Title:Chiral Ligand-Exchange Chromatography of Pharmaceutical Compounds on Dynamically Coated (Home-Made) Stationary Phases
Volume: 24
Issue: 8
关键词:
手性色谱法,对映异构体拆分,配体交换,动态涂层,浸渍手性试剂,薄层色谱,高效液相色谱。
摘要: It is well known for several decades that the two enantiomeric forms of a chiral
compound can have very different effects on the human body. For this reason the synthesis
or extraction from a natural source of a potential new drug, as well as its marketing, require
a careful control of its optical purity. Chromatographic techniques can respond extremely
well to this need, both in the analytical and in the preparative field.
Among the several methods developed for this purpose, one of the first and of the most effective
is the Chiral Ligand-Exchange Chromatography, which is based on the stability difference
between the metallic diastereomeric complexes containing one or the other of the
two enantiomers to be separated and a suitable chiral selector. This method has been effectively
used for resolving racemic mixtures of products of biomedical and/or pharmacological
interest, such as α - and β-amino acids either proteinogenic or non-proteinogenic, oligopeptides,
amino alcohols or β-blockers. All these substances are linked together by their
ability to bind metal ions, the most widely used of which is Cu(II). The chiral selector can
be a component of either the mobile or the stationary phase, to which it can be either
chemically bonded or dynamically adsorbed. The latter method has several advantages of
convenience and, above all, cheapness. The preparation of dynamically-coated chiral stationary
phases for Ligand-Exchange Chromatography has produced a large number of applications,
the main of which, both in TLC and in HPLC, are reviewed below.