Identification, Characterization, and Quantification of Impurities of Safinamide Mesilate: Process-Related Impurities and Degradation Products.
The characterization of process-related impurities and degradation products of safinamide mesilate (SAFM) in bulk drug and a stability-indicating HPLC method for the separation and quantification of all the impurities were investigated. Four process-related impurities (Imp-B, Imp-C, Imp-D, and Imp-E) were found in the SAFM bulk drug. Five degradation products (Imp-A, Imp-C, Imp-D, Imp-E, and Imp-F) were observed in SAFM under oxidative conditions. Imp-C, Imp-D, and Imp-E were also degradation products and process-related impurities. Remarkably, one new compound, identified as (S)-2-[4-(3-fluoro-benzyloxy) benzamido] propanamide (i.e., Imp-D), is being reported here as an impurity for the first time. Furthermore, the structures of the aforementioned impurities were characterized and confirmed via IR, NMR, and MS techniques, and the most probable formation mechanisms of all impurities proposed according to the synthesis route. Optimum separation was achieved on an Inertsil ODS-3 column (250 × 4.6 mm, 5 μm), using 0.1% formic acid in water (pH adjusted to 5.0) and acetonitrile as the mobile phase in gradient mode. The proposed method was found to be stability-indicating, precise, linear, accurate, sensitive, and robust for the quantitation of SAFM and its process-related substances, including its degradation products.
Nanjing Tech University, School of Pharmaceutical Sciences, 5 Xinmofan Rd, Nanjing 210009, Jiangsu Province, People's Republic of China.
Liang
L
Zou
Nanjing Tech University, College of Biotechnology and Pharmaceutical Engineering, Nanjing, People's Republic of China.
Lili
L
Sun
Nanjing Tech University, School of Pharmaceutical Sciences, 5 Xinmofan Rd, Nanjing 210009, Jiangsu Province, People's Republic of China.
Hui
H
Zhang
Nanjing Tech University, School of Pharmaceutical Sciences, 5 Xinmofan Rd, Nanjing 210009, Jiangsu Province, People's Republic of China.
Wenkai
W
Hui
Nanjing Tech University, School of Pharmaceutical Sciences, 5 Xinmofan Rd, Nanjing 210009, Jiangsu Province, People's Republic of China.
Qiaogen
Q
Zou
The University of Nottingham, International Pharmacy School of Pharmacy, Nottingham, United Kingdom.
Zheying
Z
Zhu
D000409:Alanine / Q000031:analogs & derivatives* / Q000032:analysis; D001596:Benzylamines / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D004355:Drug Stability; D008698:Mesylates / Q000032:analysis*
D001596:Benzylamines; D008698:Mesylates; C092797:safinamide; D000409:Alanine