Separation and purification of intermediates for the preparation of naproxen from synthetic mixtures by countercurrent chromatography

In this work, a continuous high-speed countercurrent chromatography method has been developed on the basis of elution-extrusion mode and this method was successfully applied to the separation of maslinic and oleanolic acid from the extract of olive pulp. In the process of 'elution', the sample solution was continuously loaded into the column and the maslinic acid was steadily eluted out in this step while highly retained oleanlic acid always stayed in the column. In the process of 'extrusion', the oleanlic acid was pushed out of the column with the stationary phase. In this way, we achieved a large sample loading. A total of 120 mL sample solution (about 89.55% of the column volume) which contains 600 mg olive pulp extract was pumped in the apparatus by a constant-flow pump and the maslinic and oleanolic acids were largely separated within 120 min. Both of these two compounds presented high yields and high purities (271.6 mg for maslinic acid with 86.7% and 83.9 mg oleanolic acids with 83.4%).

Section: Introductionmentioning

confidence: 99%

Continuous separation of maslinic and oleanolic acids from olive pulp by high‐speed countercurrent chromatography with elution‐extrusion mode

Huang

Zhang

Pei

et al. 2019

Section: Introductionmentioning

confidence: 99%

“…CCC is a liquid-liquid partition chromatography that has been widely used for preparative separation of active component from natural product [13], synthetic mixture [14], and fermentation broth [15]. However, only very limited numbers F I G U R E 1 Stereochemical structures of acetyltropic acid enantiomer of studies are available, which are about enantioseparations by CCC [16][17][18][19][20].…”

Section: Introductionmentioning

confidence: 99%

Enantioseparation of acetyltropic acid by countercurrent chromatography with sulfobutyl ether‐β‐cyclodextrin as chiral selector

Qiu

Sun

Wang

et al. 2019

Self Cite

Acetyltropic acid is an important synthetic intermediate for preparation of tropane alkaloid derivatives, which can be used as anticholinergic drugs, deliriants, and stimulants. In the present work, acetyltropic acid was successfully enantioseparated by countercurrent chromatography using sulfobutyl ether-β-cyclodextrin as chiral selector. A biphasic solvent system composed of n-butyl acetate/n-hexane/0.1 mol/L citrate buffer at pH = 2.2 containing 0.1 mol/L of sulfobutyl ether-β-cyclodextrin (7:3:10, v/v) was selected, which produced a suitable distribution ratio D S = 1.14, D R = 2.31 and a high enantioseparation factor α = 2.03. Baseline separation was achieved for preparative enantioseparation of 50 mg of racemic acetyltropic acid. A method for chiral analysis of acetyltropic acid by conventional reverse phase liquid chromatography with hydroxylpropyl-β-cyclodextrin as mobile phase additive was established, and formation constants of inclusion complex were determined. It was found that different substituted β-cyclodextrin should be selected for enantioseparation of acetyltropic acid by countercurrent chromatography and reverse phase liquid chromatography. K E Y W O R D Sacetyltropic acid, countercurrent chromatography, cyclodextrins, enantioseparation, liquid chromatography J Sep Sci 2020;43:681-688.

“…Countercurrent chromatography (CCC) is a new mode of liquid‐liquid chromatography , which is based on the difference in distribution coefficients of solutes in two‐phase solvent system to achieve the compounds separation . The solid support‐free liquid stationary phase is the heart of the CCC technique and it has great impact on the separation result .…”

Section: Introductionmentioning

confidence: 99%

A simple gradient equilibrium method for better separation in countercurrent chromatography

Quan

Huang

et al. 2018

The stationary phase retention is one of the most important parameters in countercurrent chromatography. In this work, a simple gradient equilibrium method was developed to further improve the stationary phase retention based on the optimized condition in the traditional equilibrium model. Meanwhile, this novel gradient equilibrium method was used to separate three flavone model compounds and compared with the conventional isocratic equilibrium method to evaluate the separation efficiency. The results show that better resolution or shorter separation time could be achieved with gradient equilibrium compared to isocratic equilibrium. So this novel equilibrium method has enormous potential for obtaining a better separation or saving the separating time in the preparative separation of target compounds.