. Proteins
D. Cellulose

Answer

To determine which of the given compounds contain amide linkages, we need to understand what an amide linkage is. An amide linkage is characterized by the presence of a carbonyl group (C=O) directly attached to a nitrogen atom (N).

Let's analyze each option step by step:

### Step 1: Analyze Nylon-6
- **Structure**: Nylon-6 is a polymer derived from the monomer caprolactam. Its structure can be represented as CH2(CH2)4C(=O)NH.
- **Linkage**: In this structure, we can see the presence of a carbonyl group (C=O) directly bonded to a nitrogen atom (N).
- **Conclusion**: Therefore, Nylon-6 contains an amide linkage.

### Step 2: Analyze Acetamide
- **Structure**: Acetamide has the formula CH3C(=O)NH2.
- **Linkage**: Here, we also observe a carbonyl group (C=O) attached to a nitrogen atom (N).
- **Conclusion**: Thus, acetamide contains an amide linkage.

### Step 3: Analyze Proteins
- **Structure**: Proteins are polymers made up of amino acids linked by peptide bonds. A peptide bond can be represented as R1C(=O)NR2, where R1 and R2 are side chains of amino acids.
- **Linkage**: The peptide bond, which forms between the amino group of one amino acid and the carboxyl group of another, is indeed an amide linkage.
- **Conclusion**: Therefore, proteins contain amide linkages.

### Step 4: Analyze Cellulose
- **Structure**: Cellulose is a polysaccharide made up of β-D-glucose units.
- **Linkage**: The linkage between glucose units in cellulose is a glycosidic bond, which is characterized by an ether linkage (C-O-C) rather than an amide linkage.
- **Conclusion**: Hence, cellulose does not contain an amide linkage.

### Final Conclusion
- **Compounds with Amide Linkage**: Nylon-6, Acetamide, and Proteins contain amide linkages.
- **Compound without Amide Linkage**: Cellulose does not contain an amide linkage.

### Summary of Answers
1. Nylon-6 - Contains amide linkage.
2. Acetamide - Contains amide linkage.
3. Proteins - Contain amide linkage.
4. Cellulose - Does not contain amide linkage.