C of the complexes of furosemide with 2-hydroxypropyl-b- cyclodextrin and sulfobutyl ether-7-b-cyclodextrin

The purpose of this study was to prepare and characterize complexes of furosemide with 2-hydroxypropyl-b-cyclodextrin (2-HP-b-CD) and sulfobutyl ether-7-b-cyclodextrin (SBE-7-b-CD). Solid complexes of furosemide with 2-HP-b-CD and SBE-7-b-CD were prepared by using both a freeze-drying and kneading method. Physical mixtures were prepared for comparison. The inclusion complexes were 1 characterized by differential scanning calorimetry, X-ray diffractometry (XRD) and H nuclear magnetic resonance spectroscopy 11 ( H-NMR). H-NMR, and especially the use of the two-dimensional ROESY spectrum, was used to determine the position of the 1 furosemide molecule inside the cyclodextrin cavity. H-NMR studies showed that furosemide fit into the cyclodextrin torus cavity with its furane ring nearest to the primary hydroxyl side.  2002 Elsevier Science B.V. All rights reserved.