2302-25-2Relevant academic research and scientific papers
Some contribution to W(VI)-peroxo-chemistry: Synthesis, spectroscopic characterization, reactivity and DFT studies
Bhattacharjee, M.,Boruah, S. R.,Chowdhury, S.,Das, N.,Dutta Purkayastha, R. N.
, (2022/01/14)
Synthesis of white microcrystalline oxodiperoxotungstate(VI) complexes, K[WO(O2)2(L)(H2O)]·H2O, (L ?= ?salicylate, 5-chlorosalicylate, 4-hydroxybenzoate) have been achieved from reaction of Na2WO4·2H2O with 30% H2O2 and the respective hetero-ligands at pH Ca. 7–7.5 in aqueous medium. The newly synthesized compounds were comprehensively characterized by elemental analyses, spectral studies, room temperature magnetic moment measurements and mass spectrometric studies. Infrared spectra suggest that, peroxo groups are bonded to the WO+4 center in a triangular bidentate (C2v) fashion and the hetero-ligands benzene-core hydroxycarboxylic acids viz. salicylic acid, 5-chlorosalicylic acid, 4-hydroxybenzoic acid in anoinic form are coordinated in monodentate manner. Compounds are fairly stable in aqueous solution for sufficient period of time. The results of mass spectrometric analysis lend support to the molecular composition of the complexes ascertained on the basis of elemental analyses and spectroscopic studies. Compound potassium(aquo)(5-chlorosalicylato)oxodiperoxotungstate(VI)monohydrate, K[WO(O2)2(5-chlorosalicylate)(H2O)]·H2O, act as an oxidant of bromide ion in aqueous phase bromination of chosen organic substrates to their corresponding bromo organics. Density Functional Theory (TD-DFT) calculations were performed on the synthesized complexes substantiated the experimentally obtained results. The TD-DFT optimized structures are in excellent agreement with the results of elemental analyses, spectral as well as mass spectrometric data.
Synthesis, anti-HIV-1 and antiproliferative evaluation of novel 4-nitroimidazole derivatives combined with 5-hydroxy-4-pyridinone moiety
Shirvani, Pouria,Fassihi, Afshin,Saghaie, Lotfollah,Van Belle, Siska,Debyser, Zeger,Christ, Frauke
, (2019/11/26)
In an effort to synthesize more effective non-nucleoside reverse transcriptase inhibitors (NNRTIs) against the HIV-1 infection, a new series of novel 4-nitroimidazole derivatives combined with 5-hydroxy-4-pyridinone moiety were designed by molecular docking studies, prepared and characterized by spectroscopic techniques. All the synthesized compounds were in vitro evaluated for their inhibitory effect against the HIV-1 replication in the MT-4 cells. Results showed that none of these synthesized compounds displayed any specific anti HIV-1 activity. Surprisingly, these compounds showed high cytotoxicity against MT-4 cells with low selectivity index (50 = 1.3 μM and EC50 = 1.8 μM respectively).
Reductive dehalogenation and dehalogenative sulfonation of phenols and heteroaromatics with sodium sulfite in an aqueous medium
Tomanová, Monika,Jedinák, Luká?,Canka?, Petr
supporting information, p. 2621 - 2628 (2019/06/03)
Prototropic tautomerism was used as a tool for the reductive dehalogenation of (hetero)aryl bromides and iodides, or dehalogenative sulfonation of (hetero)aryl chlorides and fluorides, using sodium sulfite as the sole reagent in an aqueous medium. This protocol does not require a metal or phase transfer catalyst and avoids using organic solvent as the reaction medium. This method is especially suitable for substrates that readily tautomerize (such as 2-or 4-halogenated aminophenols and 4-halogenated resorcinols), for which dehalogenation or sulfonation proceeds under mild reaction conditions (≤60 °C). As sodium sulfite is an inexpensive, safe, and environmentally less hazardous reagent, this method has at least three potential applications: (i) in the deprotection of halogens as protecting groups, using sodium sulfite as a reducing agent; (ii) in the sulfonation of aromatic halides under mild reaction conditions avoiding hazardous and corrosive reagents/solvents; and (iii) in the transformation of toxic halogenated aromatics into less harmful compounds.
Peroxo–tungstate(VI) complexes: syntheses, characterization, reactivity, and DFT studies
Das, Nandita,Chowdhury, Shubhamoy,Purkayastha, Ranendra N. Dutta
, p. 1255 - 1266 (2019/07/04)
Abstract: Three new oxodiperoxo–tungsten(VI) complexes containing benzene core carboxylic acids, viz., benzoic acid, 2-chlorobenzoic acid, and 3-aminobenzoic acid as co-ligands have been synthesized from reaction of Na2WO6H4, 30% H2O2 and the corresponding co-ligands in aqueous medium. The compounds have been comprehensively characterized by elemental analyses, FT-IR, 1H NMR, UV–Vis spectral studies as well as by mass spectrometric and TGA analyses. The infrared spectra suggest occurrence of terminally bonded W=O as well as triangular bidentate peroxo groups (C2v) and monodentate carboxylate group bound to the WO4+ center. The mass spectra of the compounds are in good agreement with proposed molecular formulations. Thermogravimetric analyses indicate the existence of both lattice and coordinated water molecules in the complexes. Density functional theory (DFT) calculations were used to compute the frequencies of relevant vibrational modes, electronic properties and also to investigate structure of the compounds. Compound potassium(aquo)(2-chlorobenzoato)oxodiperoxo–tungstate(VI)dihydrate acts as an oxidant for bromide ion in aqueous phase bromination of chosen organic substrates to their corresponding bromo-organics. Graphical abstract: [Figure not available: see fulltext.]
