6230 lc tof mass spectrometer

Optical rotation values were determined using a JASCO P-1020 polarimeter. UV spectra were recorded using a Hitachi U-2900 spectrometer. ECD spectra were acquired with a JASCO J-820 spectropolarimeter and IR spectra were recorded using a Shimadzu FTIR-8400S spectrophotometer. NMR spectra were acquired with a JEOL JNM-ECZ 400S spectrometer with tetramethylsilane as an internal standard. ESI–MS data were obtained using an Agilent 6230 LC/TOF mass spectrometer. HPLC was performed on a Hitachi HPLC system equipped with an L-2130 pump, an L-2200 autosampler, an L-2300 column oven, and an L-2455 diode array detector. Silica gel AP-300 (Toyota Kako), Sephadex LH-20 (GE Healthcare), and Cosmosil 75C₁₈-OPN (Nacalai Tesque) were used for column chromatography (CC). Silica gel 60 F₂₅₄ and RP-18 F_254S (Merck) were used for TLC analysis.

UV-vis spectra were recorded on a U-2900 spectrophotometer (HITACHI High-Technologies Co., Ltd, Tokyo, Japan). Absorption measurements over the spectral range of 250 nm to 450 nm were carried out in quartz cells having an optical path length of 1 cm. ¹H NMR and ¹³C NMR spectra were recorded on a JEOL ECZ-400S spectrometer (JEOL Ltd, Tokyo, Japan). The solvent used for NMR measurements was CDCl₃. ESI mass spectra were measured on an Agilent Technologies 6230 LC/TOF mass spectrometer (Agilent Technologies Japan, Ltd, Tokyo, Japan).