Mcp 500 spectropolarimeter

HRESIMS data were collected on an MAT95XP machine (Thermo Fisher Scientific, Bremen, Germany). NMR spectra were acquired by an Avance-600 spectrometer (Bruker, Fällanden, Switzerland). Circular dichroism (CD) spectra were afforded by a Jasco 820 spectropolarimeter (Jasco Corporation, Kyoto, Japan). Optical rotations were obtained by an MCP-500 spectropolarimeter (Anton Paar, Graz, Austria). UV spectra were acquired using a UV-2600 spectrophotometer (Shimadzu, Kyoto, Japan). IR data were done with an Affinity-1 spectrometer (Shimadzu, Kyoto, Japan). Preparative HPLC was performed using an ODS-A column (250 × 20 mm, 5 μm, 12 nm, YMC Co., Ltd, Kyoto, Japan). An ODS-A/AQ column (250 × 10 mm, 5 μm, 12 nm, YMC CO., Ltd, Kyoto, Japan) was used for semipreparative HPLC separation and the CHIRALPAK IC column (250 × 10 mm, 5 μm) for chiral semipreparative HPLC separation. Silica gel (100–200 and 200-300 mesh, Qingdao Marine Chemical Inc., Qingdao, China), C₁₈ reversed-phase Silica gel (40–63 μm, Merck, Darmstadt, Germany), and Sephadex LH-20 gel (Pharmacia Fine Chemical Co. Ltd., Uppsala, Sweden) were used in the chromatography processes. Fractions were monitored by TLC, and spots were detected on heated TLC plates (Silica gel GF₂₅₄ plates, Qingdao Marine Chemical Inc., Qingdao, China) with 10% H₂SO₄ in EtOH under UV light.

Optical rotations were measured on an MCP-500 spectropolarimeter (Anton Paar, Graz, Austria). UV spectra and ECD spectra were acquired on a UV-2600 spectrophotometer (Shimadzu, Kyoto, Japan). IR spectra were obtained on an Affinity-1 spectrometer (Shimadzu, Kyoto, Japan) using KBr discs. NMR spectra were recorded on a Bruker Avance-500 spectrometer (Bruker, Fällanden, Switzerland) using residual solvent signals as references. HRESIMS data were acquired by the Thermo MAT95XP spectrometer (Thermo Fisher Scientific, Bremen, Germany). Silica gel (80–100, 100–200, and 200–300 mesh, Qingdao Puke Parting Materials Co., Ltd., Qingdao, China) used for flash column chromatography was purchased commercially. The TLC analysis was carried out using commercially available silica gel plates (Qingdao Puke Parting Materials Co., Ltd., Qingdao, China). A Hitachi Primaide (Hitachi Instruments (Dalian) Co., Ltd., Dalian, China) equipped with a diode array detector (DAD) using a preparative YMC ODS C18 column (20 mm × 250 mm, 5 μm) was used for semipreparative HPLC separation. All solvents were analytical grade and used without further purification (Guangzhou Chemical Regents Company, Ltd., Guangzhou, China).