Nitrofurantoin Monohydrate is a synthetic nitrofuran antibacterial active pharmaceutical ingredient (API) used primarily in pharmaceutical formulations for urinary tract infections. It is the monohydrate form of nitrofurantoin and contains one molecule of water of crystallization.
FDA identifies Nitrofurantoin Monohydrate with CAS 17140-81-7, molecular formula C₈H₆N₄O₅·H₂O, and molecular weight 256.17 g/mol.
Nitrofurantoin Monohydrate is an important urinary antibacterial pharmaceutical API used in the development and manufacture of oral dosage formulations.
The monohydrate form is distinct from Nitrofurantoin Macrocrystals. In some marketed dosage forms, both forms are used together; however, Nitrofurantoin Monohydrate itself is a specific API form with its own crystalline and hydration characteristics. Current FDA labeling identifies Nitrofurantoin Monohydrate as C₈H₆N₄O₅·H₂O, with molecular weight approximately 256.17 g/mol.
CAS Number: 17140-81-7
Molecular Formula: C₈H₆N₄O₅·H₂O
Equivalent Molecular Formula: C₈H₈N₄O₆
Molecular Weight: 256.17 g/mol
Chemical Name: 1-[[[5-nitro-2-furanyl]methylene]amino]-2,4-imidazolidinedione monohydrate
IUPAC Name: 1-[(Z)-(5-nitrofuran-2-yl)methylideneamino]imidazolidine-2,4-dione;hydrate
Drug Class: Nitrofuran Antibacterial
Therapeutic Class: Urinary Antibacterial
Therapeutic Area: Infectious Diseases / Urology
Molecule Type: Synthetic Small Molecule
Pharmaceutical Form: Monohydrate
Parent Compound: Nitrofurantoin
FDA's substance database and PubChem confirm the monohydrate identity and molecular composition.
Nitrofurantoin is reduced by bacterial flavoproteins to reactive intermediates that damage bacterial cellular components. The resulting activity affects multiple bacterial processes.
Its antibacterial effects include:
Because Nitrofurantoin acts through multiple bacterial targets, it is primarily used as a urinary antibacterial agent.
Nitrofurantoin Monohydrate API is relevant to:
Nitrofurantoin is specifically associated with antibacterial treatment of urinary tract infections. Current FDA labeling describes Nitrofurantoin as an antibacterial agent specific for urinary tract infections.
Its pharmacological use is related to the high urinary exposure achieved after administration, making it particularly suitable for susceptible bacterial infections of the urinary tract.
Nitrofurantoin Monohydrate is a crystalline pharmaceutical substance containing one molecule of water of crystallization. PubChem reports a molecular weight of 256.17 g/mol, while FDA documentation confirms the same molecular formula and molecular weight for the monohydrate form.
Nitrofurantoin has very low aqueous solubility, which contributes to its formulation characteristics. It is substantially more soluble under alkaline conditions than in acidic or neutral aqueous media.
For an API page, solubility should therefore be described as very slightly soluble/practically insoluble in water, rather than assigning a single numerical value unless the test temperature, polymorphic/hydrate form and analytical method are specified.
The monohydrate contains one molecule of water associated with each Nitrofurantoin molecule.
This is important because Nitrofurantoin Monohydrate and Nitrofurantoin Macrocrystals are different physical forms. FDA labeling for combination capsules specifically identifies 75% Nitrofurantoin Monohydrate and 25% Nitrofurantoin Macrocrystals in certain products.
A controlled Nitrofurantoin Monohydrate API manufacturing process may involve:
Typical Nitrofurantoin Monohydrate API testing may include:
Store Nitrofurantoin Monohydrate API in a tightly closed container under controlled pharmaceutical storage conditions, protected from excessive moisture, heat and direct light.
Storage conditions should be established according to validated stability data and the applicable API specification.
Nitrofurantoin Monohydrate is relevant to research involving:
| Parameter | Specification |
|---|---|
| Appearance | White crystalline powder or crystals |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | 6.5% – 7.5% |
| Residue on Ignition | NMT 0.1% |
| Heavy Metals | NMT 20 ppm |
| Individual Impurity | NMT 1.0% |
| Total Impurities | ≤ 1.5% |
| Water Content | 6.5% – 7.5% |
| Melting Point | 270°C – 272°C (decomposes) |