ISSN:
0952-3499
Keywords:
molecular recognition
;
alkaloids
;
cyclophanes
;
enantioselectivity
;
fluorescence
;
conductometry
;
1H NMR
;
Chemistry
;
Biochemistry and Biotechnology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Medicine
Notes:
The binding of 8-anilino-1-naphthalenesulfonate and 15 anions of substituted benzoic, aliphatic dicarboxylic, and N-acetyl-α-amino acids to a macrocyclic alkaloid d-tubocurarine in aqueous solution has been studied by fluorometry, conductometry, and 1H NMR. The binding constants vary from ca. 50 to 3300 M-1 depending on the guest structure, charge and hydrophobicity. The results of fluorescence and NMR studies show that the host-guest complexation of the anions of aromatic acids involves the formation of a salt bridge between the quaternary nitrogen of the alkaloid and the anionic group of the guest as well as hydrophobic/Van der Waals interactions between the guest and host aromatic moieties. The binding of dianions of aliphatic dicarboxylic acids most probably is purely electrostatic. In general, d-tubocurarine possesses binding ability comparable to that of synthetic cyclophanes. It binds enantiospecifically anions of N-acetyl-α-amino acids and discriminates between positional isomers of anions of hydroxy and carboxy substituted benzoic acids.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
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