Separation of Isomeric Compounds by High Speed Countercurrent Chromatography
高速逆流色谱分离同分异构体

High speed countercurrent chromatography (HSCCC) was successfully used for the separation and preparation of isomeric compounds. The influence of various two-phase solvent systems on the resolution of the natural catechin isomers of (-) -epigallocatechin gallate (EGCG) and (-) -gallocatechin gallate (GCG) from green tea polyphenols and the synthetic isomeric compounds of para-, ortho-, meta-bromoanilline was investigated. The results indicated that the catechin isomers of (-) -EGCG and (-) -GCG can be isolated through two runs of preparative HSCCC with two-phase solvent system composed of n-hexane-ethyl acetate-water (1: 10: 10 in volume ratio). The upper organic phase was used as stationary phase and the lower aqueous phase as mobile phase, while the mobile phase was operated at a flow rate of 3.5 mL/min, and the apparatus rotated at 800 r/min. High performance liquid chromatographic analysis of (-) -EGCG and (-) -GCG revealed that the purity was all over 98%. The isomeric compounds of para-, ortho-, meta-bromoaniline can also be effectively isolated through a single run of preparative HSCCC with the mobile phase flow rate of 3.0 mL/min and the apparatus rotation speed of 800 r/min by using tetrachloromethane-chloroform-methanol-water (7: 3: 7: 3 in volume ratio) as two-phase solvent system, while the lower phase was selected as stationary phase and the upper phase as mobile phase.