1128-67-2Relevant articles and documents
Tuneable Redox Chemistry and Electrochromism of Persistent Symmetric and Asymmetric Azine Radical Cations
Werr, Marco,Kaifer, Elisabeth,Wadepohl, Hubert,Himmel, Hans-J?rg
, p. 12981 - 12990 (2019)
Molecular organic radicals have been intensively studied in the last decades, due to their interesting optical, magnetic and redox properties. Here we report the synthesis and characterisation of persistent organic radicals from one-electron oxidation of redox-active azines (RAAs), composed of two guanidinyl or related groups. By connecting two different groups together, asymmetric compounds result. In this way a series of compounds with varying redox potential is obtained that could be oxidised reversibly to the mono- and the dicationic charge states. The accessible redox states were fully determined by chemical redox reactions. The standard Gibbs free energy change for disproportionation of the radical monocation into the dication and the neutral molecule in solution, estimated from cyclovoltammetric measurements, varies between 43 and 71 kJ mol?1. While the neutral RAAs absorb predominately UV light, the radical monocations display strong absorptions covering almost the entire visible region and extending for some compounds into the NIR region. A detailed analysis of this highly reversible electrochromism is presented, and the fast switching characteristics are demonstrated in an electrochromic test device.
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Riemschneider
, p. 683 (1958)
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A cationic bright yellow 7 GL preparation method
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, (2018/05/07)
The invention relates to a preparation method of cation bright yellow 7GL. The method comprises the following steps: (1) synthetizing 3-ethyl thiazole truxene hydrazone: A) methylation: taking 2-aminobenzothiazole, dichloroethane and a catalyst I, stirring and mashing the aminobenzothiazole, the dichloroethane and the catalyst I, adding dimethyl sulphate to the mixture at 30-35 DEG C, wherein the total adding time is 60-100 minutes, then, carrying out heating till the temperature is 60-70 DEG C, carrying out reaction for 1-2 hours to the end, adding water, carrying out heating for temperature rise and recovering dichloroethane, recovering to 90 DEG C, finishing the recovery of the dichloroethane so as to obtain a water solution containing an intermediate as shown in the formula 1; B contracting and mixing: in a solution of the intermediate as shown in in the formula 1, firstly adding the catalyst II, regulating the pH to be 2-4, then adding hydrazine hydrate to reach 98-99 DEG C, carrying out reaction for 4-5 hours, after reaction, lowering the temperature, performing filtration so as to obtain the 3-ethyl thiazole truxene hydrazone containing an intermediate as shown in the formula 2; (2) synthetizing 2-chlorine methyl imidazole truxene; (3) synthetizing a dye. The preparation method disclosed by the invention is high in yield, low in expense, environment-friendly and zero in pollution.
Design, synthesis and biological evaluation of novel unsymmetrical azines as quorum sensing inhibitors
Chourasiya, Sumit S.,Kathuria, Deepika,Singh, Shaminder,Sonawane, Vijay C.,Chakraborti, Asit K.,Bharatam, Prasad V.
, p. 80027 - 80038 (2015/10/05)
Targeting quorum sensing signals using quorum sensing inhibitors has opened new avenues for the application of known antibiotics. In this context, twenty five unsymmetrical azines were synthesised and evaluated as quorum sensing inhibitors. An efficient one-pot procedure was adopted that directly links 3-methyl-2-(methylthio)benzo[d]thiazol-3-ium salt, hydrazine hydrate and substituted aldehyde to give the designed compounds. The synthesized compounds were preliminarily tested for their potential to inhibit CviR receptor based QS signals in Chromobacterium violaceum. The bioassay screening results suggested that two compounds exhibited potent QS inhibition activity against CviR receptor, showing violacein inhibition (>50%) at 200 μM. Further, the putative positive hits were checked for their potential to inhibit LasR receptor-based QS using the PlasB-gfp(ASV) biomonitor strain of Pseudomonas aeruginosa. These compounds were found to inhibit the QS-mediated GFP signals in a dose dependant manner. Two active compounds also exhibited biofilm clearance at 50 μM concentration. Docking studies were performed to examine their potential to bind to the LasR protein of Pseudomonas aeruginosa.
