103-88-8Relevant articles and documents
Scott,Cashell
, p. 2674,2677 (1970)
Synthesis of Flubromazepam Positional Isomers for Forensic Analysis
Allred, B. McKay,France, Stefan,Jones, Lonnie V.,Ligon, Evelyn S.,Nawyn, Jason,Reinhardt, Daniel V.
, (2019)
Designer benzodiazepines have recently appeared in many forensic cases as legal alternatives to federally scheduled drugs such as diazepam (Valium) and alprazolam (Xanax). Though current forensic instrumental techniques are often sufficient for identifying novel psychoactive substances, they may not readily differentiate between potential positional isomers. Additionally, characterization data for positional isomers of known designer benzodiazepines are widely nonexistent. In this study, flubromazepam, a recognized designer benzodiazepine since 2012, was targeted for synthesis and characterization due to its potential for federal scheduling and current legal status within the United States. A practical synthetic method was developed to prepare purified reference materials for each positional isomer of flubromazepam in which the positions of the bromine and fluorine substituents were varied. Possible isomers (9 of the 12) were successfully prepared and used for further analysis.
Use of 1-halo derivatives of the 2,2,6,6-tetramethylpiperidine series as oxidants and halogenating agents
Kashparova,Kagan,Zhukova,Ivakhnenko
, p. 964 - 967 (2004)
1-Halo derivatives of the 2,2,6,6-tetramethylpiperidine series oxidize sterically hindered phenols to form dimers and p-quinones.
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Mills
, (1860)
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Regioselective and high-yielding bromination of aromatic compounds using hexamethylenetetramine-bromine
Heravi, Majid M.,Abdolhosseini, Nafiseh,Oskooie, Hossein A.
, p. 8959 - 8963 (2005)
A regioselective and highly efficient method for bromination of aromatic compounds in the presence of a stoichiometric amount of hexamethylenetetramine- bromine (HMTAB) as an efficient reagent in dichloromethane is reported. The selectivity depends on the temperature and nature of the substituent on the substrate. The reactivity of this reagent was increased by supporting it to silica gel for bromination of less activated compounds.
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Bell,Levinge
, (1935)
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Selectivity enhancement of aromatic halogenation reactions at the micellar interface: Effect of highly ionic media
Samant, Bhupesh S.,Bhagwat, Sunil S.
, p. 1039 - 1044 (2012)
Halogenation (iodination and bromination) of various aromatic compounds has been studied in micellar media in order to observe the effect on regioselectivity and conversion of the reaction. The addition of surfactant causes a change in the chemical shifts of the aromatic proton resonance of phenol which proves the orientation of the aromatic compound on the micellar surface. However, increase in ionic strength of the reaction media affects the selectivity of reaction by disturbing this spatial orientation of the aromatic compound in the micelle. Selectivity towards particular isomers is dependent on the concentration of the surfactant. In bromination of chlorobenzene (deactivated aromatic compound) enhancement in selectivity and conversion towards the para isomer has been observed.
Ammonium persulphate promoted synthesis of polyethylene glycol entrapped potassium tribromide and its application in acylation and bromination of some selective organic compounds
Dey, Rupa Rani,Dhar, Siddhartha Sankar
, p. 866 - 868 (2013)
In this study, a new method of synthesis of polyethylene glycol supported potassium tribromide (PEG KBr3) and its application in acylation and bromination reactions are reported. Ammonium persulphate oxidizes KBr to the corresponding tribromide which is entrapped by polyethylene glycol leading to stable PEG KBr3. The reagent is proved to be highly efficient for the acylation of variety of alcohols and bromination of activated aromatic substrates. The method is a mild, one pot reaction and involves no use of toxic reagents.
4,4-Dibromo-3-methylpyrazol-5-one: New applications for selective monobromination of phenols and oxidation of sulfides to sulfoxides
Mashraqui, Sabir H.,Mudaliar, Chandrashekar D.,Hariharasubrahmanian, Harini
, p. 4865 - 4868 (1997)
Dibromopyrazolone 1, a stable, crystalline solid effects para selective monobromination of phenols and aniline substrates under mild conditions. Selective oxidation of sulfides to sulfoxides can also be accomplished by using 1 in high yields.
