Propantheline Bromide is a synthetic antimuscarinic and anticholinergic pharmaceutical active ingredient belonging to the quaternary ammonium class. It is the bromide salt of propantheline and is chemically identified as N-methyl-N,N-bis(1-methylethyl)-2-[(9H-xanthen-9-ylcarbonyl)oxy]ethylaminium bromide. The API has the molecular formula C₂₃H₃₀BrNO₃, molecular weight 448.39 g/mol, and CAS Number 50-34-0.
Propantheline Bromide acts by competitively antagonizing acetylcholine at muscarinic receptors. Its pharmacological activity reduces smooth-muscle tone and exocrine gland secretions, supporting its historical use in gastrointestinal and other conditions involving excessive cholinergic activity.
The exact API form is important for pharmaceutical manufacturing because Propantheline Bromide is distinct from the free propantheline base. The CAS number, molecular weight and analytical specifications should therefore be associated specifically with the bromide salt.
Product Name: Propantheline Bromide
Synonyms: Propantheline Bromide; Propantheline Hydrobromide; Pro-Banthine
CAS Number: 50-34-0
Molecular Formula: C₂₃H₃₀BrNO₃
Molecular Weight: 448.39 g/mol
API Class: Antimuscarinic / Anticholinergic
Chemical Type: Quaternary ammonium bromide salt
Appearance: White to yellowish-white crystalline powder
Melting Point: About 161°C with decomposition
NIST confirms the molecular formula, molecular weight and CAS Number, while the Japanese Pharmacopoeia describes Propantheline Bromide as a white to yellowish-white crystalline powder.
Propantheline Bromide contains a quaternary ammonium nitrogen and a xanthene-derived ester structure. Its ionic bromide salt form contributes to its pharmaceutical properties and distinguishes it from neutral anticholinergic compounds.
The compound competitively inhibits muscarinic acetylcholine activity at neuroeffector sites. This can reduce exocrine gland secretion and decrease smooth-muscle tone and intestinal motility.
The Japanese Pharmacopoeia describes Propantheline Bromide as very soluble in water, ethanol (95), acetic acid and chloroform, soluble in acetic anhydride, and practically insoluble in diethyl ether.
Propantheline Bromide has been used as an anticholinergic pharmaceutical ingredient in products intended for gastrointestinal disorders involving excessive smooth-muscle activity and secretions.
Its pharmacological profile is associated with reduction of intestinal and gastrointestinal smooth-muscle tone, reduction of exocrine secretions and antispasmodic activity. Propantheline Bromide has also historically been used in pharmaceutical preparations for conditions involving excessive sweating and other cholinergic symptoms.
The final dosage form, strength, route of administration and approved therapeutic indication depend on the finished pharmaceutical product and the applicable regulatory jurisdiction.
Propantheline Bromide has a USP-NF monograph. The current USP definition specifies NLT 98.0% and NMT 102.0%, calculated on the dried basis.
The USP assay is a potentiometric titration with 0.1 N perchloric acid, rather than an HPLC assay. Therefore, the CMS field “Assay (HPLC)” should not incorrectly identify the USP assay as HPLC.
USP specifies loss on drying NMT 0.5% after drying at 105°C for 4 hours and residue on ignition NMT 0.1%.
The USP related-compounds procedure controls Propantheline Bromide Related Compound A at NMT 2.0%, Xanthone at NMT 0.5%, and Xanthanoic Acid at NMT 0.5%. The sum of known and unknown impurities is specified at NMT 3.0%.
The Japanese Pharmacopoeia specifies a pH of 5.0–6.0 for a solution prepared by dissolving 1.0 g of Propantheline Bromide in 50 mL of water, equivalent to a 2% w/v solution. It also specifies a melting point of approximately 161°C with decomposition after drying.
Propantheline Bromide API manufacturing requires controlled chemical processing, purification, bromide salt formation, drying and analytical quality control.
A qualified Propantheline Bromide API manufacturer in India can support pharmaceutical development and commercial production through controlled manufacturing processes and batch-specific quality documentation.
Manufacturing controls should include raw-material qualification, process monitoring, purification, salt formation, drying and final release testing. Particular attention should be given to identity, assay, moisture, residue on ignition, bromide content, pH and related substances.
Propantheline Bromide should be stored in suitable pharmaceutical packaging that protects the material from contamination and environmental exposure.
The USP monograph should be followed for the applicable preservation requirements. For USP reference-standard material, commercial documentation lists storage at 2–8°C, but this reference-standard condition should not automatically be treated as the commercial API storage specification.
Commercial API storage should be based on validated stability data, packaging configuration and the approved product specification.
Typical documentation for Propantheline Bromide API may include:
All documents should clearly identify Propantheline Bromide, CAS 50-34-0.
Propantheline Bromide is a pharmacopoeially recognized anticholinergic API with defined USP quality requirements. USP specifies an assay of 98.0–102.0% on the dried basis, loss on drying NMT 0.5%, residue on ignition NMT 0.1%, and controlled limits for specified related compounds.
A qualified Propantheline Bromide API manufacturer in India can provide pharmaceutical-grade material supported by controlled manufacturing, analytical testing and batch-specific documentation.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 0.5% |
| Residue on Ignition | NMT 0.1% |
| Total Impurities | NMT 1.0% |
| Water Content | NMT 3.0% |
| Melting Point | About 161°C with decomposition |