C 18 rp silica gel

Optical rotation was measured with a Jasco P2000 polarimeter (Jasco Corporation, Tokyo, Japan), and FT-IR spectra using a Jasco FT/IR-4200 (Jasco corporation, Japan). ECD and UV spectra were recorded with an Applied Photophysics Chirascan-plus CD spectrometer. ¹H, ¹³C and 2D NMR spectra were obtained on a Varian 400 (Varian, Palo Alto, CA, USA)-400MHz. Waters Xevo G2 Q-TOF, (Waters, Milford, MA, USA) spectra were measured on a Q-TOF mass spectrometer. Semi-preparative high-performance liquid chromatography (HPLC) was performed on a Gilson 321 pump, Gilson 172 Diode Array Detector (Gilson, Middleton, WI, USA). YMC-pack Ph, 250 × 20 mm (YMC, Tokyo, Japan) and Luna 5u C18 column 250 × 10 nm (Phenomenex) as HPLC columns were used. MPLC was run on Isolera One (Biotage, Cardiff, UK). Solvents for HPLC were acetonitrile (MeCN) (HPLC grade) and methanol (HPLC grade), purchased from SK Chemical (Seoul, Korea). Water was purified using a MIlli-Q system (Millipore, Bedford, MA, USA). Column chromatography was performed on C-18 RP silica gel (Cosmosil, Kyoto, Japan) and Sephadex LH-20 (GE Healthcare, Stockholm, Sweden). TLC analysis was run on silica gel 60 F₂₅₄ plates (Marck, Darmstadt, Germany). The spots were visualized by spraying with 10% aqueous H₂SO₄.

Nuclear magnetic resonance (NMR) spectra were obtained using a Varian 400 spectrometer (Varian, Palo Alto, CA, USA) 400 MHz spectrometer operated at 400 MHz for ¹H-NMR and at 100 MHz for ¹³C-NMR. High-resolution mass spectra data were measured on a Xevo G2 Q-TOF mass spectrometer (Waters, Milford, MA, USA). Fourier Transform Infrared (FT-IR) recorded on a Nicolet™ iS™ 5 FT-IR spectrometer (ThermoFisher Scientific, Madison, WI, USA) were used. Ultraviolet visible spectroscopy was performed using a DU 730 UV/Vis spectrophotometer (Beckman Coulter GmbH, North Rhine-Westphalia, Germany). Optical rotation and CD data are also given in the Supplementary file. Semi-preparative high performance liquid chromatography (HPLC) was performed on a system equipped with a Gilson 321 pump and Gilson 172 Diode Array Detector (Gilson, Madison, WI, USA) using YMC-pack Ph (250 × 20 mm) and YMC-pack Ph (250 × 10 mm) HPLC columns (YMC, Kyoto, Japan). Water was purified using a Milli-Q system (Waters Corporation, Milford, MA, USA). Column chromatography on C-18 RP silica gel (Cosmosil, Kyoto, Japan) and Sephadex LH-20 (GE Healthcare, Uppsala, Sweden) was conducted, and TLC analysis on silica gel 60 F₂₅₄ plates (Merck, Darmstadt, Germany) was done. The spots were visualized by spraying with 10% aqueous H₂SO₄.