English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

In supramolecular chemistry, the topic of anion recognition has attracted much attention because of their application in medical, environmental process, chemistry, and biology. Among the various anions, the recognition of oxoanions such as phosphate, sulfate, nitrate, and carbonate and spherical halide anions is an important target due to their important role in organisms, metabolic and environmental processes. In particular, the C3v-symmetric anionic receptors have shown good binding affinity for such oxoanions and halide anions. Recently, we have reported that C3v-symmetric anionic receptors 1a and 1b containing three urea or thiourea moieties on upper arms of trindane framework showed moderate binding affinities toward H2PO4 − in DMSO-d6; 392 and 305 M, respectively. The weakened binding affinity to anions was apparently due to hydrogen-bond breaking and unstable conformation changes in the process of anion recognition. The rigid planar arylarylurea moieties intramolecularly hydrogen bonded between adjacent urea groups in free receptors 1 need to be rotated and oriented toward the anion nested in the center of molecular cavity. To solve the matter of the rigidity of arylarylurea moieties, a much flexible anion receptor 2 was designed, which have three benzylphenylurea binding unit linked to upper arms of C3v-trindane scaffold as shown in Figure 1. We expect that these benzylphenylurea units could induce a stabilization of complex with anion and consequently the binding affinity of receptor 2 could be enhanced. The tripodal receptor 2 was synthesized according to Scheme 1. Tricarboxylic ester-scaffold 3 was treated with chloro(methoxy)methane and SnCl4 to afford tris(chloromethylbenzyl)-scaffold 4 that was converted into tris(azidobenzyl)-scaffold 5 by reaction with NaN3. The azide moieties of this scaffold 5 was hydrogenated in the presence of Ni(W2) catalyst to obtain the corresponding triaminoscaffold 6. Subsequently, reaction of scaffold 6 with commercially available phenyl isocyanate afforded the urea receptor 2 in good yield. The structure of receptor 2 was confirmed by H NMR, C NMR, Maldi-TOF mass, and elemental analysis.

bulletin of the korean chemical society

New Tripodal Anion Receptor Based on C3v-trindane Scaffold with Benzylphenylurea Motifs for Selective H2PO4-Sensing