Nitrofurantoin: Chemical Structure, SAR, Mechanism of Action, Synthesis, Uses & Side Effects

Chemical Formula:

• C8H6N4O5

Structure of Nitrofurantoin

SAR:

• Nitrofurantoin is an antibiotic often used for urinary tract infections.

• Its antibacterial activity is believed to be due to the nitro group which, upon reduction by bacterial nitroreductases, produces reactive intermediates that interfere with several bacterial processes, such as protein synthesis, DNA synthesis, and cell wall synthesis.

• The furan ring is essential for the drug's activity.

Mechanism of Action:

• Nitrofurantoin is another nitrofuran derivative antibiotic.

• Its mechanism of action is similar to furazolidone, as it also involves the reduction of the nitro group in the nitrofurantoin molecule by bacterial nitroreductases.

• The reduced intermediates are highly reactive and damage bacterial DNA, proteins, and other macromolecules, resulting in bacterial cell death.

Synthesis:

The synthesis of Nitrofurantoin involves two steps:

1. Condensation of furfural with urea to yield 5-nitrofurfural:

2. Furfural + Urea → 5-Nitrofurfural

3. The 5-nitrofurfural is then reacted with semicarbazide to yield Nitrofurantoin:

4. 5-Nitrofurfural + Semicarbazide → Nitrofurantoin + H2O

Uses:

• Nitrofurantoin is primarily used to treat and prevent urinary tract infections (UTIs) caused by susceptible bacteria, such as Escherichia coli and Staphylococcus saprophyticus.

Side Effects:

Some common side effects of nitrofurantoin include:

• Nausea

• Vomiting

• Diarrhea

• Loss of appetite

• Headache

Serious side effects may include:

• Hypersensitivity reactions

• Hemolytic anaemia (especially in patients with glucose-6-phosphate dehydrogenase deficiency)

• Pulmonary toxicity (acute and chronic)

• Peripheral neuropathy

• Hepatotoxicity