- Selective Bromination of β-Positions of Porphyrin by Self-Catalytic Behaviour of VOTPP: Facile Synthesis, Electrochemical Redox Properties and Catalytic Application
-
Oxidovanadium(IV) complex of β-octabromo-meso-tetraphenylporphyrin, {[VIVO(TPPBr8)], 2} was synthesized by self-catalytic oxidative bromination of meso-tetraphenylporphyrinatooxidovanadium(IV) {[VIVO(TPP), 1} in excellent yield under mild conditions at 25 °C and its structure was confirmed by single crystal X-ray study. UV-Vis and 1H NMR spectra further confirmed that the meso-phenyl rings are not brominated and thus emphasizes on the selectivity as well as synthetic importance of this catalytic method. In the presence of substrates e. g. phenol derivatives, 1 biomimics the vanadium bromoperoxidase (VBPO) enzyme and catalyses the oxidative bromination of substrates in water at 25 °C. Remarkably, 2 also catalyses the oxidative bromination of phenol derivatives under similar reaction conditions with very high turnover frequency (TOF) values (ca. 29 s?1) along with its recyclability. It was found that 2 showed superior catalytic performance as compared to 1 because of its electron deficient nature due to electron withdrawing bromo substituents and robust saddle shaped nonplanar structure (further supported by DFT studies).
- Maurya, Mannar R.,Prakash, Ved,Avecilla, Fernando,Sankar, Muniappan
-
p. 1685 - 1694
(2021/05/03)
-
- Identification of a novel allosteric GLP-1R antagonist HTL26119 using structure- based drug design
-
A series of novel allosteric antagonists of the GLP-1 receptor (GLP-1R), exemplified by HTL26119, are described. SBDD approaches were employed to identify HTL26119, exploiting structural understanding of the allosteric binding site of the closely related Glucagon receptor (GCGR) (Jazayeri et al., 2016) and the homology relationships between GCGR and GLP-1R. The region around residue C3476.36b of the GLP-1R receptor represents a key difference from GCGR and was targeted for selectivity for GLP-1R.
- O'Brien, Alistair,Andrews, Stephen P.,Baig, Asma H.,Bortolato, Andrea,Brown, Alastair J.H.,Brown, Giles A.,Brown, Sue H.,Christopher, John A.,Congreve, Miles,Cooke, Robert M.,De Graaf, Chris,Errey, James C.,Fieldhouse, Charlotte,Jazayeri, Ali,Marshall, Fiona H.,Mason, Jonathan S.,Mobarec, Juan Carlos,Okrasa, Krzysztof,Steele, Kelly N.,Southall, Stacey M.,Teobald, Iryna,Watson, Steve P.,Weir, Malcolm
-
supporting information
(2019/09/30)
-
- Ammonium Salt-Catalyzed Highly Practical Ortho-Selective Monohalogenation and Phenylselenation of Phenols: Scope and Applications
-
An ortho-selective ammonium chloride salt-catalyzed direct C-H monohalogenation of phenols and 1,1′-bi-2-naphthol (BINOL) with 1,3-dichloro-5,5-dimethylhydantoin (DCDMH) as the chlorinating agent has been developed. The catalyst loading was low (down to 0.01 mol %) and the reaction conditions were very mild. A wide range of substrates including BINOLs were compatible with this catalytic protocol. Chlorinated BINOLs are useful synthons for the synthesis of a wide range of unsymmetrical 3-aryl BINOLs that are not easily accessible. In addition, the same catalytic system can facilitate the ortho-selective selenylation of phenols.
- Xiong, Xiaodong,Yeung, Ying-Yeung
-
p. 4033 - 4043
(2018/05/22)
-
- 1,1,2,2-Tetrahydroperoxy-1,2-Diphenylethane: An efficient and high oxygen content oxidant in various oxidative reactions
-
Several oxidative approaches namely thiocyanation of aromatic compounds, epoxidation of alkenes, amidation of aromatic aldehydes, epoxidation of α β-unsaturated ketones, oxidation of sulfides to sulfoxides and sulfones, bayer-villeger reaction, bromination and iodation of aniline and phenol derivatives oxidative esterification, oxidation of pyridines and oxidation of secondary, allylic and benzyllic alcohols were carried out using 1,1,2,2-Tetrahydroperoxy-1,2-Diphenylethane as the potential solid oxidant which can be stored for several months without any loss in its activity. All of the procedures were accomplished via mild reaction conditions and the products were afforded in high yields and short reaction times.
