Correlation diagrams of stereoisograms for characterizing stereoisomers of cyclobutane derivatives

摘要

Correlation diagrams of stereoisomers are developed as a versatile device for discussing the stereoisomerism of cyclobutane derivatives. A cyclobutane skeleton belongs to an RS-stereoisomeric group, which is constructed by starting from the point group D _4h in order to represent a global symmetry. Stereoisomers derived from the cyclobutane skeleton are treated by a main correlation diagram of stereoisograms under the action of the RS-stereoisomeric group. In order to discuss the local symmetry of each RS-stereogenic center, on the other hand, a promolecule is generated at each RS-stereogenic center, where the RS-stereoisomeric group for specifying the promolecule is constructed by starting from the point group T _d . Such promolecules derived from respective stereoisomers are correlated to each other by using stereoisograms, which are further correlated to give a correlation diagram of stereoisograms. RS-stereodescriptors are discussed on the basis of such correlation diagrams of stereoisograms. Keywords Cyclobutane - Stereochemistry - RS-diastereomeric - RS-stereoisomeric - Stereoisogram - Correlation diagram - RS-stereodescriptors - Global symmetry - Local symmetry