Agilent 500 mhz

¹H-NMR spectra were recorded on an Agilent 500 MHz (NMR, Agilent Technology, Santa Clara, CA, USA) at a frequency of 500 MHz at room temperature with an acquisition time of 0.011.

Optical rotations were measured on a Jasco P-1020 digital polarimeter (Jasco, Tokyo, Japan). The UV spectra were recorded on a Beckman DU640 spectrophotometer (Beckman Ltd., Shanghai, China). The CD spectra were obtained on a Jasco J-810 spectropolarimeter (Jasco, Tokyo, Japan). The NMR spectra were measured by Agilent 500 MHz (Agilent, Beijing, China), JEOL JNMECP 600 spectrometers (JEOL, Beijing, China). The 7.26 ppm and 77.16 ppm resonances of CDCl₃ were used as internal references for the ¹H and ¹³C NMR spectra, respectively. The 7.16 ppm and 128.06 ppm resonances of C₆D₆ were used as internal references for the ¹H and ¹³C NMR spectra, respectively. The HRESIMS spectra were measured on Micromass Q-Tof Ultima GLOBAL GAA076LC mass spectrometers (Autospec-Ultima-TOF, Waters, Shanghai, China). Semi-preparative HPLC was performed using a Waters 1525 pump (Waters, Singapore) equipped with a 2998 photodiode array detector and a YMC C18 column (YMC, 10 × 250 mm, 5 μm). Silica gel (200–300 mesh, 300–400 mesh, and silica gel H, Qingdao Marine Chemical Factory, Qingdao, China) was used for column chromatography.

Optical rotations were measured using a Jasco P-1020 digital polarimeter (Jasco, Tokyo, Japan). The UV spectra were recorded using a Beckman DU640 spectrophotometer (Beckman Ltd., Shanghai, China). The CD spectra were obtained using a Jasco J-810 spectropolarimeter (Jasco, Tokyo, Japan). The NMR spectra were measured using Agilent 500 MHz (Agilent, Beijing, China) and JEOL JNMECP 600 spectrometers (JEOL, Beijing, China). The 7.26 ppm and 77.16 ppm resonances of CDCl₃ were used as internal references for the ¹H and ¹³C NMR spectra, respectively. The HRESIMS spectra were measured using Micromass Q-Tof Ultima GLOBAL GAA076LC mass spectrometers (Autospec-Ultima-TOF, Waters, Shanghai, China). Semi-preparative HPLC was performed using a Waters 1525 pump (Waters, Singapore) equipped with a 2998 photodiode array detector and a YMC C18 column (YMC, 10 × 250 mm, 5 μm). Silica gel (200–300 mesh, 300–400 mesh, and silica gel H, Qingdao Marine Chemical Factory, Qingdao, China) was used for column chromatography.