- Khosravi, Kaveh,Naserifar, Shirin
-
supporting information
p. 6584 - 6592
(2018/10/05)
-
- NEW ARYL-BENZOCYCLOALKYL AMIDE DERIVATIVES
-
The invention provides novel compounds having the general formula (I) wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, A1, A2 and n are as described herein, compositions including the compounds and methods of using the compounds.
- -
-
Paragraph 0372-0373
(2013/03/26)
-
- NEW BIARYL AMIDE DERIVATIVES
-
The invention provides novel compounds having the general formula (I) wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12 and A are as described herein, compositions including the compounds and methods of using the compounds.
- -
-
Page/Page column 19-20
(2012/07/13)
-
- NEW BIARYL AMIDE DERIVATIVES
-
The invention provides novel compounds having the general formula (I) wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12 and A are as described herein, compositions including the compounds and methods of using the compounds.
- -
-
Page/Page column 48
(2012/07/14)
-
- NEW ARYL-BENZOCYCLOALKYL AMIDE DERIVATIVES
-
The invention provides novel compounds having the general Formula (I), wherein R1, R2, R3, R4 R5, R6, R7, R8 R9, R10, R11, R12, A1, A2 and n are as described herein, compositions including the compounds and methods of using the compounds.
- -
-
Page/Page column 67
(2012/08/08)
-
- Green, mild and efficient bromination of aromatic compounds by HBr promoted by trans-3,5-dihydroperoxy-3,5-dimethyl-1,2-dioxolane in water as a solvent
-
A combination of HBr and trans-3,5-dihydroperoxy-3,5-dimethyl-1,2-dioxolane as a new and powerful oxidant was found effective for facile bromination of different aromatic compounds at room temperature in water as a green solvent. Mild reaction conditions, high selectivity and yield, high reaction rate and non-toxicity are some of the major advantages of this synthetic protocol.
- Khosravi, Kaveh,Kazemi, Samira
-
experimental part
p. 387 - 390
(2012/05/20)
-
- Regioselective bromination and iodination of aromatic substrates promoted by trans-3,5-dihydroperoxy-3,5-dimethyl-1,2-dioxolane
-
Selective and efficient bromination and iodination of aromatic compounds by ammonium bromide and ammonium iodide, respectively, under promotion of trans-3,5-dihydroperoxy-3,5-dimethyl-1,2-dioxolane have been explored. Mild reaction conditions, high selectivity and yield, and high reaction rate are some of the major advantages of this synthetic method.
- Azarifar, Davood,Khosravi, Kaveh,Najminejad, Zohreh,Soleimani, Khadijeh
-
experimental part
p. 321 - 326
(2012/08/14)
-
- Aerobic oxybromination of phenols catalyzed by sodium nitrite under mild conditions
-
An efficient catalytic system for oxybromination of phenols under mild conditions has been developed, which utilizes sodium nitrite as the catalyst, dioxygen or air as the terminal oxidant, aqueous hydrobromic acid or molecular bromine as the bromine resource. From both the atom-economic and environmental points of view, the developed protocol is expected to provide a valuable synthetic method for practical applications in laboratory or industry. Georg Thieme Verlag Stuttgart - New York.
- Xu, Li,Wang, Yong,Wen, Xin,Ding, Chengrong,Zhang, Guofu,Liang, Xinmiao
-
supporting information; experimental part
p. 2265 - 2269
(2011/10/31)
-
- Practical synthesis of a potent bradykinin B1 antagonist via enantioselective hydrogenation of a pyridyl N-acyl enamide
-
(Chemical Equation Presented) A practical and efficient synthesis of bradykinin B1 antagonist 1 is described. A convergent strategy was utilized which involved synthesis of three fragments: 3, 6, and 7. Cross coupling of fragments 6 and 7 followed by amidation with 3 enabled efficient synthesis of 1 in 19 steps total, a 35% overall yield from commercially available pyridine 10. The key to the success of the synthesis was the development of a fluorodenitration step to install the fluorine in pyridine 7 and a catalytic enantioselective hydrogenation of N-acyl enamide 9 to set the stereochemistry.
- O'Shea, Paul D.,Gauvreau, Danny,Gosselin, Francis,Hughes, Greg,Nadeau, Christian,Roy, Amelie,Shultz, C. Scott
-
supporting information; experimental part
p. 4547 - 4553
(2009/09/30)
-
- Regioselective bromination of activated aromatic substrates with a ZrBr4/diazene mixture
-
A regioselective method for the bromination of phenols, ethers and anilines using a ZrBr4/diazene mixture is described. The reaction takes place under mild reaction conditions and the bromine atom adds first at the para unsubstituted position with respect to the OH, OR or NR2 group of the activated aromatic substrate. Less reactive compounds such as toluene, phenyl acetate, benzonitrile and trifluoromethylbenzene remain intact under the same conditions.
