Aryleneethynylene Trimers Bearing Calix[4]arenes: Synthesis, Optical Properties and Self‐Assembling Studies

Abstract

Summary: New homoditopic bis-calix [4]arene-carbazole conjugates, armed with hydrophilic carboxylic acid functions at their lower rims, are disclosed. Evidence for their self-association in solution was gathered from solvatochromic and thermochromic studies, as well as from gel-permeation chromatography analysis. Their ability to function as highly sensitive sensors toward polar electron-deficient aromatic compounds is demonstrated.

Fostering protein–calixarene interactions: from molecular recognition to sensing

“…Materials CCC-1, 13 CCC-2 13 and CCC-3 14 were synthesized according to our reported procedures and fully characterized by FT-IR, 1 H/ 13 C NMR, and microanalysis. Cytochrome c from equine heart ($95% (SDS-PAGE), Aldrich C2506), myoglobin from equine heart ($90% (SDS-PAGE), Aldrich M1882), lysozyme from chicken egg white ($90%, Aldrich L6876) were purchased from Sigma-Aldrich Corp., EUA, and used as received.…”

“…1), both armed with hydrophilic carboxylic acid functions at their lower rims but differing on the type of substitution at the carbazole rings. 13 It was demonstrated that these uorophores are able to function as highly sensitive sensors toward electron-decient aromatic compounds (picric acid and 2,4,6-trinitrotoluene) used in explosives' compositions in solution as well as serve as structural motifs in the construction of supramolecular polymers in organic solution phase. 13 These new synthetic receptors were also designed having in mind their potential as biosensors.…”

“…13 It was demonstrated that these uorophores are able to function as highly sensitive sensors toward electron-decient aromatic compounds (picric acid and 2,4,6-trinitrotoluene) used in explosives' compositions in solution as well as serve as structural motifs in the construction of supramolecular polymers in organic solution phase. 13 These new synthetic receptors were also designed having in mind their potential as biosensors. 13 Given the spatial distribution and multitude of the potential binding sites provided by the calixarene hosts bearing carboxylic/carboxylate functions and the integrated uorescence transduction element incorporating the bis-carbazolederived aryleneethynylene central unit with good electron donor ability, 14 we thought that strong interactions might be developed with H-bond receptors and cationic guests residing in target proteins (particularly those positively charged amino acids distributed near the heme edge region), which synergistically would foster the overall sensing capabilities toward specic heme-containing proteins, allowing for an efficient differentiation between heme and non-heme proteins.…”