Siliabond c18 silica gel

Optical rotations were determined with a JASCO P1020 digital polarimeter. IR spectra were taken on a JASCO FT/IR-4100 spectrometer. The NMR spectra were recorded on a Varian 400MR FT-NMR instrument at 400 MHz for ¹H and 100 MHz for ¹³C, and on a Varian Unity INOVA 500 FT-NMR spectrometer at 500 MHz for ¹H and 125 MHz for ¹³C in CDCl₃. LR- and HR-ESIMS were measured with a Bruker APEX II mass spectrometer. Silica gel 60 (230–400 mesh, Merck, Darmstadt, Germany) and SiliaBond C18 silica gel (40–63 µm, 60 Å, 17% carbon loading, SiliCycle, Québec, QC, Canada) were used for column chromatography. Precoated silica gel plates (Kieselgel 60 F254, Merck, Darmstadt, Germany) and precoated silica gel RP-18 plates (Kieselgel 60 F254S, Merck, Darmstadt, Germany) were used for TLC analysis.

Column chromatography was performed in a glass column using Silica gel 60 (40–63 µm, Merck, Darmstadt, Germany) and SiliaBond C18 silica gel (40–63 µm, 60 Å, 17% carbon loading, Silicycle, Quebec, Canada), and the fractions were pooled according to the TLC analysis using precoated silica gel plates (Kieselgel 60 F₂₅₄, 0.25 mm, Merck, Darmstadt, Germany) and silica gel RP-18 plates (Kieselgel 60 F₂₅₄S, Merck, Darmstadt, Germany). UV and IR spectra were recorded on a PerkinElmer Lambda-265 UV-Vis and a PerkinElmer Spectrum Two FT-IR spectrometers (PerkinElmer Inc., Waltham, MA, USA), respectively. Optical rotations were determined at 25 °C with a JASCO P2000 digital polarimeter (JASCO Co., Tokyo, Japan). The NMR spectra, including the 2D NMR experiments, were performed on Bruker Avance-400 and -500 spectrometers (Bruker BioSpin, Rheinstetten, Germany) with chemical shifts reported in ppm referenced to δ_C 77.0/δ_H 7.26 ppm (CDCl₃) and δ_C 135.5/δ_H 7.58 ppm (pyridine-d₅).