Calix[4]arene containing thiourea and coumarin functionality as highly selective fluorescent and colorimetric chemosensor for fluoride ion

Anion Binding by Fluorescent Ureido-Hexahomotrioxacalix[3]arene Receptors: An NMR, Absorption and Emission Spectroscopic Study

“…Different fluorophores like naphthalene, anthracene and pyrene are among the most incorporated in the calixarene framework, leading to fluorescent probes for the recognition of different types of analytes. Examples of fluorescent calix[4]arene [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 ], calix[5]arene [ 14 ] and calix[6]arene [ 15 , 16 ] receptors have been reported in the literature.…”

Fluorescent Lower Rim 1,3-Dibenzooxadiazole Conjugate of Calix[4]arene in Selective Sensing of Fluoride in Solution and in Biological Cells Using Confocal Microscopy

“…From the fluorescence titration data, the lowest detection limit for F – by L was obtained, 109 ppb (100 nM) (Figure SI04a), and this value is lower than that reported in the literature based on calixarene derivatives. ,,− The lowest detection limit is derived based on 3σ/ m , where σ corresponds to the standard deviation of the blank measurements, and m is the slope obtained from the plot of intensity versus sample concentration. The Stern–Volmer quenching constant ( K SV ) for L by F – is (4.2 ± 0.23) × 10 3 M –1 , confirming a high sensitivity of L toward F – .…”

“…In this regard, the calix[4]­arenes are important owing to their (i) amphiphilic nature, (ii) presence of arene core, (iii) presence of the platform suitable for organic derivatization both at lower and upper rims, and (iv) presence of flexible arms to provide suitable and selective coordination environment. Their demonstrated success in the areas of chemo-sensors, catalysis, biomimetic models, and supramolecular science provides an added advantage to calix[4]­arene based molecular systems. − There are only a few receptor molecules based on the calixarene platform in the literature for the detection of fluoride ions in solution, − though there is no report to our knowledge where fluoride ions are being detected both in solution and in biological cells using a calixarene conjugate.…”

Fluorescent cyclophanes and their applications

“…58 They are usually prepared by covalent conjugation of fluorophores (Fig. 8a–i) such as anthracenes, 59 pyrenes, 60 BODIPYs, 61 phenanthridines, 62 coumarins, 63 anthraquinones, 64 dansyls, 65 naphthalenes, 66 fluoresceins, 67 naphthalimides, 68 perylene diimides 69 (PDI), or porphyrins, 70 as side chains ( 21–29 ). Among calix[ n ]arenes, the calix[4]arene scaffold has been widely investigated as a result of its facile synthesis and ease of derivatization compared to calix[6]- and calix[8]arenes.…”