Uplc class system

Optical rotations were measured on a P-1020 digital polarimeter (Jasco, Tokyo, Japan) and UV spectra were recorded with MeOH on a UV-2700 spectrophotometer (Shimadzu, Kyoto, Japan). The ¹H, ¹³C, and 2D NMR spectra (500 MHz for ¹H and 125 MHz for ¹³C) were acquired using an DD2 500 MHz NMR spectrometer (Agilent, Santa Clara, CA, USA) with TMS as internal standard. HRESIMS spectra were obtained from a LTQ Orbitrap XL spectrometer (Thermo Scientific, Waltham, MA, USA). Analytical HPLC was performed using a UPLC-class system (Waters, Milford, MA, USA) using a C₁₈ column (1.6 μm, 2.1 mm × 50 mm) equipped with a TUV-detector. Column chromatography (CC) was performed with silica gel (100–200 and 200–300 mesh, Qingdao Haiyang Chemical Factory, Qingdao, China), Lobar LiChroprep RP-18 (40–60 μm, Merck, Darmstadt, Germany), and Sephadex LH-20 (Merck). All the solvents purchased were of analytical grade or HPLC grade.

Optical rotations were measured on a P-1020 digital polarimeter (Jasco, Tokyo, Japan). The ¹H-, ¹³C-, and 2D-NMR spectra were acquired using an Agilent DD2 500 MHz NMR spectrometer (500 MHz for ¹H and 125 MHz for ¹³C), with TMS as an internal standard (Agilent, Santa Clara, CA, USA). Analytical HPLC was performed on a Waters UPLC-class system (Waters, Milford, MA, USA), equipped with a TUV-detector, using a C₁₈ column (1.6 μm, 2.1 mm × 50 mm). Column chromatography (CC) was performed using silica gel (100–200, 200–300 mesh, Qingdao Haiyang Chemical Factory, Qingdao, China), Lobar LiChroprep RP-18 (40–60 μm, Merck, Darmstadt, Germany), and Sephadex LH-20 (Merck) columns. All the solvents used were of analytical grade.