Phenanthroline-containing macrocycles as multifunctional receptors for nucleotide anions. A thermodynamic and NMR study †

Abstract

The synthesis of the phenanthroline-containing macrocycle 2,6,10,14-tetraaza [15](2,9)cyclo(1,10)phenanthrolinophane (L1) is reported. L1 contains a tetraamine chain connecting the 2,9-positions of a phenanthroline unit. Protonation of L1 has been studied by means of potentiometric and 1 H and 13 C NMR techniques, allowing the determination of the basicity constants and of the stepwise protonation sites. The protonation features of L1 are compared with those of macrocycle 2,5,8,11-tetraaza[12](2,9)cyclophenanthrolinophane (L2), in which the amine groups are linked by ethylenic chains. Considering the [H 4 L1] 4ϩ and the [H 4 L2] 4ϩ species, the acidic protons are located on the aliphatic nitrogens, while phenanthroline is not involved in protonation. Binding of diphosphate, triphosphate, ATP and ADP has been studied by means of potentiometry and 1 H and 31 P NMR. Both L1 and L2 behave as multifunctional receptors for the nucleotide anions at neutral or slight acidic pHs, giving 1 : 1 complexes. Charge-charge and hydrogen bonding interactions take place between the polyphosphate chain of nucleotides and the polyammonium groups of L1 and L2, while the adenine moiety gives charge-dipole interactions with the ammonium groups and π-stacking with the phenanthroline unit of the receptors. The high upfield displacements in the 1 H NMR spectra exhibited by the adenine protons upon complexation by L1 suggest a partial inclusion of nucleotides inside the macrocyclic cavity.

Artificial Receptors for the Recognition of Phosphorylated Molecules

“…The interactions of 97 and 98 with ADP, ATP, pyrophosphate, and triphosphate were studied through potentiometric titrations. 207 In general, 98 was found to bind phosphates more strongly than 97 for a given protonation state, as seen previously for smaller macrocycles. The stability constants with pyrophosphate and triphosphate, however, were much lower than those with ADP and ATP, respectively, with no binding observed between 98 and triphosphate.…”

Modeling and Biological Investigations of an Unusual Behavior of Novel Synthesized Acridine‐Based Polyamine Ligands in the Binding of Double Helix and G‐Quadruplex DNA

“…Similarly, the reaction of 1 with 1,4,7,10-tetratosyl-1,4,7,10-tetraazadecane (4) [35] and 1,5,9,13-tetratosyl-1,5,9,13-tetraazatridecane (5) [36] afforded the respective tosylated macrocycles 6 and 7, which were then deprotected in HBr/CH 3 COOH/phenol, and further isolated as hydrobromide salts (L2 and L3).…”

Progressive morphology development to produce multilayer films and interpenetrating blends by chaotic mixing

“…Ligand L1 was synthesized by reaction of 2,7‐dibromomethylacridine ( 1 in Scheme )34 with the ditosylated amine 1‐methyl‐1,4‐di(4‐toluenesulfonyl)‐1,4‐diazabutane ( 2 ) in the presence of potassium carbonate, followed by removal of the tosyl (Ts) groups in hydrogen bromide/acetic acid in the presence of phenol as an antioxidant. Similarly, the reaction of 1 with 1,4,7,10‐tetratosyl‐1,4,7,10‐tetraazadecane ( 4 )35 and 1,5,9,13‐tetratosyl‐1,5,9,13‐tetraazatridecane ( 5 )36 afforded the respective tosylated macrocycles 6 and 7 , which were then deprotected in HBr/CH 3 COOH/phenol, and further isolated as hydrobromide salts (L2 and L3).…”