A new method for the oxybromination of aromatic compounds with copper(II)bromide and potassium dichromate
Badri, Rashid,Shushizadeh, Mohammad Reza
, p. 533 - 536 (2005)
A new and mild method for oxybromination of aromatic compounds with CuBr2 and K2Cr2O7 in HOAC is reported. Copyright Taylor & Francis Inc.
In(OTf)3-Catalyzed Synthesis of 2,3-Dihydro-1 H-benzo[ e]indoles and 2,3-Dihydrobenzofurans via [3 + 2] Annulation
Liu, Shuxuan,Zang, Yu,Huang, Hai,Sun, Jianwei
, p. 8219 - 8223 (2020)
An In(OTf)3-catalyzed intermolecular [3 + 2] annulation for the synthesis of 2,3-dihydro-1H-benzo[e]indoles and 2,3-dihydrobenzofurans from readily available substrates has been achieved. This approach takes advantage of oxetane and para-quinone methide as important functional units in the key intermediate. β-Naphthylamines and phenols have been demonstrated as excellent reaction partners.
Green synthesis of tetraalkylammonium tribromide using cerium(IV) ammonium nitrate (CAN) as oxidant
Borah, Ruli,Thakur, Ashim Jyoti
, p. 933 - 939 (2007)
Cerium(IV) ammonium nitrate (CAN) mediates oxidation of tetraalkylammonium bromide to tetraalkylammonium tribromide in greener reaction conditions using water as solvent. The procedure is simple, convenient, and environmentally benign for the synthesis of tetraalkylammonium tribromide with great yields. Copyright Taylor & Francis Group, LLC.
Desulfurization of Thioamides into Amides with H2O 2/ZrCl4 Reagent System
Bahrami, Kiumars,Khodaei, Mohammad Mehdi,Tirandaz, Yeganeh
, p. 369 - 371 (2009)
The hydrogen peroxide/zirconium(IV) chloride reagent system has been used as a new and efficient reagent for the deprotection/desulfurization of thioamides to amides. This system is reasonably general and can be applied to the conversion of several thioamides to the corresponding amides. The salient features of this protocol are short reaction times, good chemoselectivity, cleaner reaction profiles, and simple workup that precludes the use of toxic solvents. Georg Thieme Verlag Stuttgart.
An efficient and regioselective oxybromination of aromatic compounds using potassium bromide and oxone
Narender,Srinivasu,Ramakrishna Prasad,Kulkarni,Raghavan
, p. 2313 - 2318 (2002)
A simple, efficient and regioselective method for oxybromination of aromatics is reported. The electrophilic substitution of bromine generated in situ from potassium bromide using oxone as an oxidant for the first time.
Regioselective and efficient bromination of anilides on water using HBr and Selectfluor
Liang, Deqiang,Li, Xiangguang,Wang, Chaowu,Dong, Qishan,Wang, Baoling,Wang, Hai
, p. 5390 - 5394 (2016)
A metal-, additive-, and Br2-free highly regioselective bromination of anilides using HBr and Selectfluor is presented. This reaction proceeded under mild conditions with high efficiency and good functional group tolerance, and water served as the solvent. In general, with substrates bearing no para-substituent, para-mono-bromination occurred exclusively, while ortho-mono-brominated anilides were the only products when para-positions were blocked. The incorporation of a stronger orienting group might result in a reversed regioselectivity, and the reaction was sensitive to steric hindrance.
Regioselective control of aromatic halogenation reactions in carbon nanotube nanoreactors
Miners, Scott A.,Rance, Graham A.,Khlobystov, Andrei N.
, p. 5586 - 5588 (2013)
The use of single-walled carbon nanotubes as effective nanoreactors for preparative chemical reactions has been demonstrated for the first time. Extreme spatial confinement of reactant molecules inside nanotubes has been shown to drastically affect both the regioselectivity and kinetics of aromatic halogenation reactions.
