Polyamide-Scorpion Cyclam Lexitropsins Selectively Bind AT-Rich DNA Independently of the Nature of the Coordinated Metal

Abstract

Cyclam was attached to 1-, 2- and 3-pyrrole lexitropsins for the first time through a synthetically facile copper-catalyzed “click” reaction. The corresponding copper and zinc complexes were synthesized and characterized. The ligand and its complexes bound AT-rich DNA selectively over GC-rich DNA, and the thermodynamic profile of the binding was evaluated by isothermal titration calorimetry. The metal, encapsulated in a scorpion azamacrocyclic complex, did not affect the binding, which was dominated by the organic tail.

Molecular Switches for any pH: A Systematic Study of the Versatile Coordination Behaviour of Cyclam Scorpionands

“…Ligands 1 and 5 – 13 were all converted into the respective copper(II) and nickel(II) complexes by reaction with the metal perchlorate salt using procedures adapted from those reported previously for related systems …”

“…[37,55] Ligands 1 and 5-13 were all convertedi nto the respective copper(II) and nickel(II) complexes by reaction with the metal perchlorate salt using procedures adapted from those reported previously for relateds ystems. [37,[55][56][57] Coordination properties in the solid state Thirteen X-ray crystal structures were obtaineda nd this set is augmented furtherw ith structures previously reported for the copper complexes of the triazole ligands [Cu (12)](ClO 4 ) 2 and Scheme1.Synthesis of scorpionands bearinga na minoethyl pendant. a) Previous route to 1 through aziridine opening.…”

A direct method for the N-tetraalkylation of azamacrocycles

“…We sought a simple route to cyclam and cyclen derivatives N -tetraalkylated with propargyl (CH 2 C≡CH) and aromatic groups, as part of ongoing efforts to develop multi-functionalised cyclam derivatives for fluorescence sensing [25–28 40–41] and other biomedical applications [14–16 42–43]. However, we found the previously reported methods to be at best capricious when it comes to substitution with propargyl groups, and the other larger, hydrophobic moieties in which we are interested, leading primarily to over-alkylation and the formation of quaternary amine salts.…”

Cyclam-Based Polymeric Copper Chelators for Gene Delivery and Potential PET Imaging

“…The sharp peak at the equivalent point indicates the formation of a well-defined uniform cyclam−metal complex. 31 The addition of excess Cu(II) gives absorbance above 600 nm, which corresponds to the unbound CuCl 2 . All three RPC polymers (Figure 2C−E) showed absorption maximum at λ max = 570 nm that reached maximum absorbance at a nearly equimolar cyclam/Cu ratio, indicating that cyclam units in the RPC are sterically accessible to Cu(II) complexation.…”