HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY COUPLED TO NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPY - APPLICATION TO THE ECDYSTEROIDS OF SILENE OTITES

High-performance liquid chromatography (HPLC) coupled to nuclear magne tic resonance (NMR) spectroscopy has been used to obtain H-1 NMR spect ra of ecdysteroids present in an extract of the plant Silene otites. R eversed-phase gradient chromatography was performed using a (H2O)-H-2- acetonitrile-trifluoroacetic acid-based solvent system. Diagnostic NMR spectra were obtained for 20-hydroxyecdysone, 2-deoxy-20-hydroxyecdys one and 2-deoxyecdysone using the stopped-flow HPLC-NMR technique. The compounds were present in the extracts in amounts between ca. 12 and 135 mu g on-column (as determined using HPLC-UV). (C) 1998 Elsevier Sc ience B.V.