Write down structure of the following compounds:
4-methoxy-2-butenoic acid

Explanation

To draw the structure of 4-methoxy-2-butenoic acid, follow these steps:

### Step-by-Step Solution:

1. **Identify the Base Chain**:
- The name "butenoic acid" indicates that the base chain is butanoic acid, which consists of 4 carbon atoms (but- refers to 4 carbons).
- The "oic acid" suffix indicates that there is a carboxylic acid group (-COOH) at one end of the chain.

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