title: Identification and characterization of potential impurities in raloxifene hydrochloride.
abstract: During the synthesis of the bulk drug Raloxifene hydrochloride, eight impurities were observed, four of which were found to be new. All of the impurities were detected using the gradient high performance liquid chromatographic (HPLC) method, whose area percentages ranged from 0.05 to 0.1%. LCMS was performed to identify the mass number of these impurities, and a systematic study was carried out to characterize them. These impurities were synthesized and characterized by spectral data, subjected to co-injection in HPLC, and were found to be matching with the impurities present in the sample. Based on their spectral data (IR, NMR, and Mass), these impurities were characterized as Raloxifene-N-Oxide [Impurity: 1]; EP impurity A [Impurity: 2]; EP impurity B [Impurity: 3]; Raloxifene Dimer [Impurity: 4]; HABT (6-Acetoxy-2-[4-hydroxyphenyl]-1-benzothiophene or 6-Hydroxy-2-[4-acetoxyphenyl]-1-benzothiophene) [Impurity: 5]; PEBE (Methyl[4-[2-(piperidin-1-yl)ethoxy]]benzoate) [Impurity: 6]; HHBA (1-[6-hydroxy-2-(4-hydroxyphenyl)-1-benzothiophen-3-yl]ethanone) [Impurity: 7]; 7-MARLF (7-Acetyl-[6-hydroxy-2-(4-hydroxyphenyl)-1-benzothiophen-3-yl][4-[2-(piperidin-1-yl)ethoxy]phenyl methanone) [Impurity: 8]; of which impurities 5-8 are reported for the first time.
authors.affiliation: Chemical Research & Development, NPNC Division, Orchid Chemicals and Pharmaceutical Limited, Sozhanganallur, Chennai 600 119, Tamilnadu, India.
authors.forename: Reguri Buchi
authors.initials: RB
authors.lastname: Reddy
authors.forename: Thirumani Venkateshwar
authors.initials: TV
authors.lastname: Goud
authors.forename: Nagabushanam
authors.initials: N
authors.lastname: Nagamani
authors.forename: Nutakki Pavan
authors.initials: NP
authors.lastname: Kumar
authors.forename: Anandan
authors.initials: A
authors.lastname: Alagudurai
authors.forename: Raman
authors.initials: R
authors.lastname: Murugan
authors.forename: Kannabiran
authors.initials: K
authors.lastname: Parthasarathy
authors.forename: Vinayagam
authors.initials: V
authors.lastname: Karthikeyan
authors.forename: Perumal
authors.initials: P
authors.lastname: Balaji