1H NMR studies on the hydrogen-bonding network in mono-altro-beta-cyclodextrin and its complex with adamantane-1-carboxylic acid.
The hydrogen-bond network in mono-altro-beta-cyclodextrin and in its inclusion complex with adamantane-1-carboxylic acid were investigated by (1)H NMR spectroscopy using the chemical shifts, temperature coefficients and vicinal coupling constants of the exchangeable hydroxy protons. The chemical shifts of the 3-OH signals indicated that the hydrogen-bond network between the 2-OH and 3-OH groups was disturbed not only on each side of the altrose residue, but also along the whole dextrin chain. Upon addition of adamantane-1-carboxylic acid, altrose underwent a conformational change from the (1)C(4) to the (O)S(2) form, allowing a more continuous belt of hydrogen bonding, as evidenced by the downfield shift experienced by the 3-OH proton signals of the glucose residues.
Hakkarainen
Birgit
B
Department of Chemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Fujita
Kahee
K
Immel
Stefan
S
Kenne
Lennart
L
Sandström
Corine
C
D000218:Adamantane / Q000031:analogs & derivatives* / Q000737:chemistry; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D011522:Protons; D047392:beta-Cyclodextrins / Q000737:chemistry*
D011522:Protons; D047392:beta-Cyclodextrins; C012698:adamantanecarboxylic acid; D000218:Adamantane