Name Clemastine fumarate
Molecular Formula C21H26ClNO.C4H4O4
Molecular Weight 459.97
CAS Registry Number 14976-57-9
EINECS 239-055-2

White or off-white crystalline powder;
Clarity and color of solution Test solution is colorless or not more intensely colored than Color matching fluid
Melting Point 140~145℃
Identification Infrared AbsorptionTLC
Specific rotation [α]D20 +15°～+18 °(c = 1 in methanol)
PH 3.2～4.2
Loss on drying ≤0.5%
Heavy Metal ≤20ppm
Individual impurity≤ 0.5%
Total Impurities ≤1.0%
Residual solvents 500ppm（Ethanol）
Assay(dried base) 98.0%～102.0%

Second generation H1 receptor antagonists
Antihistamines.