Write down structure of the following compounds:
4-Methylaminobutanoic acid

Explanation

To write down the structure of 4-Methylaminobutanoic acid, we will follow these steps:

### Step 1: Identify the main functional group
The compound is a carboxylic acid, as indicated by the suffix "oic acid." The main functional group is the carboxyl group (-COOH).

**Hint:** Look for the suffix in the name to identify the main functional group.

### Step 2: Determine the carbon chain
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