An efficient chemo and regioselective oxidative nuclear bromination of activated aromatic compounds using lithium bromide and ceric ammonium nitrate
Roy, Subhas Chandra,Guin, Chandrani,Rana, Kalyan Kumar,Maiti, Gourhari
, p. 6941 - 6942 (2001)
A mild, efficient and highly chemo- and regioselective method for the bromination of electron rich aromatic molecules has been developed by electrophilic substitution of Br+, which was generated in situ from LiBr using ceric ammonium nitrate as the oxidant. Free aromatic amines remained unaffected under the reaction conditions.
BROMINATION OF AROMATIC MOLECULES WITH POLYMER SUPPORTED REAGENTS
Zajc, Barbara,Zupan, Marko
, p. 7869 - 7878 (1989)
Crosslinked co poly/styrene-4-vinyl(N-hexylpyridinium bromide) was converted with bromine or chlorine to insoluble polymer supported complexes 1 or 2 respectively, and their reactivity studied in reactions with various aromatic molecules.Reagent 1 was found in all cases to be milder than reagent 2 and regiospecifically transformed alkoxy and amino substituted benzenes (3) into 4-bromo derivatives, while corresponding reactions with 2 resulted in dibromo derivatives.Several benzoheterocyclic molecules were converted with 1 to substitution or addition products, i.e. 2,3-dibromo-N-methylpyrrole, 3-bromobenzo/b/thiophene, and 2,3-dibromo-2,3-dihydrobenzofuran.In the series of ortho-alkyl disubstituted benzene derivatives, i.e. o-xylene, indane, and tetraline, where the Mills-Nixon effect was established with various electrophilic reagents, bromination reactions with 2 showed higher β-selectivity than the corresponding reactions with bromine.The rate of bromination in various alkyl substituted benzenes with reagent 2 depended on the magnitude of the alkyl group, as well as the para/ortho regioselectivity, amounting to 100percent in the case of tert-butylbenzene.
Novel bromination method for anilines and anisoles using NH 4Br/H2O2 in CH3COOH
Krishna Mohan,Narender,Srinivasu,Kulkarni,Raghavan
, p. 2143 - 2152 (2004)
A simple, efficient, regioselective, environmentally safe, and economical method for the oxybromination of anilines and anisoles without catalyst is reported. The electrophilic substitution of bromine generated in situ from ammonium bromide as a bromine source and hydrogen peroxide as an oxidant for the first time.
Silica-supported quinolinium tribromide: A recoverable solid brominating reagent for regioselective monobromination of aromatic amines
Li, Zheng,Sun, Xiunan,Wang, Lue,Li, Yanbo,Ma, Yuanhong
, p. 496 - 501 (2010)
Silica-supported quinolinium tribromide was synthesized and found to be an efficient, stable, and recoverable solid brominating reagent for the regioselective monobromination of aromatic amines. This protocol has advantages of high yield, mild condition and simple work-up procedure.
Synthesis of new 3-(2-Chloroquinolin-3-yl)-5-phenylisoxazole derivatives via click chemistry approach
Ferna?ndez-Galleguillos, Carlos,Saavedra, Luis A.,Gutierrez, Margarita
, p. 365 - 371 (2014)
Herein, we report the synthesis of new substituted 3-(2-chloroquinolin-3- yl)-5-phenylisoxazole (3a-j) by click chemistry in good to moderate yields. This approach is based on the regioselective copper(I)-catalyzed cycloaddition between different nitrile oxides derived from 2-chloroquinoline- 3-carbaldehyde (2a-j) and phenylacetylene. Finally these derivatives were screened for their antibacterial evaluation in vitro against three Gram-negative clinical bacteria: Escherichia coli, Pseudomonas aeruginosa and Acinetobacter baumannii using standard methods.
Disulfide-Catalyzed Iodination of Electron-Rich Aromatic Compounds
Iida, Keisuke,Ishida, Shunsuke,Watanabe, Takamichi,Arai, Takayoshi
, (2019)
Herein, a disulfide-catalyzed electrophilic iodination of aromatic compounds using 1,3-diiodo-5,5-dimethylhydantoin (DIH) has been developed. The disulfide activates DIH as a Lewis base to promote the iodination reaction in acetonitrile under mild conditions. This system is applicable to a wide range of electron-rich aromatic compounds, including acetanilide, anisole, imidazole, and pyrazole derivatives.
