Drx 600 instrument

Melting points were obtained on a SGW X-4 micro melting point apparatus (INESA Co., Shanghai, China). Optical rotations were measured on a SGW-533 automatic polarimeter (INESA Co., Shanghai, China). The 1D and 2D NMR spectra were measured with a Bruker DRX-600 instrument (Bruker BioS-pin GmbH Company, Rheinstetten, Germany) with TMS as the internal standard. ESIMS data were recorded on an API QSTAR mass spectrometer (Applied Biosystem/MSD Sciex, Concord, Ontario, Canada); HRESIMS were recorded on a Waters Xevo G2-XS QTof mass spectrometer (USA). ECD spectra were recorded on a JASCO J-810 circular dichroism (CD) spectropolarimeter (JASCO Co., Tokyo, Japan). Column chromatography was performed on silica gel 60 (100–200 mesh, Qingdao Marine Chemical Ltd., Qingdao, China), sephadex LH-20 (GE Healthcare, Uppsala, Sweden), and Develosil ODS (50 μm, Nomura Chemical Co. Ltd., Osaka, Japan). The preparation of TLC was performed on HSGF254 plates (Jiangyou silicone Development Co., Ltd., Yantai, China).

Optical rotations were recorded on an A25700-T digital polarimeter (RUDOLPH, Hackettstown, NJ, USA). IR spectra were obtained using a Thermo Tensor Nicolet-6700 spectrometer (Thermo Optics, Inc., Billerica, MA, USA) with KBr pellets, and 1D and 2D NMR spectra were recorded on a Bruker DRX-600 instrument (600 MHz for ¹H and 150 MHz for ¹³C) with TMS as an internal standard, the deuterated solvent used to solubilize the samples were CD₃OD and CDCl₃.HR-ESI-MS was recorded on an UPLC-Q Exactive MS system (Thermo Fisher, Santa Clara, CA, USA). Silica gel (200–300 mesh (Qingdao Haiyang Chemical Co., Ltd., Qingdao, China) and Sephadex LH-20 (Pharmacia Biotech, Switzerland) were used for the chromatography column. Semi-preparative HPLC was performed on a DIONEX Ultimate 3000 system equipped with a diode array detector and a C18 column (250 mm × 10 mm, 5 μm, YMC Co. Ltd., Kyoto, Japan).