3230-42-0Relevant academic research and scientific papers
Microwave assisted synthesis of 4-aminophenol Schiff bases: DFT computations, QSAR/Drug-likeness proprieties and antibacterial screening
Abdelakder, Hellal,Abdellah, Benhamou,Mohamed, Mersellem
, (2021/07/21)
The present work is devoted to the synthesis and study of the structural and electronic properties of three Schiff bases prepared from para-aminophenol under green chemistry conditions. These compounds were successfully synthesized in excellent yields. The synthesized Schiff bases have been characterized by Elemental analysis, FTIR, and NMR (1H and 13C) spectroscopic methods. The molecular geometry, Mulliken atomic charges and vibrational analysis of the studied compounds were investigated theoretically by performing density functional theory (DFT) using the B3LYP/6-31G++(d,p) method. Moreover, these compounds were screened for antibacterial activity. These compounds were found active to be the most active against all the bacteria investigated. The antibacterial activities have been correlated with chemical reactivity parameters and other electronic parameters looking for any relationship between electronic parameters and biological activity. This effort just provides preliminary data for some biological properties. The results are very encouraging, so we can say that these products are biologically active and can be used later in other applications towards drug development.
Additional effect of para-hydroxyl on the reduction potentials of the N-benzylidenebenzenamines
Cao, Chao-Tun,Zhou, Wei,Cao, Chenzhong
, (2019/12/27)
The reduction potential ERed of disubstituted N-benzylidenebenzenamines XArCH NArY (abbreviated as XBAY) is a measure of the electron acceptance ability of the Lowest-energy Unoccupied Molecular Orbital (LUMO) in molecule, which is closely related to the electronic effects of substituents X and Y in molecule. Previous studies on the ERed of XBAY reported by Luo, Wang, and Yuan all did not involve these molecules containing hydroxyl. In this work, 28 samples of disubstituted N-benzylidenebenzenamines containing para-hydroxyl, (abbreviated as 4-OHBAY or XBAOH-4′) were synthesized, and their ERed values were measured. Then, 127 compounds were taken as a complicated ERed data set, which involved 28 compounds (4-OHBAY and XBAOH-4′) of this work and 99 compounds XBAY reported by Luo. Based on these data ERed set, through a quantitative regression analysis method and comparison of the factors affecting the ERed, the following results are obtained: (a) Because the phenolic hydroxyl OH can dissociate H+ to form phenolic oxygen anion, the change regularity of ERed of compounds 4-OHBAY and XBAOH-4′ is somewhat different from that of ERed of XBAY compounds without hydroxyl OH. That is, hydroxyl OH has an additional effect on the ERed, which decreases the ERed value. (b) The additional effects of 4-OH on the ERed is different from that of 4′-OH. The effect of hydroxyl OH attached to the aldehyde aromatic ring on the ERed is more than that of OH attached to the amine aromatic ring.
Abnormal effect of hydroxyl on the longest wavelength maximum in ultraviolet absorption spectra for bis-aryl Schiff bases
Cao, Chao-Tun,Zhou, Wei,Cao, Chenzhong
, (2017/09/19)
Two sets of bis-aryl Schiff bases that contain 4(or 4′)-OH and 2(or 2′)-OH were synthesized. The first set consists of 4-HOArCH=NArY and XArCH=NArOH-4′, and the second set consists of 2-HOArCH=NArY and XArCH=NArOH-2′. Their ultraviolet absorption spectra were measured and investigated. A very interesting phenomenon was observed by analyzing their wave number νmax (cm?1) of longest wavelength maximum λmax (nm) of ultraviolet. Compared with the change regularity of the νmax of XArCH=NArY (where the X and Y excluded OH), the 4′-position hydroxyl (4′-OH) and 2′-position hydroxyl (2′-OH) have abnormal performance. The details are the following: the 4′-OH contributes an additional red shift to the νmax of XArCH=NArOH-4′ (λmax increase), whereas the 2′-OH contributes an additional blue shift to the νmax of XArCH=NArOH-2′ (λmax decrease). In addition, there are ortho steric effects of all 2-OH and 2′-OH on the νmax for 2-HOArCH=NArY and XArCH=NArOH-2′, and the ortho steric effect contributes a red shift to their νmax. These experimental facts can provide an important theoretical reference for us using aryl Schiff base compounds as optical materials and performing the molecular design.
Spectrometric and kinetics studies involving anionic chromogenic chemodosimeters based on silylated imines in acetonitrile or acetonitrile-water mixtures
Nicoleti, Celso R.,Nandi, Leandro G.,Ciancaleoni, Gianluca,Machado, Vanderlei G.
, p. 101853 - 101861 (2016/11/11)
Three chromogenic anionic chemodosimeters (1-3) based on silylated imines were synthesized and characterized. Solutions of compound 1 in acetonitrile with 4.0% (v/v) of water are colorless, but with the addition of several anions only CN-, and
A simple protocol for the visual discrimination of natural cyclodextrins in aqueous solution using perichromic probes
Nandi, Leandro G.,Nicoleti, Celso R.,Stock, Rafaela I.,Barboza, Tainá A.,Andreaus, Jürgen,Machado, Vanderlei G.
