Abstract

The thermodynamics of the inclusion reaction of flavonol, 7-methoxyflavonol and 4-phenyl-7-hydroxycoumarin (L) with /8-cyclodextrin (CD) has been studied fluorometrically with special reference to the effect of organic solvents (S). The equilibrium constants for this reaction were determined in aqueous methanol, ethanol, acetonitrile, acetone, dimethyl sulfoxide, and A’.A-dimethylformamide. The dependence of the constants on the content of the respective S was attributable to the substitution of S included in CD with L as CD ·nS+L ⇌ CD · L+nS. Also, the inclusion constants of S with CD, βn=[CD · nS][CD]-1[S]-n, were found to be linearly correlated with the solubility parameter of S for both n=1 and 2. When aqueous methanol was employed as a mobile phase, the retention behavior of coumarins on a reversed-phase HPLC column was studied in the presence of j8-CD as a mobile-phase component. The change in the capacity factors could be reasonably explained by the same inclusion scheme as that mentioned above.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.