A route to virtually unlimited functionalization of water-soluble p-sulfonatocalix[4]arenes

Nanofluidic Device for Detection of Lysine Methylpeptides and Sensing of Lysine Methylation

Protein methylation is the smallest possible yet vitally important post-translational modification (PTM). This small and chemically inert addition in proteins makes the analysis of methylation more challenging, thus calling for an efficient tool for the sake of recognition and detection. Herein, we present a nanofluidic electric sensing device based on a functionalized nanochannel that was constructed by introducing monotriazole-containing p-sulfonatocalix[4]arene (TSC) into a single asymmetric polymeric nanochannel via click chemistry. The device can selectively detect lysine methylpeptides with subpicomole sensitivity, distinguish between different lysine methylation states, and monitor the lysine methylation process by methyltransferase at the peptide level in real time. The introduced TSC molecule, with its confined asymmetric configuration, presents the remarkable ability to selectively bind to lysine methylpeptides, which, coupled with the release of the complexed Cu ions, allows the device to transform the molecular-level recognition to the discernible change in ionic current of the nanofluidic electric device, thus enabling detection. This work could serve as a stepping stone to the development of a new methyltransferase assay and the chemical that specifically targets lysine methylation in PTM proteomics.

Triazolated calix[4]semitubes: assembling strategies towards long multicalixarene architectures

Cone and 1,3-alternate calix[4]arenes bearing pairs of 2-azidoethyl or propargyl groups, and 1,3-alternate calix[4]arenes having four 2-azidoethyl, four propargyl groups or pairs of 2-azidoethyl and silylated propargyl groups were explored...

Inherently dinuclear iridium(III) meso architectures accessed by cyclometalation of calix[4]arene-based bis(aryltriazoles)

Conventional cyclometalation of calix[4]arene bis(aryltriazoles) with iridium(III) chloride hydrate leads to unique meso architectures in which the Ir₂Cl₂ core is cross-bound by two (C^N)₂ ligands, which allows further replacement of the chloride bridges with ancillary ligands while maintaining the dinuclear structures of the complexes having independent or coupled iridium pairs.

Investigation of supramolecular interaction of quercetin with N,N-dimethylamine-functionalized p-sulfonated calix[4,8]arenes using molecular modeling and their in vitro cytotoxic response towards selected cancer cells

Although quercetin is an effective bioactive compound preventing the progress of several human cancers, its impact is reduced due to low bioavailability.

Assembling triazolated calix[4]semitubes by means of copper(i)-catalyzed azide–alkyne cycloaddition

Calix[4]arene-based bis(alkynes) and bis(azides) react with each other under thoroughly tuned CuAAC conditions and produce diverse biscalixarene semitube assemblies linked by two triazole units, which are capable of binding transition metal cations.

Selective azide–alkyne cycloaddition reactions of azidoalkylated calixarenes

Reaction of calixarene oligo(azides) with alkynes taken in deficiency lead selectively to oligo(triazoles) under Cu(i) catalysis. Same azides react with alkynes intramolecularly under copper-free conditions forming 1,5-substituted triazole bridges.