Which of the following vitamins has isoprene units in its structure

Options

A. Vitamin A
B. Vitamin C
C. Vitamin `B_2`
D. Vitamin D

Answer

To determine which vitamin has isoprene units in its structure, we can follow these steps:

### Step 1: Understand Isoprene Units
Isoprene is a five-carbon compound with the formula C5H8. It serves as the building block for many natural compounds, including certain vitamins.

### Step 2: Identify Vitamins
We need to consider the common vitamins that are known to have isoprene units in their structure. The most notable vitamins that are derived from isoprene units include:
- Vitamin A (Retinol)
- Vitamin E (Tocopherol)
- Vitamin K

### Step 3: Analyze Vitamin A Structure
Vitamin A is known to have a structure that is composed of multiple isoprene units. Specifically, the structure of Vitamin A can be represented as a series of four isoprene units linked together.

### Step 4: Confirm Other Vitamins
- **Vitamin E**: Also contains isoprene units, but its structure is more complex and includes a chromanol ring.
- **Vitamin K**: Contains isoprene units as well, but it is less commonly recognized than Vitamin A.

### Step 5: Conclusion
Among the vitamins listed, Vitamin A is the most straightforward example of a vitamin that has isoprene units in its structure.

### Final Answer
Vitamin A (Retinol) has isoprene units in its structure.

---