Effect of substitution on halide/hydrated halide binding: a case study of neutral bis-urea receptors

Abstract

The impact of the substituted moiety on the binding nature of the anion with a neutral receptor through non-cooperative interaction.

N,N′-[1,4-Phenylenebis(iminocarbonyl)]bis(L-phenylalanine) tetrahydrofuran disolvate

“…Bis-urea compounds containing a central 1,4-phenylene unit have been shown to be suitable molecules for anion recognition (Stapf et al, 2015;Casula et al, 2016;Manna et al, 2018;Manna & Das, 2019Das et al, 2020). In this context, we introduced compounds combining this scaffold and various amino acids [such as l-valine, l-leucine, l-proline, (R)-3-piperidinecarboxylic acid, l-threonine or even l-phenylalanine], whose amino group is part of the urea moiety, among them the title compound, possessing l-phenylalanine units (Stapf et al, 2015).…”

Anion-Induced Intramolecular Cyclization of Urea-Based Receptors: Entrapment of Cyclic [SO4(H2O)42–]n Cluster and Encapsulation of Anions with Varied Dimensionality

“…Previously, our group has already explored numerous receptors ranging from monopodal to tripodal receptors for both solid- as well as solution-phase anion recognition study − and most of our studies were limited to organic solvent medium only; less exploration was done toward selective anion recognition in aqueous medium. So keeping that in mind, in our continuous endeavor toward anion recognition chemistry, herein, we have designed a set of two unsymmetrical dipodal monourea receptors BPU-1 and BPU-2 having pi -acidic terminal substituents, containing the benzimidazole moiety as a signaling unit as well as a hydrogen donor/acceptor site, to investigate their anion recognition behavior in both solid states as well as in solution phase and also to perform fluorimetric sensing study of both the receptors in the presence of various anions in 100% aqueous medium.…”

Trapped Cyclic Dimeric Oxyanion Assembly by a Urea-Functionalized Receptor: Potent Application in Linear Discriminant Analysis and as Antibacterial Agents

“…In our continuing effort to encapsulate an anion/hydrated anion assembly by urea-based receptors, − herein, we report the naphthalimide-appended urea-functionalized neutral receptors L 1 and L 2 (Scheme ). Introducing nitrophenyl (electron-deficient) and naphthyl (electron-rich) substituents to the core of the urea functionality, we have generated diversity in the electronic properties as well as the hydrophobicity of these receptors.…”