252Cf plasma desorption mass spectrometric study of the inclusion complexes of cyclodextrins with coumarins

Abstract

252 Cf plasma desorption mass spectrometry was used to investigate the formation of complexes of 7-amino-4-methylcoumarins with -and γ-cyclodextrins. The individual substances and their co-ground mixtures were analyzed by plasma desorption ionization. In the negative-ion mass spectra of cyclodextrins highly characteristic fragmentation peaks were detected, and a scheme for the fragmentation pathway is proposed. The inclusion complex of 7-amino-4-methylcoumarin with -cyclodextrin was obtained, and the peak corresponding to the complex was observed in the PDMS spectra. Various modes of inclusion of the coumarins into cyclodextrins, that can result in stable complex formation, are discussed in the light of molecular mechanics calculations. In spite of the possibility in principle of the inclusion of 7-amino-4-methylcoumarin into -cyclodextrin, and of 7-N,N-diethyl-amino-4-methylcoumarin into γ-cyclodextrin, the complexes of these compounds appear to be insufficiently stable and they decomposed under the desorption/ionization conditions.

Supramolecular Peptide/Surface Assembly for Monitoring Proteinase Activity and Cancer Diagnosis

“…These hollow structures, shaped like a truncated cone with a hydrophilic exterior and an apolar cavity, have a diameter of about 6.6 Å. They are able to form inclusion complexes in aqueous solutions with a large variety of molecules, the stability of such complexes depending on the size and hydrophobic character of the guest molecule. , In particular, β - CDs perfectly accommodate coumarin derivatives, − from 1:1 host–guest complex to higher stoichiometry. , We have previously demonstrated that our biscoumarinic MMP substrates interact with β-CD in solution and form only a stable supramolecular complex between diethylaminocoumarin (DAC)/ β-CD with a K a constant of 3236 M –1 . To validate the ability of our biscoumarinic MMP substrates to form a stable supramolecular assembly with our β-CD surfaces, were performed surface acoustic wave (SAW) studies to investigate their interactions.…”