Structure Elucidation and Mechanistic Study of a New Dimeric Degradant in Ropinirole Hydrochloride Extended-Release Tablets

Structural elucidation of two novel degradants of lurasidone and their formation mechanisms under free radical‐mediated oxidative and photolytic conditions via liquid chromatography‐photodiode array/ultraviolet‐tandem mass spectrometry and one‐dimensional/two‐dimensional nuclear magnetic resonance spectroscopy

“…Two novel degradation products were observed under free radical‐mediated oxidative (via AIBN) and solution photolytic conditions. The two previously unknown degradants were investigated via an approach combining LC‐PDA/UV‐MS n ( n = 1, 2), mechanism‐based stress studies, and NMR, a strategy that has been successfully utilized in our laboratories for rapidly identifying degradant structures and elucidating their plausible formation mechanisms 7–19 …”

“…The two previously unknown degradants were investigated via an approach combining LC-PDA/UV-MS n (n = 1, 2), mechanism-based stress studies, and NMR, a strategy that has been successfully utilized in our laboratories for rapidly identifying degradant structures and elucidating their plausible formation mechanisms. [7][8][9][10][11][12][13][14][15][16][17][18][19] We now report the process of identifying the structures of the two novel degradants, and propose their possible formation mechanisms. At the same time, the different oxidative degradation behaviors under the free radical-mediated oxidative condition and nucleophilic oxidative condition are compared and the implication is discussed.…”