Agilent 6230 accurate mass tof ms mass spectrometer

All reagents and solvents were
purchased from Sigma-Aldrich Co. LLC (Merck KGaA, Darmstadt, Germany)
unless indicated otherwise. Water was purified by a Millipore purification
system (Merck KGaA). NMR spectra were recorded on a Jeol ECA-500 (Jeol
Ltd., Tokyo, Japan). Solvent mixtures for chromatography are reported
as volume/volume (v/v) ratios. Reverse phase high performance liquid
chromatography (HPLC) purifications were performed on a CombiFlash
EZ Prep (Teledyne Isco, Inc.) with a RediSep Prep C18 column (20 ×
150 mm²) with Phase A/Phase B gradients [Phase A: H₂O with 0.1% formic acid; Phase B: MeOH with 0.1% formic acid]
at a flow rate of 19 mL/min. The HPLC was equipped with a UV–vis
detector and an evaporative light scattering detector (ELSD). High-resolution
mass (HRMS) analyses were performed by electrospray ionization–time
of flight (ESI-TOF) on an Agilent 6230 Accurate-Mass TOF-MS mass spectrometer.

Solvent mixtures for chromatography are reported as volume/volume (v/v) ratios. HPLC analyses were performed with an Eclipse Plus C8 analytical column with gradients based on Phase A and Phase B (where Phase A: H₂O with 0.1% formic acid; Phase B: MeOH with 0.1% formic acid). For purification purposes, Zorbax SB-C18 semi-preparative column was used with gradients based on Phase A and Phase B gradients (where Phase A: H₂O with 0.1% formic acid; Phase B: MeOH with 0.1% formic acid). Agilent 6230 Accurate-Mass TOFMS mass spectrometer was used to obtain electrospray ionization-time-of-flight (ESI-TOF) mass spectra. A Varian 380-LC detector was used to record ELSD chromatograms.