HPLC analysis was carried out with a Dionex UltiMate 3000 system coupled with an UltiMate 3000 pump linked to a photodiode array detector (DAD 3000 RS). Detection wavelengths were set at 235, 254, 280, and 340 nm. The column was prefilled with Eurospher 100-10 C18, 125 × 4 mm (Knauer, Germany). The routine HPLC analysis was performed with the following gradient (MeOH : 0.1% HCOOH in H2O): 0 min (10% MeOH); 5 min (10% MeOH); 35 min (100% MeOH); 45 min (100% MeOH). Semipreparative HPLC was conducted with a Merck Hitachi Chromaster HPLC system (UV detector 5410; pump 5110; column Eurospher 100-10 C18, 300 × 8 mm, Knauer; flow rate at 5 mL min−1). Silica gel 60 M (Macherey-Nagel) was used for vacuum liquid chromatography (VLC) and Sephadex LH-20 for column chromatography. TLC plates pre-coated with silica gel 60 F254 (Macherey-Nagel) were used for routine analysis. One- and two-dimensional NMR spectra were recorded on Bruker AVANCE DMX 600 or 500 NMR spectrometers. ESIMS and HRESIMS data were acquired by a Finnigan LCQ Deca mass spectrometer and an UHR-QTOF maXis 4G (Bruker Daltonics) mass spectrometer, respectively. FT-IR spectra were recorded on a Bruker Tensor 37 IR spectrometer in a range of 4000–400 cm−1 with the resolution of 4 cm−1 as a KBr pellet. Optical rotations were measured on a Jasco P-2000 polarimeter.
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