Amoxycillin is semi-synthetic modification of

Options

A. penicillin
B. streptomycin
C. tetracyclin
D. chloroampheniol

Explanation

To solve the question "Amoxycillin is a semi-synthetic modification of", we need to analyze the options provided: penicillin, streptomycin, tetracycline, or chloramphenicol.

### Step-by-Step Solution:

1. **Understanding Amoxicillin**:
- Amoxicillin is an antibiotic that is widely used to treat bacterial infections. It is known for its effectiveness against a variety of bacteria.

2. **Identifying the Parent Compound**:
- Amoxicillin is derived from penicillin. It is important to note that amoxicillin is a semi-synthetic modification, meaning it is chemically altered from its natural precursor.

3. **Comparing Structures**:
- The structure of amoxicillin includes a beta-lactam ring similar to that of penicillin. The modifications in amoxicillin involve changes in the side chains attached to the beta-lactam structure, which enhance its antibacterial properties.

4. **Reviewing Other Options**:
- **Streptomycin**: This is an antibiotic derived from the bacterium Streptomyces griseus and is not related to penicillin.
- **Tetracycline**: This is a different class of antibiotics and does not derive from penicillin.
- **Chloramphenicol**: This is also a distinct antibiotic and does not share a direct structural relationship with penicillin.

5. **Conclusion**:
- Based on the structural relationship and the fact that amoxicillin is a modification of penicillin, the correct answer is that amoxicillin is a semi-synthetic modification of **penicillin**.

### Final Answer:
Amoxicillin is a semi-synthetic modification of **penicillin**.