The behaviour of two cyclen-based bismacrocycles linked by aromatic spacers as receptors of adenosine monophosphate (AMP), adenosine diphosphate (ADP) and adenosine triphosphate (ATP) anions is explored. The two bismacrocycles differ from one another by the nature of their spacers, which are respectively 1,3-dimethylbenzene (BMC), or 2,6-dimethylpyridine (BPyC). Potentiometric investigations supported by (1)H and (31)P NMR measurements were performed over a wide pH range to characterize and understand the driving forces implicated in the supramolecular assemblies. A comparison is also carried out with the results presented in this work and those obtained previously with these two ligands and inorganic phosphates. The comparison exhibits the importance of pi-stacking capability of the organic anions in the binding and hydrogen-bonding network. For BPyC, NMR studies highlight two coordination schemes depending on the protonation of the nitrogen atom of the pyridinyl spacer, which acts in acidic media as a supplementary anchoring point.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/b719514a | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Cyclen-based bismacrocycles for biological anion recognition. A potentiometric and NMR study of AMP, ADP and ATP nucleotide complexation.
Org Biomol Chem
May 2008
UMR CNRS 6521, Chimie, Electrochimie Moléculaire et Analytique, Université de Bretagne Occidentale, C. S. 93837, 6 avenue Victor Le Gorgeu, 29238, Brest, Cedex 3, France.
The behaviour of two cyclen-based bismacrocycles linked by aromatic spacers as receptors of adenosine monophosphate (AMP), adenosine diphosphate (ADP) and adenosine triphosphate (ATP) anions is explored. The two bismacrocycles differ from one another by the nature of their spacers, which are respectively 1,3-dimethylbenzene (BMC), or 2,6-dimethylpyridine (BPyC). Potentiometric investigations supported by (1)H and (31)P NMR measurements were performed over a wide pH range to characterize and understand the driving forces implicated in the supramolecular assemblies.
View Article and Find Full Text PDFSynthesis and characterisation of bis-cyclen based dinuclear lanthanide complexes.
Org Biomol Chem
April 2006
School of Chemistry, Centre for Synthesis and Chemical Biology, Trinity College Dublin, Dublin 2, Ireland.
The design and synthesis of several bis-macrocyclic cyclen (1,4,7,10-tetraazacyclododecane) ligands and their corresponding lanthanum or europium complexes is described; these dinuclear lanthanide systems were made by connecting two macrocyclic cyclen moieties through a rigid, covalent, p-xylylenediamide bridge or a flexible aliphatic hexane bridge. These ligands were subsequently functionalised with six acetamide pendant arms (CONR1R2: R1 = R2 = H or CH3, or R1 = H, R2 = CH3). The corresponding lanthanide bis-complexes were then formed by reaction with La(III) and Eu(III) triflates, yielding overall cationic (+VI charged) complexes.
View Article and Find Full Text PDFCyclen based bis-macrocyclic ligands as phosphates receptors. A potentiometric and NMR study.
Dalton Trans
September 2005
UMR CNRS 6521, Chimie, Electrochimie Moléculaire et Analytique, Université de Bretagne Occidentale, C. S. 93837, 6 avenue Victor Le Gorgeu, 29238 Brest Cedex 3, France.
The host-guest interaction between orthophosphate, pyrophosphate and triphosphate anions and four cyclen based bis-macrocycles ligands possessing ortho-(BOC), meta-(BMC), para-xylenyl (BPC) or 2,6-pyridinyl (BPyC) linker was investigated by potentiometric measurements and NMR spectroscopy. Each ligand gave protonated species in aqueous solution that further formed ternary complexes after binding with anions; these complexes were analyzed as a result of hydrogen bond formation and Coulombic attraction between the organic host and the inorganic guest. The equilibrium constants for all the detected species are reported and the selectivity, illustrated with species distribution diagrams, is discussed.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!