, p. 1600 - 1606 (2015/02/19)
(Graph Presented) Three synthesized compounds, 4-(4-nitrostyryl)phenol, 2,6-dibromo-4-(2,4-dinitrobenzylideneamino) phenol and 2,6-dichloro-4-(2,4-dinitrobenzylideneamino)phenol, were deprotonated to generate the perichromic dyes 2b, 3b and 4b, respectively. These dyes were used as probes to investigate the micropolarity of natural cyclodextrins (CyDs) and it was observed that they interact differently with the CyDs according to the molecular structure of the dye and the diameter of the CyD. The solvatochromic bands of the dyes that interacted with the CyDs were bathochromically shifted, suggesting that the probes were transferred to the hydrophobic interior of the CyD in aqueous solution. Dyes 2b and 4b were found to be very selective for α-CyD and γ-CyD, respectively, while β- and γ-CyD changed the color of the solution of compound 3b. These dyes were then successfully used in a simple assay that allows the naked-eye discrimination of natural CyDs in aqueous solution, without the need for expensive techniques.
Versatile synthesis of 4-spiro-β-lactam-3-carbonitriles via the intramolecular nucleophilic cyclization of N-(p-hydroxyphenyl)cyanoacetamides
Abdellaoui, Hassane,Xu, Jiaxi
, p. 4323 - 4330 (2014/06/10)
A series of 4-spiro-cyclohexadienonyl-β-lactam-3-carbonitriles, 2,7-dioxo-1-azaspiro[3.5]nona-5,8-diene-3-carbonitriles, was synthesized in satisfactory to excellent yields via the intramolecular nucleophilic cyclization of N-(p-hydroxyphenyl)cyanoacetamides with iodobenzene diacetate (IBD) as oxidant and potassium hydroxide as base. Acetic 4-spiro-cyclohexadienonyl- β-lactam-3-carbimidic anhydrides were obtained when organic base triethylamine was applied instead of potassium hydroxide. The mechanisms of the intramolecular nucleophilic cyclization and formation of acetic β-lactam-3-carbimidic anhydrides were proposed. The cyclization is a sequence of nucleophilic ipso addition and oxidative dearomatization. The formation of acetic carbimidic anhydrides is an acid-catalyzed acetate addition to the nitriles.
Anionic chromogenic chemosensors highly selective for fluoride or cyanide based on 4-(4-Nitrobenzylideneamine)phenol
Nicoleti, Celso R.,Marini, Vanderleia G.,Zimmermann, Lizandra M.,MacHado, Vanderlei G.
, p. 1488 - 1500,13 (2020/08/24)
4-(4-Nitrobenzylideneamine)phenol was used in two strategies allowing the highly selective detection of F- and CN-. Firstly, the compound in acetonitrile acts as a chromogenic chemosensor based on the idea that more basic anions cause its deprotonation (c
Design, synthesis, biological evaluation, and comparative Cox1 and Cox2 docking of p-substituted benzylidenamino phenyl esters of ibuprofenic and mefenamic acids
Hegazy, Gehan H.,Ali, Hamed I.
experimental part, p. 1259 - 1270 (2012/03/27)
Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently associated with gastric mucosal and renal adverse reactions, related to inhibition of cyclooxygenase1 (Cox1) in tissues where prostaglandins exert physiological effects. This led us to develop a set of ibuprofenic acid and mefenamic acid esters, namely: 4-((4-substituted benzylidene)amino)phenyl 2-(4-isobutylphenyl) propanoate and 4-((4-substituted benzylidene)amino)phenyl 2-((2,4- dimethylphenyl)amino)benzoate analogs, which were synthesized by condensation of the corresponding acids with Schiff's bases [4-(4-substituted benzylideneamino)phenols] involving dicyclohexyl carbodiimmide (DCC) as mild dehydrating agent. The main objective is to reduce the GIT toxicity associated with acute and chronic NSAIDs use. Anti-inflammatory, analgesic as well as ulcerogenic activities of the prepared esters were evaluated in vivo and compared with that of ibuprofen as reference standard in all screenings, involving the carrageenan induced paw oedema model and hot plate method. Most of the synthesized esters showed remarkable analgesic and anti-inflammatory activities. Interestingly, all of the compounds were found to be non-ulcerogenic under the tested conditions. This evidence have suggested that modification of the carboxyl function of representative NSAIDs results in retained or enhanced anti-inflammatory and analgesic activities with reduced ulcerogenic potential. Additionally, a comparative AutoDock study into Cox 1 and Cox2 has been done involving both of rigid and flexible docking for potential selectivity of our compounds within different Cox enzymes and to find out the binding orientation of these novel esters into their binding site. Some of the newly prepared aforementioned compounds showed considerable more Cox2 over Cox1 binding affinities by flexible docking better than rigid one.
Nitro-substituted 4-[(phenylmethylene)imino]phenolates: Solvatochromism and their use as solvatochromic switches and as probes for the investigation of preferential solvation in solvent mixtures
Nandi, Leandro G.,Facin, Felipe,Marini, Vanderléia G.,Zimmermann, Lizandra M.,Giusti, Luciano A.,Silva, Robson Da,Caramori, Giovanni F.,MacHado, Vanderlei G.
, p. 10668 - 10679 (2013/02/22)
Four 4-[[(4-nitrophenyl)methylene]imino]phenols (2aa-d) were synthesized. After deprotonation in solution, they formed the solvatochromic phenolates 3aa-d, which revealed a reversal in solvatochromism. Their UVa-vis spectroscopic behavior was explained on
Syntheses, crystal structures and photophysical measurements of phosphite-substituted schiff base and azobenzene liagands
Murphy-Jolly, Makeba B.,Owens Jr., Samuel B.,Freeman, Jason L.,Gray, Gary M.,Lawson, Christopher M.,Shelton, David P.
experimental part, p. 5263 - 5271 (2011/03/01)
Organic chromophores with charge asymmetry may exhibit significant second-order nonlinear optical (NLO) properties. Metal complexes have been used as the donor, the acceptor, or as the bridge in some of these chromophores. Metal complexes may also be usef
