Spectroscopic Analysis of Organic Compounds

Specific rotations were measured using JASCO P-2000 polarimeter. NMR spectra were obtained from Bruker DRX-400 NMR spectrometer equipped with Cryoprobe. The NMR spectrometer used a 5-mm BBI (¹H, G-COSY, multiplicity-edited G-HSQC, and G-HMBC spectra) or BBO (¹³C spectra) probe heads equipped with z-gradients. Agilent 1260 Infinity Preparative-Scale LC/MS Purification System equipped with Agilent 6130B single quadrupole mass spectrometer detector was used to conduct preparative HPLC analyses. Agilent 5 Prep C₁₈ column (10 mm × 30 mm) was used for HPLC runs. HPLC-MS experiment was performed on an Agilent UHPLC 1290 Infinity coupled with a diode array detector (DAD), and an Agilent 6540 accurate-mass quadrupole time-of-flight (QTOF) mass spectrometer equipped with a splitter and an ESI source. The analyses were conducted with Acquity UPLC BEH C18 column (2.1 mm × 50 mm, 1.7 μm) under standard gradient condition of 98% (0.1% formic acid) to 100% MeCN (0.1% formic acid) over 8.6 min, at a flow rate of 0.5 ml/min. The operating parameters for QTOF were the same as in (Sirota et al., 2018 (link)).