New Methods for Preparing Cyclodextrin Inclusion Compounds: III: Preparation of Heptakis-(2,6-di-O-methvlV/J-cvclodextrin-Benzoic Acid Inclusion Compound by Sealed Heating

Abstract

The inclusion compound of heptakis-(2,6-di-0-methyl)-/l-cyclodextrin (DM ft CD) and benzoic acid was prepared by heating in a sealed container. Inclusion formation was studied as a function of heating temperature, heating time, mixing molar ratio, and crystallinity of DM/I CD measured by X-ray diffractometry and infrared spectrometry. The combining molar ratio of benzoic acid to DM/1 CD increased with an increase in heating temperature and time. When amorphous DM/1 CD was used for the inclusion formation, the combining molar ratio of benzoic acid to DMp CD increased to about double the amount of crystalline DM/1 CD used. It was found that the heating temperature, heating time, mixing molar ratio, and crystallinity of DMfi CD affected the formation of inclusion compound. © 1990, The Pharmaceutical Society of Japan. All rights reserved.