A Modular Phosphorylated Glycoluril-Derived Molecular Tweezer for Potent Binding of Aliphatic Diamines
A molecular tweezer based on a glycoluril-derived framework bearing four phosphate groups was synthesized and shown to be capable of binding organic amines in aqueous solution. This work reports the Ka values for 30 complexes of this molecular tweezer and amine guests, determined by means of 1H NMR titrations. Both the hydrophobic cavity and the phosphate groups contribute to the binding. Bulkier molecules and molecules bearing negatively charged groups like carboxylates in amino acids bind less tightly due to a steric clash and coulombic repulsion. The narrow cavity and the strong ionic interactions of the phosphate groups with ammonium guests favor binding of aliphatic diamines. These binding properties clearly distinguish this system from structurally related molecular clips and tweezers.
Heilmann, Michael,Tiefenbacher, Konrad
supporting information
p. 12900 - 12904
(2019/11/05)
Chiral Receptors for Lysine Based on Covalently Linked Bis- and Tris-binaphthylphosphoric Acids
The synthesis and application of three chiral receptors based on the covalent linkage of 1,1′-binaphthylphosphoric acids is reported. The binding of the lysine enantiomers to the chiral receptors was investigated by DOSY-NMR and NMR titrations, revealing that the bisphosphoric acid 1d acts as a highly stereoselective receptor for binding of d-lysine.
Hydration of amino acids from ultrasonic measurements
In this paper the results of compressibility of aqueous solutions of amino acids in water and in aqueous HCl and NaOH solutions at 25 °C are presented. The effect of the charged protonated amino groups and deprotonated carboxylic groups on the hydration number was tested. The idea of additivity of the hydration number with the constituents of the solute molecule was successfully applied and discussed.
Burakowski, Andrzej,Gliński, Jacek
experimental part
p. 12157 - 12161
(2011/01/11)
CATALYTIC ASYMMETRIC SYNTHESIS OF L-LYSINE
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Klabunovskii, E. I.,Karpeiskaya, E. I.,Levitina, E. S.,Godunova, L. F.,Kaigorodova, L. N.