https://www.selleckchem.com/products/grazoprevir.html Oxytropis falcata Bunge, known as "the King of Herbs" in Tibetan medicine, is used for treatment of hyperpyrexia, pain, wounds, inflammation and anthrax. However, it is difficult to isolate compound with high-purity from O. falcata because of its complexity. In this work, an efficient method was successfully established for the separation of 3-hydroxy-3-methylglutaryl (HMG) flavonoid glycosides from O. falcata by 2D preparative chromatography (2D-HPLC). An ODS C18 preparative column was used for the first-dimension preparation, and the XCharge C18 preparative column with different separation selectivity to the ODS C18 stationary phase was used for the second-dimension preparation. Four HMG flavonoid glycosides (oxytroflavosides A-D) and two flavonoid glycosides (oxytroflavosides F and G) were separated with purities over 98%. Their structures were elucidated by nuclear magnetic resonance spectroscopy. The 2D-HPLC method used in this study is effective for preparative separation of HMG flavonoid glycosides from O. falcata. Additionally, this method shows great potential for the separation of flavonoid glycosides from other plant extracts. © The Author(s) 2020. Published by Oxford University Press. All rights reserved. For Permissions, please email journals.permissions@oup.com.BACKGROUND Treatment initiation with integrase strand transfer inhibitors (INSTIs) has been associated with excess weight gain. Whether similar gains are seen after switch to INSTI among virologically suppressed persons is less clear. We assessed pre/post-INSTI weight changes from AIDS Clinical Trials Group participants (A5001 and A5322). METHODS Participants who were in follow-up from 1997-2017 and switched to INSTI-based antiretroviral regimens were included. Piecewise linear mixed effects models adjusting for age, sex, race/ethnicity, baseline BMI, nadir and current CD4+ T cell count, smoking, diabetes and follow-up time with suppressed HI