Preparation method of 4-halogen-1H-imidazole
-
Paragraph 0037, (2017/08/28)
The invention discloses a preparation method of 4-halogen-1H-imidazol. The method comprises the following steps: (1), enabling imidazole and halogen elementary substance which are taken as raw materials to be in reaction at a temperature of 60 to 100 DEG C in an alkaline condition, and filtering after the reaction, so as to obtain a filter cake 4-halogen-1H-imidazol crude product; (2), enabling the 4-halogen-1H-imidazol crude product and a reducing agent to be in reaction, filling and filtering after the reaction, and performing extraction and vacuum concentration on the filter cake, so as to obtain a 4-halogen-1H-imidazol pure product. The method is simple in technology, high in reaction yield, low in cost, and free from pollution and waste liquid discharge.
A deuterated of the IDO inhibitor and its preparation and use (by machine translation)
-
Paragraph 0044; 0052; 0053; 0054, (2017/04/22)
The invention provides a deuterated of the IDO inhibitor and its preparation and use, as shown in formula I provide compound or its crystalline form, a pharmaceutically acceptable salt, hydrate or solvate. The preparation of the compound or its crystalline form, a pharmaceutically acceptable salt, hydrate or solvate, can be regarded as the IDO inhibitor, can be used for the treatment of IDO related diseases, in particular cancer, viral infection, depression, neurodegenerative disease, trauma, age-related cataract, organ transplant rejection and autoimmune diseases. (by machine translation)
Highly regioselective C-5 alkynylation of imidazoles by one-pot sequential bromination and Sonogashira cross coupling
Bellina, Fabio,Lessi, Marco,Marianetti, Giulia,Panattoni, Alessandro
supporting information, p. 3855 - 3857 (2015/06/08)
A variety of 2-substituted 5-alkynyl-1H-imidazoles were easily prepared by a one-pot sequential procedure involving a highly regioselective electrophilic C-5 bromination of 1,2-dimethyl-1H-imidazole, 2-chloro-1-methyl-1H-imidazole, and 2-aryl-1-methyl-1H-imidazoles, followed by an efficient palladium/copper co-catalyzed Sonogashira-type alkynylation.
Rapid kinetics and relative reactivity of some five membered aromatic heterocycles using hydrodynamic voltammetry
Walke,Bonde,Bhadane,Dangat,Jadhav
, p. 2239 - 2245 (2016/02/27)
Kinetics of the bromination of imidazole, pyrazole and thiazole by molecular bromine and N-bromosuccinimide has been studied in aqueous medium. Since the reactions are rapid special technique namely, hydrodyanamic voltammetry has been employed to follow the course of the reactions. These reactions follow second order kinetics. The comparative kinetic data determines the reactivity order for these heterocycles towards the bromination using two different brominating reagents. The study justifies the stereochemical principles ascertaining the relative reactivity of these heterocycles quantitatively using kinetics as an investigational tool.
Fast halogenation of some N-heterocycles by means of N,N'-dihalo-5,5- dimethylhydantoin
Sandtorv, Alexander H.,Bjorsvik, Hans-Rene
, p. 499 - 507 (2013/05/08)
An instantaneous, selective and high-yielding halogenation process is reported. The method operates with imidazoles, pyrazoles, and indoles under benign reaction conditions. The developed process involves the use of N,N'-dihalo-5,5-dimethylhydantoins (halo=chlorine, bromine, iodine) as halogenation reagents that are activated by catalytic quantities of a strong Bronsted acid. Moreover, the halogenation process is switchable to produce either the mono- or di-halogenated products. Issues related to the reaction mechanism are investigated and a proposal for a reaction mechanism is disclosed.
Regioselective, photochemical bromination of aromatic compounds using N-bromosuccinimide
Chhattise, Prakash K.,Ramaswamy,Waghmode, Suresh B.
, p. 189 - 194 (2008/03/30)
Regioselective nuclear bromination of aromatic compounds is investigated with N-bromosuccinimide as the brominating agent under UV irradiation to afford the corresponding brominated compounds. The reaction proceeds at ambient temperature (30 ± 2 °C) without any catalyst. In most of the reactions, regioselectively mono-brominated products are obtained in good to high yields. The conversion and selectivity for bromination depend on the nature of the substituent on the aromatic ring.
