Melting points were determined on a YanacoMP-S3 micro
melting point apparatus and are uncorrected. Optical rotations
were measured on a Perkin-Elmer 241 MC polarimeter. The UV
spectra were taken on a HP 8451A diode array spectrophotometer.
IR spectra were recorded on a NEXUS-470 spectrophotometer. 1D
and 2D NMR spectral data were recorded on Brucker ACF-300P or
Brucker ACF-500P spectrometers in CDCl3. Exact masses (HRESIMS)
were measured by a Waters Synapt HDMS system.
Chromatography was performed on silica gel (200–300 mesh).
Samples were purified on an Agilent 1200 HPLC system equipped
with a 250 10 mm, 5 mm YMC-Pack ODS-A column and G1315D
DAD detector.