Agilent 6530 q tof lc ms system

LC-MS analysis was conducted on an Agilent HPLC 1260 Infinity II coupled with an Agilent 6530 Q-TOF-LC-MS system (Agilent Technologies, Palo Alto, CA, USA). The HPLC column was a reversed-phase ZORBAX RRHT Extend-C₁₈, 2.1 by 50 mm, 1.8 μm (Agilent Technologies, USA). The mobile phase was a gradient of 0.1% formic acid in water (A) and acetonitrile (B) at a flow rate of 0.2 mL/min. A linear gradient was initiated with 2% acetonitrile and linearly increased to 95% at 5.1 to 10 min. The flow rate was 0.2 mL/min, and the injection volume was 5 μL. Mass spectra in the m/z range 111 to 3,000 were obtained by positive ion (positive electrospray ionization) modes. The mass spectrometry conditions were the following: gas temperature, 300°C; N2 flow rate, 7 liters/min; nebulizer gas pressure, 35 lb/in²; capillary voltage, 3,500 V; fragmentor potentials, 175 V; Vcap, 3,500 V; skimmer, 65 V; and octopole RFPeak, 750 V. Data acquisition and analysis were conducted using Agilent LC-MS-QTOF MassHunter Data Acquisition Software version 10.1 and Agilent MassHunter Qualitative Analysis Software version 10.0, respectively (Agilent Technologies, USA).

Preparative HPLC was performed on a Gilson HPLC system (Middleton, WI, USA) which consisted of a binary pump, a liquid handler, a UV/Vis detector and a Luna C18(2) column (21.2 × 250 mm I.D., 5 μm, phenomenex, Torrance, CA, USA). Silica gel 60 (40–63 μm, Merck, Germany) and ZEOprep 90 C18 (40–63 μm, Zeochme, Uetikon, Switzerland) were used for column chromatography. The semi-preparative scale high-performance countercurrent chromatography (HPCCC) instrument used was a Spectrum instrument (Dynamic Extractions, Berkshire, UK). The HPCCC system was composed of an IOTA 300 s pump (ECOM, Prague, Czech Republic), a Sapphire 600 UV–VIS detector (ECOM, Prague, Czech Republic) and a Foxy R2 fraction collector (Teledyne Isco, Lincoln, NE, USA). LC–MS data were obtained using an Agilent 6530 Q-TOF LC/MS system (Agilent Technologies, Santa Clara, CA, USA). One-dimensional (1D) and two-dimensional (2D) NMR data were recorded on an Avance 500 spectrometer (Bruker, Karlsruhe, Germany). Organic solvents were purchased from Dae-Jung Chemical Co., Ltd. (Seoul, Republic of Korea).