Synthesis of Novel 4-((Substituted bis-indolyl)methyl)-benzo-15-crown-5 for the Colorimetric Detection of Hg2+ Ions in an Aqueous Medium

The Synthesis of 2,2-BIS(1-INDOL-3-YL)Acenaphthylene-1(2)-Ones Using Nanocatalysis: Fluorescent Sensing for Cu2+ Ions

2,2-bis(1H-indol-3-yl)acenaphthylene-1(2H)-ones were synthesised by the reaction of acenaphthenequinone and 2 equivalents of indole using Fe3O4@SiO2@Si-Pr-NH-CH2CH2NH2 as the basic magnetic nanocatalyst, assembled under greener and sustainable conditions in high purity and yields. Furthermore, the photoluminescence properties of 2,2-bis(2-methyl-1H-indol-3-yl)acenaphthylene-1(2H)-one were exploited for the sensing of copper ions in the mixed solvent systems comprising H2O and CH3CN in excitation wavelength at 410 nm with a detection limit of 9.5 ∙ 10–6 M.

Heterocyclic Crown Ethers with Potential Biological and Pharmacological Properties: From Synthesis to Applications

Cyclic organic compounds with several ether linkages in their structure are of much concern in our daily life applications. Crown ethers (CEs) are generally heterocyclic and extremely versatile compounds exhibiting higher binding affinity. In recent years, due to their unique structure, crown ethers are widely used in drug delivery, solvent extraction, cosmetics manufacturing, material studies, catalysis, separation, and organic synthesis. Beyond their conventional place in chemistry, this review article summarizes the synthesis, biological, and potential pharmacological activities of CEs. We have emphasized the prospects of CEs as anticancer, anti-inflammatory, antibacterial, and antifungal agents and have explored their amyloid genesis inhibitory activity, electrochemical, and potential metric sensing properties. The central feature of these compounds is their ability to form selective and stable complexes with various organic and inorganic cations. Therefore, CEs can be used in gas chromatography as the stationary phase and are also valuable for cation chromatographic to determine and separate alkali and alkaline-earth cations.

Novel integrated sensing system of calixarene and rhodamine molecules for selective colorimetric and fluorometric detection of Hg2+ ions in living cells

Three novel and facile calixarene derivatives (5, 6 and 7), which were appended with four rhodamine units at the upper rim of calixarene skeleton, were firstly prepared and evaluated for selective detection of metal ions in solution. Receptors (5) and (7) indicated immediate turn on fluorescence output toward Hg²⁺ ions over other most competitive metal ions with the ultralow detection limits, indicating their high efficiency and reliability. The binding response to Hg²⁺ ions in solution was also observed through a chromogenic change (from colorless to pale pink). Furthermore, in vitro and bio-imaging studies with MCF-7 or MIA PaCa-2 cell lines were also performed to investigate the use of receptors in biological systems in order to monitor of mercury ions. Results showed that new receptors (5) or (7) were cell permeable and suitable for real-time imaging of Hg²⁺ in living cells (MCF-7) or (MIA PaCa-2) without any damage to healthy cell lines (HEK 293).