The IUPAC name of `{:(HO-underset(|)(CH)-COOH),(HO-CH-COOH):}` is:

Options

A. 2,3-Dihydroxybutane-1,4-carboxylic acid
B. 2,3-Dihydroxybutane-1,4-dioic acid
C. 1,2-Dihydroxyethane dicarboxylic acid
D. none of these

Answer

To determine the IUPAC name of the given compound `{:(HO-underset(|)(CH)-COOH),(HO-CH-COOH):}`, we will follow these steps:

### Step 1: Identify the Functional Groups
The compound contains two functional groups:
1. Carboxylic acid (–COOH)
2. Alcohol (–OH)

### Step 2: Determine the Longest Carbon Chain
The longest continuous carbon chain that includes both functional groups is identified. In this case, the longest chain has four carbon atoms (butane).

### Step 3: Number the Carbon Chain
Number the carbon chain starting from the end closest to the functional group that has the highest priority. In this case, the carboxylic acid has higher priority than the alcohol. Therefore, we number the chain as follows:
- Carbon 1: –COOH
- Carbon 2: –OH
- Carbon 3: –OH
- Carbon 4: –COOH

### Step 4: Identify the Positions of the Functional Groups
From the numbering:
- The first –COOH is at position 1.
- The first –OH is at position 2.
- The second –OH is at position 3.
- The second –COOH is at position 4.

### Step 5: Combine the Information
Since we have two –OH groups, we use the prefix "dihydroxy" to indicate their presence. The carboxylic acid suffix will be "dioic acid" since there are two –COOH groups.

### Step 6: Write the IUPAC Name
Putting all the information together, the IUPAC name is:
**2,3-dihydroxybutane-1,4-dioic acid**

### Summary of the Steps:
1. Identify functional groups (carboxylic acid and alcohol).
2. Determine the longest carbon chain (butane).
3. Number the carbon chain (prioritizing the carboxylic acid).
4. Identify positions of functional groups.
5. Combine the information for the name.
6. Write the final IUPAC name.