ABSTRACT
Benzimidazole-based pyrrole/piperidine analogs (1-26) were synthesized and then screened for their acetylcholinesterase and butyrylcholinesterase activities. All the analogs showed good to moderate cholinesterase activities. Synthesized compounds (1-13) were screened in cholinesterase enzyme inhibition assays and showed AChE activities in the range of IC50 = 19.44 ± 0.60 µM to 36.05 ± 0.4 µM against allanzanthane (IC50 = 16.11 ± 0.33 µM) and galantamine (IC50 = 19.34 ± 0.62 µM) and varied BuChE inhibitory activities, with IC50 values in the range of 21.57 ± 0.61 µM to 39.55 ± 0.03 µM as compared with standard allanzanthane (IC50 = 18.14 ± 0.05 µM) and galantamine (IC50 = 21.45 ± 0.21 µM). Similarly, synthesized compounds (14-26) were also subjected to tests to determine their in vitro AChE inhibitory activities, and the results obtained corroborated that all the compounds showed varied activities in the range of IC50 = 22.07 ± 0.13 to 42.01 ± 0.02 µM as compared to allanzanthane (IC50 = 20.01 ± 0.12 µM) and galantamine (IC50 = 18.05 ± 0.31 µM) and varied BuChE inhibitory activities, with IC50 values in the range of 26.32 ± 0.13 to 47.03 ± 0.15 µM as compared to standard allanzanthane (IC50 = 18.14 ± 0.05 µM) and galantamine (IC50 = 21.45 ± 0.21 µM). Binding interactions of the most potent analogs were confirmed through molecular docking studies. The active analogs 2, 4, 10 and 13 established numerous interactions with the active sites of targeted enzymes, with docking scores of -10.50, -9.3, -7.73 and -7.8 for AChE and -8.97, -8.2, -8.20 and -7.6 for BuChE, respectively.
ABSTRACT
Rapid detection of toxic ions has taken great attention in the last few decades due to its importance in maintaining a greener environment for human beings. The extreme toxicity of cyanide (CN-) ions is a great environmental concern as its continued industrial use generates interest in facile and sensitive methods for CN- ions detection. Since CN- ions act as a ligand in coordination chemistry which rapidly coordinates with suitable metals and forms complexes, this ability was mainly explored in its detection. It also attacks the central metal in coordination compounds and gives a fluorimetric response. Coordination compounds behave as a sensor for the detection of important ions like CN- ions and have gained great attention due to their facile synthesis, multianalyte detection, clear detection and low detection limit. Recently, considerable efforts have been devoted to the detection and quantification of hazardous multianalyte using a single probe. Cu2+ complexes are the main complexes used for CN- ions detection; however, the complexes of many other metals are also used as sensors. Four basic types of interaction have been discussed in coordination compound sensors for CN- detection. The performances of different sensors are compared with one another and the sensors which have the lowest detection limit are highlighted. This review comprises the progress made by coordination compounds as sensors for the detection of CN- ions in the last six years (2015-2021). To the best of our knowledge, there is no review on coordination compounds as a sensor for CN- ions during this period.
ABSTRACT
To maintain a green and sustainable environment for human beings, rapid detection of potentially toxic heavy metals like mercury (Hg(II)) has attracted great attention. Recently, sensors have been designed which can selectively detect Hg(II) over other common available cations and give a naked eye or fluorometric response. In the last two decades, the trend is shifting from bulky organic chemosensors toward nanoparticles due to their rapid response, low cost, eco-friendly and easy synthesis. In this review, promising nanoparticles-based sensors for Hg(II) detection are discussed. The nano-sensors are functionalized with nucleotide or other suitable materials which coordinate with Hg(II) ions and give clear color or fluorescence change. The operational mechanisms are discussed focusing on its four basic types. The nanoparticles-based sensors are even able to detect Hg in three different oxidation states (Hg(II), Hg(I) and Hg(0)). Recently, the trend has been shifted from ordinary nanoparticles to magnetic nanoparticles to simultaneously detect and remove Hg(II) ions from environmental samples. Furthermore, the nano-sensors for Hg(II) are compared with each other and with the reported organic chemosensors.
ABSTRACT
Precisely engineering the decoration of metal nanoparticles on the special surface of semiconductor represents a promising strategy to design efficient metal-semiconductor heterostructured photocatalysts. This study demonstrates a versatile soft-template method to fabricate a novel nonsymmetrical heterostructured Ag/AgI nanoplate, in which only one side surface of the nanoplate is covered with uniform 2D Ag nanoweb. Compared with symmetrical heterostructure, the nonsymmetrical heterostructure may further facilitate the separation of photogenerated electron-hole pairs and shows a greatly enhanced photocatalytic activity. This study may open up a new way to improve the photocatalytic property by synthesizing nonsymmetrical metal-semiconductor composites.
