Proguanil Hydrochloride is a pharmaceutical active pharmaceutical ingredient (API) belonging to the biguanide class of antimalarial compounds. It is the hydrochloride salt of Proguanil and is used in pharmaceutical formulations for the prevention and treatment of malaria. Proguanil Hydrochloride is identified by CAS Number 637-32-1, with the molecular formula C11H16ClN5·HCl and molecular weight 290.19 g/mol. WHO describes Proguanil Hydrochloride as a biguanide-type dihydrofolate reductase inhibitor used in antimalarial applications.
Proguanil Hydrochloride is a synthetic antimalarial compound and the hydrochloride salt of Proguanil. It is commonly used in oral pharmaceutical products and is also formulated in combination with other antimalarial agents.
The API is generally described as a white crystalline powder. WHO reference material describes Proguanil Hydrochloride as soluble in water and alcohol, with reported solubilities of approximately 1 part in 110 parts water and 1 part in 40 parts alcohol at 20°C.
Proguanil Hydrochloride has the following chemical characteristics:
The hydrochloride salt should be specified separately from Proguanil free base because the two forms have different molecular weights and chemical compositions.
Proguanil Hydrochloride is primarily used in antimalarial pharmaceutical products. It is particularly relevant to malaria prophylaxis and combination treatment.
Its pharmaceutical applications include:
Proguanil is commonly used in combination with atovaquone in pharmaceutical products intended for malaria prevention and treatment.
Proguanil Hydrochloride acts through the inhibition of folate metabolism in susceptible malaria parasites. Proguanil is metabolized to the active compound cycloguanil, which inhibits the parasite dihydrofolate reductase enzyme. This interferes with folate-dependent metabolic processes required for nucleic-acid synthesis and parasite multiplication.
Quality control of Proguanil Hydrochloride API involves testing for identity, assay, purity, related substances, moisture, inorganic residue, and other applicable quality characteristics.
Typical analytical testing may include:
WHO recognizes Proguanil Hydrochloride as a pharmacopoeial substance, and WHO documentation identifies the International Pharmacopoeia as a source of pharmaceutical specifications and analytical procedures.
Proguanil Hydrochloride API manufacturing requires controlled chemical processing, qualified raw materials, purification, crystallization, drying, and validated analytical testing.
A quality-focused manufacturing process may include:
Manufacturing specifications should be aligned with the applicable pharmacopoeial requirements, regulatory expectations, and customer-specific requirements.
Proguanil Hydrochloride should be stored in suitable, tightly closed pharmaceutical containers under controlled environmental conditions.
WHO reference information describes the substance as a white crystalline powder and reports that aqueous solutions remain stable for several months.
Packaging should protect the API from moisture, contamination, excessive heat, and unsuitable environmental exposure during storage and transportation.
Documentation for Proguanil Hydrochloride API may include:
A reliable Proguanil Hydrochloride API manufacturing source should maintain controlled production processes, validated analytical methods, impurity monitoring, batch traceability, and complete quality documentation.
Proguanil Hydrochloride is an established antimalarial API with applications in malaria prevention and treatment. Consistent manufacturing and analytical control help pharmaceutical manufacturers obtain API material suitable for formulation development and commercial pharmaceutical production.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.5% – 101.0% |
| Loss on Drying | NMT 0.5% |
| Residue on Ignition | NMT 0.1% |
| Melting Point | 238–242°C |