N-aryl-2-aminobenzimidazoles: Novel, efficacious, antimalarial lead compounds
Ramachandran, Sreekanth,Hameed P., Shahul,Srivastava, Abhishek,Shanbhag, Gajanan,Morayya, Sapna,Rautela, Nikhil,Awasthy, Disha,Kavanagh, Stefan,Bharath, Sowmya,Reddy, Jitendar,Panduga, Vijender,Prabhakar,Saralaya, Ramanatha,Nanduri, Robert,Raichurkar, Anandkumar,Menasinakai, Sreenivasaiah,Achar, Vijayashree,Jiménez-Díaz, María Belén,Martínez, María Santos,Angulo-Barturen, I?igo,Ferrer, Santiago,Sanz, Laura María,Gamo, Francisco Javier,Duffy, Sandra,Avery, Vicky M.,Waterson, David,Lee, Marcus C. S.,Coburn-Flynn, Olivia,Fidock, David A.,Iyer, Pravin S.,Narayanan, Shridhar,Hosagrahara, Vinayak,Sambandamurthy, Vasan K.
, p. 6642 - 6652 (2014)
From the phenotypic screening of the AstraZeneca corporate compound collection, N-aryl-2-aminobenzimidazoles have emerged as novel hits against the asexual blood stage of Plasmodium falciparum (Pf). Medicinal chemistry optimization of the potency against Pf and ADME properties resulted in the identification of 12 as a lead molecule. Compound 12 was efficacious in the P. berghei (Pb) model of malaria. This compound displayed an excellent pharmacokinetic profile with a long half-life (19 h) in rat blood. This profile led to an extended survival of animals for over 30 days following a dose of 50 mg/kg in the Pb malaria model. Compound 12 retains its potency against a panel of Pf isolates with known mechanisms of resistance. The fast killing observed in the in vitro parasite reduction ratio (PRR) assay coupled with the extended survival highlights the promise of this novel chemical class for the treatment of malaria.
Fast and efficient bromination of aromatic compounds with ammonium bromide and Oxone
Naresh, Mameda,Arun Kumar, Macharla,Mahender Reddy, Marri,Swamy, Peraka,Nanubolu, Jagadeesh Babu,Narender, Nama
, p. 1497 - 1504 (2013)
A highly efficient, rapid and regioselective protocol was developed for the ring bromination of aromatic compounds under mild conditions with ammonium bromide as a source of bromine source and Oxone (potassium peroxysulfate) as an oxidant. No metal catalyst or acidic additive is required. A variety of aromatic compounds, including methoxy, hydroxy, amino, and alkyl arenes, reacted smoothly to give the corresponding monobrominated products in good to excellent yields in very short reaction times. Moreover, dibromination of deactivated anilines to give the corresponding dibromides proceeded in high yields. Interestingly, 1-(2-naphthyl)ethanone provided a ring-brominated product. Georg Thieme Verlag Stuttgart . New York.
H2O2/SOCl2: a useful reagent system for the conversion of thiocarbonyls to carbonyl compounds
Bahrami, Kiumars,Khodaei, Mohammad M.,Farrokhi, Azita
, p. 7658 - 7661 (2009)
The H2O2/SOCl2 reagent system has been used as a new and efficient reagent for deprotection of thiocarbonyls to carbonyl compounds. The salient features of this protocol are short reaction times, good chemoselectivity, clean reaction profiles, and simple work-up that preclude the use of toxic solvents.
