Methods for treating some pentacyclic triterpenoids

This article describes the methods of purification the most important representatives of a lupane and olean series (betulin diacetate betulin and allobetulin) by using recrystallization and column chromatography methods, as well as a comparison of methods and it was concluded about the most effective and preferred methods. It was observed, that the purification of technical substances for pentacyclic triterpenoids by recrystallization method is not efficient, because, the content of the main components in the samples with using this method increases by only 2 %, and there are significant losses during purification. It is established that the best result is achieved by purification of these substances by column chromatography using aluminum oxide as a sorbent. In this case, according to the chromatography-mass spectrometric analysis, the fixed increasing in the content of the main substance in the sample by 4-7 %. It is shown, that this method is convenient for the purification of betulin, betuline diacetate and allobetulin from concomitant impurities and makes it possible to obtain their pure substances suitable for further use in organic synthesis, electrochemical, microbiological, spectral and other methods of investigation. The advantages of the proposed method for the chromatographic purification of triterpenoids are: simplicity of execution, rapidity and high purity of the obtained samples. To compare the effectiveness of the methods of purification of substances were used modern physical and chemical methods of analysis. On the basis of the results, the authors proposed a chromatographic purification method as the most effective can be used for the preparation of pure substances to other representatives of pentacyclic triterpenoids lupane and olean series.