Preparative separation of chromones in plant extract of Saposhnikovia divaricata by high‐performance counter‐current chromatography

Abstract Four chromones, prim‐ O ‐glucosylcimifugin, 4′‐ O ‐β‐ D ‐glucosyl‐5‐ O ‐methylvisamminol, cimifugin and sec‐ O ‐glucosylhamaudol, were isolated and purified from Saposhnikovia divaricata for the first time by high‐performance counter‐current chromatography (HPCCC) using a system consisting of ethyl acetate/ n ‐butanol/ethanol/water (1:1:0.1:2, v/v/v/v). The separation parameters were first performed on the analytical HPCCC and the optimized conditions were then scaled up to preparative HPCCC. A total of 72.1 mg of prim‐ O ‐glucosylcimifugin, 27 mg of 4′‐ O ‐β‐ D ‐glucosyl‐5‐ O ‐methylvisamminol, 14.1 mg of cimifugin and 1.1 mg of sec‐ O ‐glucosylhamaudol were purified from 960 mg of the n ‐butanol extract of S. divaricata , each at over 90% purity as determined by high‐performance liquid chromatography (HPLC). The structures of four compounds were identified by their retention time, the liquid chromatography‐electrospray ionization‐mass spectrometry (LC‐ESI‐MS) in the positive ion mode, and confirmed by NMR. The characteristic LC‐ESI‐MS fragmentation patterns of the four compounds were discussed, and found to be a very specific and useful tool for the structural identification of chromones from S. divaricata .