Ethyl 2-Cyano-2-(2-nitrobenzenesulfonyloxyimino) Acetate (ortho-NosylOXY)-Mediated Double Beckmann Rearrangement of Ketoximes under Microwave Irradiation: A Mechanistic Perception
Dev, Dharm,Kalita, Tapasi,Mondal, Tanmay,Mandal, Bhubaneswar
, p. 1427 - 1435 (2021/01/04)
A method for Beckmann rearrangement using ethyl 2-cyano-2-(2-nitrobenzenesulfonyloxyimino) acetate (o-NosylOXY) under microwave irradiation is reported. Ketoximes (19 examples) are converted to the corresponding amides/lactams with 69–97% yields in ～10 minutes without any Lewis acid or co-catalyst. This is an example of halogen-free organocatalytic Beckmann rearrangement. Nuclear magnetic resonance (NMR)- and high-resolution mass spectrometry (HRMS)-based detailed mechanistic investigation suggest that o-NosylOXY acts as an initiator. Such initiators are reported before based on density functional theory (DFT) calculations. However, we report here the HRMS signatures of two transient intermediates, the nitrilium ion and the nitrilium ion's dimeric species. Rigorous NMR-based investigation of the reaction mechanism is performed. Our results indicate that the reported Beckmann rearrangement proceeds via two consecutive rearrangements. (Figure presented.).
The improvement of photovoltaic performance of quinoline-based dye-sensitized solar cells by modification of the auxiliary acceptors
?i?man, ?lkay,Arkan, Burcu,Arslan, Bar?? Se?kin,Avc?, Davut,Derin, Yavuz,Gezgin, Merve,Nebio?lu, Mehmet,Tutar, Ahmet
, (2020/10/07)
Three new dyes containing diphenylamine as electron donor, benzene (BIM1), benzothiadiazole (BTD) (BIM2) and N-ethylhexylbenzotriazole (BTZ) (BIM3) as auxiliary electron acceptors, quinoline as π-bridge and cyanoacrylic acid as anchoring group were synthesized in D-A-π-A structure for use in dye-sensitized solar cells (DSSCs). The optical, electrochemical, theoretical and photovoltaic methods were performed to understand the auxiliary acceptor influence on the performance of these dyes. Compared to the other dyes, the DSSC with dye BIM3 slightly increases the open circuit voltage (Voc) owing to the retardation of charge recombination by BTZ. However, replacement of benzene or BTZ by BTD unit causes a large red shift of the absorption spectra, leading BIM2 cell to produce the highest short circuit current density (Jsc). Thus, among the three D-A-π-A dyes, BIM2 is determined to be the most efficient dye, which reached a Voc of 0.627 V and Jsc of 11.53 mA cm–2, corresponding to an overall power conversion efficiency of 5.21 % in the presence of chenodeoxycholic acid (CDCA) as the coadsorbent. These results suggest that the insertion of benzothiadiazole as auxiliary acceptor into quinoline-based D-A-π-A dyes can effectively improve photovoltaic performance of DSSCs.
Synthesis, crystal structure, anticancer and molecular docking studies of quinolinone-thiazolidinone hybrid molecules
Krishnappagowda, Lokanath Neratur,Kumar, Vasantha,Pai, Vinitha R.,Poojary, Boja,Rai, Vaishali M.,Shivalingegowda, Naveen,Udupi, Vishwanatha
, (2021/08/12)
A new series of quinolone-thiazolidinone hybrid molecules 8a-o were prepared. Quinoline compounds were synthesized by Meth-Cohn synthesis and were condensed with 2,3-disubstituted thiazolidinone. These molecules were screened for their anticancer activities against MDA-MB-231 and MCF-7 cell line using MTT assay. Potent compounds were tested for their cytotoxicity on normal HEK 293 cell lines and most potent compound was tested for its cell cycle analysis. Molecular docking and molecular dynamic studies were performed on human N-acetyl transferase (hNAT-1) protein using Schrodinger molecular docking toolkit. Compound 8n emerged as potent with IC50 8.16?μM against MDA-MB-231 cell line followed by 8e with IC50 17.68?μM. Compound 8n arrested cell cycle at G2/M phase and was non-toxic to human normal kidney cell line. The potent compound 8n binds well with human NAT-1 protein with remarkable hydrogen bonding and π–π interactions. Molecular dynamic studies of 8n further confirm the target for these molecules. Target quinolinone-thiazolidinones were found to be new class of compounds targeting hNAT-1 and can serve as new lead compounds in drug discovery.
