Fluorescence enhancement of coumarin-6-sulfonyl chloride amino acid derivatives in cyclodextrin media.
Coumarin-6-sulfonyl (6-CS) amino acid derivatives form inclusion complexes with a- and /-cyclodextrins (CD) in aqueous solution. The stoichiometry of the inclusion complex and the equilibrium constant were investigated. Using a fluorescence technique and alanine-beta-CD as a model, a 1:2 guest-host complex was established, and K = 4.7 x 10(5) mol(-2) l(2) was obtained. Fluorescence enhancement was observed for all derivatives studied, with glycine exhibiting a greater enhancement, and tyrosine showing the least. The stability of the inclusion complex was found to depend on the respective sizes of the guest-host complex and their interaction.
Al-Kindy
S M
SM
College of Science, Department of Chemistry, Muscat, Sultanate of Oman. alkindy@squ.edu.om
Suliman
F E
FE
Al-Hamadi
A A
AA
D000409:Alanine / Q000031:analogs & derivatives / Q000737:chemistry; D000596:Amino Acids / Q000737:chemistry*; D002942:Circular Dichroism; D003374:Coumarins / Q000737:chemistry*; D003505:Cyclodextrins / Q000737:chemistry*; D015394:Molecular Structure; D012996:Solutions / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods; D047391:alpha-Cyclodextrins; D047392:beta-Cyclodextrins
D000596:Amino Acids; D003374:Coumarins; D003505:Cyclodextrins; D012996:Solutions; D047391:alpha-Cyclodextrins; D047392:beta-Cyclodextrins; C031215:betadex; D000409:Alanine; C032613:alpha-cyclodextrin