Mixis tof qii mass spectrometer

Semipreparative HPLC (Agilent Technologies, 1260 Infinity II series) was performed using an ODS column (YMC-pack ODS-A, 10 mm × 250 mm, 5 μm). Column chromatography (CC) was performed over silica gel (200–300 mesh; Qingdao Marine Chemical Group Co., Qingdao, China) and Sephadex LH-20 (Amersham Biosciences Inc., Piscataway, NJ, USA) and octadecylsilyl silica gel (YMC Co., Ltd., Kyoto, Japan; 50 μm), respectively. Spots were detected on TLC (Qingdao Marine Chemical Factory, Qingdao, China) under 254 nm UV light. The NMR spectra were obtained on a Bruker Avance-600 MHz spectrometer (Bruker, Billerica, MA, USA) with tetramethylsilane as an internal standard. HR-ESI-MS spectra were recorded on a Bruker miXis TOF-QII mass spectrometer (Bruker, Billerica, MA, USA). Optical rotations were determined with a Perkin Elmer MPC 500 (Waltham, MA, USA) polarimeter. The UV, IR, and ECD spectra were recorded on a Shimadzu UV-2600 PC spectrometer (Shimadzu, Kyoto, Japan), an IR Affinity-1 spectrometer (Shimadzu, Kyoto, Japan), and a Chirascan circular dichroism spectrometer (Applied Photophysics, Leatherhead Surrey, UK), respectively. The artificial sea salt was a commercial product (Guangzhou Haili Aquarium Technology Company, Guangzhou, China). Cells were disrupted using a high pressure homogenizer NanoGenizer (Genizer LLC, Irvine, CA, USA).

Optical rotations were measured on a PerkinElmer MPC 500 (Waltham) polarimeter. The UV, IR, and CD spectra were recorded on a Shimadzu UV-2600 PC spectrometer (Shimadzu), an IR Affinity-1 spectrometer (Shimadzu), and a Chirascan circular dichroism spectrometer (Applied Photophysics), respectively. NMR spectra were recorded on a Bruker Avance spectrometer (Bruker) operating at 500 and 700 MHz for ¹H NMR and 125 and 175 MHz for ¹³C NMR that used tetramethylsilane as an internal standard. High resolution electrospray ionization mass spectroscopy (HRESIMS) spectra were acquired on a Bruker miXis TOF-QII mass spectrometer (Bruker). Column chromatography was performed over silica gel (200–300 mesh) (Qingdao Marine Chemical Factory). Spots were detected on TLC (Qingdao Marine Chemical Factory) under 254-nm UV light. All solvents employed were analytical grade (Tianjin Fuyu Chemical and Industry Factory). Semipreparative HPLC was performed using an octadecylsilyl (ODS) column (YMC-pack ODS-A, YMC Co., Ltd., 10 mm × 250 mm, 5 μm). Artificial sea salt was a commercial product (Guangzhou Haili Aquarium Technology Company).

Optical rotations were measured with an AntonPaar MCP 200 automatic polarimeter. Ultraviolet (UV) spectra were obtained on a UV-2550 spectrophotometer (Shimadzu Corporation, Tokyo, Japan). IR spectra were recorded on a Bruker Tensor 27 FT-IR spectrometer (film). 1D and 2D-NMR spectra were carried out on a Bruker AM-400 and an Avance-500 spectrometer, δ in ppm rel. to TMS, J in Hz. ESIMS and HRESIMS were measured with a Bruker miXis TOF-QII mass spectrometer (Bruker, Fällanden, Switzerland), respectively. Silica gel (100–200 mesh, 300–400 mesh, Qingdao Marine Chemical Ltd., Qingdao, China), Sephadex LH-20 (GE Healthcare Bio-sciences AB, Uppsala, Sweden), and YMC GEL ODS-A (S-50 μm, 12 nm) (YMC Co., Ltd., Kyoto, Japan) were used for column chromatography. Semipreparative HPLC analyses were performed using an ODS column (YMC-ODS-A, 250 × 20 mm, 5 μm). Circular dichroism (CD) spectra were measured on a Chirascan circular dichroism spectrometer (Applied Photophysics Ltd., Leatherhead, UK). MTT assays were analyzed using a microplate reader (BioTek Synergy H1, BioTek Instruments, Inc., Vermont, USA).