Procyclidine Hydrochloride is a synthetic anticholinergic pharmaceutical active ingredient belonging to the class of centrally acting muscarinic antagonists. It is the hydrochloride salt of procyclidine and is chemically identified as 1-cyclohexyl-1-phenyl-3-pyrrolidin-1-ylpropan-1-ol hydrochloride. The API has the molecular formula C₁₉H₃₀ClNO, corresponding to C₁₉H₂₉NO·HCl, and a molecular weight of 323.90 g/mol. Its CAS Number is 1508-76-5.
Procyclidine Hydrochloride is primarily associated with antiparkinsonian and anticholinergic pharmaceutical applications. It acts as a muscarinic antagonist and has been used to reduce symptoms such as rigidity and tremor associated with parkinsonism and drug-induced extrapyramidal disorders.
The hydrochloride salt is the pharmacopoeial form relevant to pharmaceutical API manufacturing. It should be clearly distinguished from Procyclidine free base (CAS 77-37-2), which has a different molecular weight and formula.
Product Name: Procyclidine Hydrochloride
Synonyms: Procyclidine HCl; Procyclidine Hydrochloride
CAS Number: 1508-76-5
Molecular Formula: C₁₉H₃₀ClNO
Molecular Weight: 323.90 g/mol
API Class: Anticholinergic / Antiparkinsonian API
Chemical Type: Hydrochloride salt
Appearance: White or almost white crystalline powder
Free Base CAS: 77-37-2
USP identifies the API as 1-Pyrrolidinepropanol, α-cyclohexyl-α-phenyl-, hydrochloride.
Procyclidine Hydrochloride contains a tertiary alcohol structure together with cyclohexyl, phenyl and pyrrolidine groups. The hydrochloride salt provides the pharmaceutical form used in established medicinal products.
Procyclidine acts primarily through antagonism of muscarinic cholinergic receptors. Its central anticholinergic activity contributes to its use in parkinsonism and the management of drug-induced extrapyramidal symptoms.
The API is a crystalline solid and is sufficiently water-compatible in its hydrochloride form for pharmaceutical processing. Its chemical identity can be established using infrared spectroscopy, while chloride identification and physical-property testing provide additional confirmation.
Procyclidine Hydrochloride is used as an active pharmaceutical ingredient in medicines intended for parkinsonism and drug-induced extrapyramidal disorders.
Its anticholinergic activity can help reduce motor symptoms associated with excessive cholinergic activity in the central nervous system. Procyclidine Hydrochloride has also been incorporated into pharmaceutical formulations such as tablets and injectable preparations. The British Pharmacopoeia reference-standard documentation specifically identifies Procyclidine Hydrochloride for use with monographs covering Procyclidine Tablets and Procyclidine Injection.
The dosage strength, formulation, route of administration and excipient system depend on the approved finished pharmaceutical product and applicable regulatory requirements.
Procyclidine Hydrochloride has a USP-NF monograph. USP specifies 99.0–101.0%, calculated on the dried basis.
The USP monograph specifies identification by infrared absorption, an additional identification based on the isolated procyclidine melting at 83–87°C, and chloride identification. The pH is specified as 5.0–6.5 in a 1-in-100 solution.
Loss on drying is controlled at NMT 0.5%, with vacuum drying at 105°C for 4 hours. Residue on ignition is NMT 0.1%.
The USP related-compounds procedure uses gas chromatography with flame-ionization detection and specifies total impurities NMT 4.0% by area normalization. Therefore, this test should not be incorrectly entered in the CMS as an HPLC impurity specification.
Procyclidine Hydrochloride API manufacturing requires controlled chemical processing, purification, salt formation, drying and comprehensive analytical testing. A qualified Procyclidine Hydrochloride API manufacturer in India can support pharmaceutical development and commercial production with batch-specific quality documentation.
Manufacturing controls should cover raw-material qualification, reaction and purification parameters, hydrochloride salt formation, drying conditions, physical-property monitoring and final release testing.
Particular attention should be given to API identity, assay, moisture, residue on ignition, pH and related substances. Analytical methods should be validated or appropriately qualified for the intended specification and regulatory application.
Procyclidine Hydrochloride should be protected from moisture, contamination and light using suitable pharmaceutical packaging.
The USP monograph specifies tight, light-resistant containers and storage in a dry place.
The British Pharmacopoeia reference standard is stored under refrigerated conditions of 2–8°C, but this is a reference-standard storage condition and should not automatically be treated as the commercial API storage specification.
Commercial API storage should follow validated stability data and the manufacturer's approved packaging configuration.
Typical documentation for Procyclidine Hydrochloride API may include:
All documentation should clearly state Procyclidine Hydrochloride, CAS 1508-76-5, rather than the free-base CAS 77-37-2.
Procyclidine Hydrochloride is a pharmacopoeially recognized anticholinergic API with defined USP quality requirements. USP specifies 99.0–101.0% assay on the dried basis, NMT 0.5% loss on drying, NMT 0.1% residue on ignition, pH 5.0–6.5 in a 1-in-100 solution, and NMT 4.0% total related impurities by the specified GC procedure.
A qualified Procyclidine Hydrochloride 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) | 99.0–101.0%, |
| Loss on Drying | NMT 0.5% |
| Residue on Ignition | NMT 0.1% |
| pH (1% Solution) | 5.0–6.5 |
| Melting Point | 83–87°C |