title: The novel acid degradation products of losartan: Isolation and characterization using Q-TOF, 2D-NMR and FTIR.
abstract: Forced degradation of losartan potassium in acidic condition resulted into three potential unknown impurities. These unknown degradation products marked as LD-I, LD-II and LD-III were analyzed using a new reverse-phase high performance liquid chromatography (HPLC), eluting at 3.63, 3.73 and 3.91 relative retention times with respect to losartan potassium (LOS) peak. All three were isolated from reaction mass using preparative HPLC and their structures were elucidated using LC-MS/MS, multidimensional NMR and FTIR spectroscopic techniques, as 5(2),11(2)-dibutyl-5(4),11(4)-dichloro-1(1)H,5(1)H,7(1)H,11(1)H-1(5,1),7(1,5)-ditetrazola-5,11(1,5)-diimidazola-2,8(1,2),3,9(1,4)-tetrabenzenacyclododecaphane,(Z)-5(2),11(2)-dibutyl-5(4),11(4)-dichloro-1(1)H,5(1)H,7(2)H,11(1)H-1(5,1),7(2,5)-ditetrazola-5,11(1,5)-diimidazola-2,8(1,2),3,9(1,4)-tetrabenzenacyclododecaphane, and 5(2),11(2)-dibutyl-5(4),11(4)-dichloro-1(2)H,5(1)H,7(2)H,11(1)H-1(5,2),7(2,5)-ditetrazola-5,11(1,5)-diimidazola-2,8(1,2),3,9(1,4)-tetrabenzenacyclododecaphane, respectively. To best of our knowledge, all three degradation products are novel impurities which are not discussed at any form of publication yet.
authors.affiliation: Analytical Research and Development, United States Pharmacopeial Convention-India (P) Ltd., Plot No. D6 & D8, IKP, Genome Valley, Shameerpet, Hyderabad 500078, India.
authors.forename: Avadhesh
authors.initials: A
authors.lastname: Kumar Pandey
authors.affiliation: Analytical Research and Development, United States Pharmacopeial Convention-India (P) Ltd., Plot No. D6 & D8, IKP, Genome Valley, Shameerpet, Hyderabad 500078, India.
authors.forename: Ravi
authors.initials: R
authors.lastname: Rapolu
authors.affiliation: Analytical Research and Development, United States Pharmacopeial Convention-India (P) Ltd., Plot No. D6 & D8, IKP, Genome Valley, Shameerpet, Hyderabad 500078, India.
authors.forename: Ch Krishnam
authors.initials: ChK
authors.lastname: Raju
authors.affiliation: Analytical Research and Development, United States Pharmacopeial Convention-India (P) Ltd., Plot No. D6 & D8, IKP, Genome Valley, Shameerpet, Hyderabad 500078, India.
authors.forename: Gururaj
authors.initials: G
authors.lastname: Sasalamari
authors.affiliation: Analytical Research and Development, United States Pharmacopeial Convention-India (P) Ltd., Plot No. D6 & D8, IKP, Genome Valley, Shameerpet, Hyderabad 500078, India.
authors.forename: Sanath
authors.initials: S
authors.lastname: Kumar Goud
authors.affiliation: Analytical Research and Development, United States Pharmacopeial Convention-India (P) Ltd., Plot No. D6 & D8, IKP, Genome Valley, Shameerpet, Hyderabad 500078, India. Electronic address: axa@usp.org.
authors.forename: Atul
authors.initials: A
authors.lastname: Awasthi
authors.affiliation: Analytical Research and Development, United States Pharmacopeial Convention-India (P) Ltd., Plot No. D6 & D8, IKP, Genome Valley, Shameerpet, Hyderabad 500078, India.
authors.forename: Sameer G
authors.initials: SG
authors.lastname: Navalgund
authors.affiliation: Analytical Research and Development, United States Pharmacopeial Convention-India (P) Ltd., Plot No. D6 & D8, IKP, Genome Valley, Shameerpet, Hyderabad 500078, India.
authors.forename: Koduru V
authors.initials: KV
authors.lastname: Surendranath
mesh_terms: D000143:Acids / Q000737:chemistry*; D002853:Chromatography, Liquid / Q000379:methods; D004340:Drug Contamination; D019808:Losartan / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D000143:Acids; D019808:Losartan
keywords: Acidic degradation; FTIR; LC-QTOF-MS; Losartan potassium; NMR; Novel impurities