Recognition of AMP, ADP and ATP through Cooperative Binding by Cu(II) and Zn(II) Complexes Containing Urea and/or Phenylboronic—Acid Moieties

Abstract

We report a series of Cu(II) and Zn(II) complexes with different ligands containing a dipicolyl unit functionalized with urea groups that may contain or not a phenylboronic acid function. These complexes were designed for the recognition of phosphorylated anions through coordination to the metal ion reinforced by hydrogen bonds involving the anion and NH groups of urea. The complexes were isolated and several adducts with pyrophosphate were characterized using X-ray diffraction measurements. Coordination of one of the urea nitrogen atoms to the metal ion promoted the hydrolysis of the ligands containing 1,3-diphenylurea units, while ligands bearing 1-ethyl-3-phenylurea groups did not hydrolyze significantly at room temperature. Spectrophotometric titrations, combined with 1H and 31P NMR studies, were used in investigating the binding of phosphate, pyrophosphate (PPi), and nucleoside 5′-polyphosphates (AMP, ADP, ATP, CMP, and UMP). The association constants determined in aqueous solution (pH 7.0, 0.1 M MOPS) point to a stronger association with PPi, ADP, and ATP as compared with the anions containing a single phosphate unit. The [CuL4]2+ complex shows important selectivity for pyrophosphate (PPi) over ADP and ATP.

Tuning the coordination properties of chiral pseudopeptide bis(2-picolyl)amine and iminodiacetamide ligands in Zn(ii) and Cu(ii) complexes

“…In the majority of N-coordinated structures, the amide group is deprotonated, 35,36 while a few examples of structures with coordinated amide NH groups had the fragment as part of an urea group. 37 Coordination via the amide nitrogen atom is also favored when the amide group is in the form of the imidic acid tautomer, 38 or when an additional donor, in many cases a pyridine or quinoline group, further envelopes the metal ion. 39,40 Changes in the amide group coordination mode of bpa ligands containing side chains have been utilized in highly selective Zn(II) and Cd(II) sensors 38,41 and molecular devices.…”

Platinum(II)-Based Host–Guest Coordination-Driven Supramolecular Co-Assembly Assisted by Pt···Pt and π–π Stacking Interactions: A Dual-Selective Luminescence Sensor for Cations and Anions

“…Since the pioneering work on the purely organic polyamine-containing anthracene-based fluorescent probe for the detection of pyrophosphate (PPi, usually in sodium salt; Na 4 P 2 O 7 ) reported by Czarnik and co-workers in 1994, there has been an exponential growth in interest in the development of different kinds of binding motifs for the detection of the biologically important phosphate anions. − In particular, the detection of PPi, as a byproduct of ATP hydrolysis, is an important research area because of its involvement in many essential metabolic reactions, for example, DNA replication catalyzed by the DNA polymerase. − Dipicolylamine-zinc (DPA-Zn) units represent an important class of artificial PPi receptors, first demonstrated by Hamachi and co-workers in 2001 . Inspired by their work as well as the intriguing structural studies of the DPA-Zn-PPi binding reported by other groups, − we believe that the platinum­(II) complexes, possessing the advantage of the propensity to exhibit directional Pt···Pt interactions, would benefit from this well-defined binding mode not only for constructing a new type of supramolecular coordination complex but also for endowing it with the potential application of highly sensitive and selective PPi sensing.…”

Suzuki-Miyaura Coupling Enabled by Aryl to Vinyl 1,4-Palladium Migration

“…The ortho-vinyl arylbromides (1a-1e, 1g-1v, 1B) (Wei et al, 2019;Wei et al, 2018;Ryutaro Hayashi, 2018;Shen et al, 2017;Rossi et al, 2001), (hetero)aryl boronate esters (2a-2h, 2l-2o, 2q, 5a-5c, 5j, 5r) (Zhang et al, 2018;Carreira-Barral et al, 2018;Zhou et al, 2017;Ranjani and Nagarajan, 2017;Bello and Schmidt-Leithoff, 2012;Yu et al, 2010;Gómez-Blanco et al, 2009;Iwai et al, 2008;Stephen J. Baker, 2006;Burstein et al, 2005;Wong et al, 2002), diaryl-vinyl boronate esters (7h, 7i) were prepared according to the literatures. Heteroaryl boronate esters (5g-5h, 5m-5q) and vinyl boronate esters (7a-7g) were purchased and used directly from commercial sources.…”