Ionic complexation properties of per(3,6-anhydro)cyclodextrin derivatives towards lanthanides.
Using per(3,6-anhydro)cyclodextrin derivatives [per(3,6-anhydro)CD], it was possible to produce new lanthanide chelates by careful choice of the size and functional groups. Heptakis(3,6-anhydro-2-O-methyl)cyclomaltoheptaose fulfils the best criteria for complexation of lanthanide ions. Nuclear magnetic resonance was used to derive the association constants and the stoichiometries of these new complexes. Finally, a three-dimensional structure of these complexes consistent with the NMR data is proposed, to ascertain the position of lanthanide in the cavity of the per(3,6-anhydro)CD. For the present purposes, heptakis(2-O-acetyl-3,6-anhydro)cyclomaltoheptaose, octakis(2-O-acetyl-3,6-anhydro)cyclomaltooctaose, heptakis(3,6-anhydro-2-O-methyl)cyclomaltoheptaose and octakis(3,6-anhydro-2-O-methyl)cyclomaltooctaose have been synthesized and purified.
Baudin
Cécile
C
CEA, DRECAM/SCM, CEA Saclay, F-91191 Gif-sur-Yvette, France. cbaudin@drecam.cea.fr
Tardy
Fabienne
F
Dalbiez
Jean-Pierre
JP
Jankowski
Christophe
C
Fajolles
Christophe
C
Leclair
Gaëtan
G
Amekraz
Badia
B
Perly
Bruno
B
Mauclaire
Laurent
L
D002236:Carbohydrate Conformation; D007477:Ions / Q000737:chemistry; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D047391:alpha-Cyclodextrins / Q000737:chemistry*
D007477:Ions; D028581:Lanthanoid Series Elements; D047391:alpha-Cyclodextrins; C110521:per(3,6-anhydro)-alpha-cyclodextrin