Study on the Inclusion Compounds of Eugenol with alpha-,beta-,gamma-and Heptakis(2,6-di-OMICRON-methyl)-beta-cyclodextrins

摘要

Several host-guest inclusion compounds of eugenol as a guest molecule and cyclodextrins(alpha-,beta-,gamma-CD)and heptakis(2,6-di-OMICRON-methyl)-beta-cyclodextrin(DMbeta-CD)as hosts were investigated in the solid state and in aqueous solution.The one-to-one solid inclusion compounds of eugenol and beta-CD or gamma-CD were prepared,but those of eugenol with alpha-or DMbeta-CD were not obtained under the same condition.However,the UV-visible absorption spectroscopy data indicated that the liquid guest could form a 1:1 inclusion compound with all four hosts respectively in aqueous solution.The two solid inclusion compounds were characterized by powder X-ray diffraction(XRD),infrared spectroscopy(IR),thermogravimetric analysis(TG),differential scanning calorimetry(DSC)and nuclear magnetic resonance(NMR).The association constants(K),calculated from the modified Benesi-Hidebrand equation,of eugenol with alpha-,beta-,gamma-and DMbeta-CD is 4.95 X 10~4,3.96 X 10~5,1.47 X 10~5 and 9.33 X 10~4 mol~(-1)dm~3,respectively.