6224 tof lc ms apparatus

NMR experiments were performed on Bruker 400 FT-NMR spectrometers. TMS was used as an internal standard. High resolution electrospray ionization mass spectra (HR-ESI-MS) carried out on an Agilent Technologies 6224 TOF LC-MS apparatus. Mass spectra were recorded on a Bruker Daltonic micro TOF mass spectrometer. Silica gel (200–300 mesh, Qingdao Marine Chemical, Inc. Qingdao, Shandong, China) and Sephadex LH-20 (20–100 μm, GE Healthcare, Uppsala, Sweden); RP-ODS (50 μm) was purchased from Fuji Silysia Chemical Ltd. Silica. TLC was performed on pre-coated Silica gel 60 F254 plates (20 × 20 cm², 0.25 mm; Merck Chemicals Co., Ltd., Shanghai, China) and RP-18 F254 plates (20 × 20 cm², 0.25 mm; Merck Chemicals Co., Ltd., Shanghai, China). The authentic sugar was bought from Sigma-Aldrich, Schweiz, Switzerland. Reagents were used of analytical grade and purchased from Yuwang Group Co., Ltd. (Yucheng, Shandong, China).

Optical rotations were measured on a WZZ-2B spectropolarimeter. IR spectra were recorded on a NICOLET IR200 FT-IR spectrophotometer. NMR spectra were recorded on a Bruker Avance DRX-400 spectrometer at 400 MHz (¹H) and 100 MHz (¹³C). Chemical shifts were expressed in δ (ppm) referring to TMS. HR-ESI-MS was carried out on an Agilent Technologies 6224 TOF LC-MS apparatus. Purity of compounds were determined by HPLC (Agilent 1200) on a column (Silgreen GH0525046C18A; 250 × 4.6 mml.D., S-5 μm, 12 nm). Apoptosis was discriminated with Beckman Coulter CytoFLEX flow cytometry.