Polyazamacrocycles anionic complexes

Macrocyclic systems—polyazamacrocycles. Anion complexation can only occur when over a certain range of pH the anion exists and the host ligand is in its protonated form. With the macropolycyclic systems previously described, this prerequisite for binding is obeyed for halide and azide guest anions. However, for the important classes of carboxylate and adenosine... 

Polyazamacrocycles (or azacrown ethers) attract a thorough and constant interest of the researchers due to their imique ability of selective complexation of various metals, organic and inorganic anions, and some polar moleeules. During the last decades himdreds of such compounds were synthesized, whieh eontain nitrogen, oxygen, and sulfur atoms [1], Many polyazamacrocycles can serve as molecular sensors due to their photochemical or redox properties, they contain aromatic moieties which can be present as substituents at nitrogen atoms or can be incorporated in the cycle. 

---