The IUPAC name of `CH_3-underset(CONH_2)underset(|)C=CH-CH_2-underset(OH)underset(|)overset(O)overset(||)C` is

Options

A. 4 - carbamoylpent -3- enoic acid
B. 4 - amido -4- methyl -but -3- enoic acid
C. 3-amido -but-2-enecarboxylic acid
D. 4-carboxy -2-methyl - but -2-enamide

Answer

To determine the IUPAC name of the compound `CH3-C(CONH2)=CH-CH2-C(OH)=O`, we will follow these steps:

### Step 1: Identify the Functional Groups
The compound contains two main functional groups:
1. A carboxylic acid group (-COOH)
2. An amide group (-CONH2)

### Step 2: Determine the Priority of Functional Groups
According to IUPAC nomenclature rules, the carboxylic acid group has a higher priority than the amide group. Therefore, we will number the carbon chain starting from the carboxylic acid group.

### Step 3: Number the Carbon Chain
Starting from the carboxylic acid group, we will number the carbon atoms:
1. COOH (carbon 1)
2. Carbon 2 (attached to COOH)
3. Carbon 3 (attached to carbon 2)
4. Carbon 4 (attached to carbon 3)
5. Carbon 5 (attached to carbon 4)

This gives us a total of 5 carbon atoms in the main chain.

### Step 4: Identify the Substituents
- At carbon 4, we have the amide group (-CONH2), which is referred to as a "carbamide" in IUPAC naming.
- At carbon 3, we have a double bond (C=C).

### Step 5: Construct the Name
The base name is derived from the longest carbon chain which is pentanoic acid (5 carbons with a carboxylic acid). The presence of the double bond indicates that we will use the suffix "-enoic acid".

- The amide group at carbon 4 will be named as "4-carbamoyl".
- The double bond is located between carbon 3 and carbon 4, so we will indicate that with "3-eno".

Putting it all together, the IUPAC name is:
**4-carbamoyl-pent-3-enoic acid**

### Final Answer:
The IUPAC name of the compound is **4-carbamoyl-pent-3-enoic acid**.