How many chiral C - atoms are present in Cimetidine.

Answer

To determine how many chiral carbon (C) atoms are present in Cimetidine, we need to analyze its molecular structure and identify the carbon atoms that meet the criteria for chirality.

### Step-by-Step Solution:

1. **Understanding Chirality**: A carbon atom is considered chiral if it is bonded to four different groups. This means that no two groups attached to the carbon atom can be the same.

2. **Drawing the Structure of Cimetidine**: The molecular formula of Cimetidine is C10H16N6S. The structure includes a thiourea group and a furan ring.

3. **Identifying Carbon Atoms**: In the structure, identify all the carbon atoms present. Cimetidine has several carbon atoms, but we need to focus on those that could potentially be chiral.

4. **Analyzing Each Carbon Atom**:
- Check each carbon atom to see if it is bonded to four different groups.
- For example, if a carbon is bonded to two hydrogen atoms and a methyl group, it is not chiral.
- Conversely, if a carbon is bonded to a methyl group, an ethyl group, a hydrogen atom, and a nitrogen atom, it would be considered chiral.

5. **Counting Chiral Carbons**: After analyzing the structure of Cimetidine:
- Identify which carbon atoms are chiral based on the criteria mentioned.
- In Cimetidine, there are two chiral carbon atoms.

6. **Conclusion**: The total number of chiral carbon atoms in Cimetidine is **2**.

### Final Answer:
Cimetidine has **2 chiral carbon atoms**.