- Stropnik, Tadej,Bombek, Sergeja,Ko?evar, Marijan,Polanc, Slovenko
-
p. 1729 - 1733
(2008/09/18)
-
- A new class of bradykinin B1 receptor antagonists with high oral bioavailability and minimal PXR activity
-
The design and synthesis of a novel class of human bradykinin B1 antagonists featuring difluoroethyl ether and isoxazole carboxamide moieties are disclosed. Compound 7g displayed excellent pharmacokinetic properties, efficient ex vivo receptor occupancy, and low potential for P450 induction via PXR activation.
- Feng, Dong-Mei,DiPardo, Robert M.,Wai, Jenny M.,Chang, Ronald K.,Di Marco, Christina N.,Murphy, Kathy L.,Ransom, Richard W.,Reiss, Duane R.,Tang, Cuyue,Prueksaritanont, Thomayant,Pettibone, Douglas J.,Bock, Mark G.,Kuduk, Scott D.
-
p. 682 - 687
(2008/09/19)
-
- Pyrazine Derivatives
-
The present invention relates to compounds of the formula and pharmaceutically acceptable salts and solvates thereof, to processes for the preparation of, intermediates used in the preparation of, and compositions containing such compounds and the uses of such compounds for the treatment of pain.
- -
-
Page/Page column 31
(2008/06/13)
-
- Simple bromination of activated arenes by IBX amide resin and tetraethyl-ammonium bromide
-
A mild and operationally simple method of brominating activated aromatic compounds using a polymer supported IBX reagent (IBX amide resin) and tetraethylammonium bromide (TEAB) was developed. The activated aromatics, when reacted with IBX amide resin in the presence of TEAB, were easily converted into the brominated aromatics in high yields (>80%) at room temperature.
- Kim, Duk-Ki,Chung, Woo-Jae,Lee, Yoon-Sik
-
p. 279 - 282
(2007/10/03)
-
- Identification of hydroxylated PCB metabolites and other phenolic halogenated pollutants in human blood plasma
-
A growing number of studies have reported phenolic halogenated compounds (PHCs) that are retained in the blood of humans and wildlife. These PHCs may be industrial chemicals; metabolites thereof, as in the case with polychlorobiphenylols (OH-PCBs); or of natural origin. The present study was aimed to identify hitherto unknown PHCs in human plasma with chemical structures that are consistent to PHCs known to possess endocrine-disrupting activity. For this purpose, samples of blood plasma from 10 randomly selected male blood donors from Sweden were pooled and analyzed by GC/ECD and GC/MS. Brominated, bromochlorinated, and chlorinated methyl derivatives of phenols and OH-PCBs were synthesized to be used as authentic reference standards. More than 100 PHCs were indicated in the plasma, and among those a total of 9 monocyclic brominated or chlorinated phenol-, guaiacol-, and/or catechol-type compounds were identified as their methylated derivatives. The two major compounds were 2,4,6-tribromophenol and pentachlorophenol. Thirty-eight OH-PCB congeners were structurally identified on two GC columns of different polarity. The origin of the OH-PCB metabolites in the context of their parent PCB congeners are suggested. Other PHCs identified in the male plasma were Triclosan (5-chloro-2-[2,4-dichlorophenoxy] phenol), a common bactericide; 4-hydroxy-heptachlorostyrene, a metabolite of octachlorostyrene; and 3,5-dibromo-2-(2,4-dibromophenoxy)phenol, a natural compound and a potential metabolite of polybrominated diphenyl ethers.
- Hovander,Malmberg,Athanasiadou,Athanassiadis,Rahm,Bergman,Wehler, E. Klasson
-
p. 105 - 117
(2007/10/03)
-
- Chemical modification of chlorophenols for their gas-chromatographic determination in water
-
A two-stage chemical modification involving bromination in aqueous solution followed by acylation of the resulting bromochlorophenols in the extract was studied as a way to decrease the detection limit of chlorophenols in water.
- Korenman,Gruzdev,Kondratenok
-
p. 1526 - 1530
(2007/10/03)
-
- Kinetics of Hydrolysis of Mono 6-Bromo-2,4-dichlorophenyl Phosphate in Acidic and Alkaline Media
-
Hydrolysis of mono 6-bromo-2,4-dichlorophenyl phosphate as cyclohexylammonium salt has been carried out in the pH range, 1.24 to 10.0 in aq. dioxan media at 90 deg C.Neutral species although shown to be present by salt effect study, does not seem to participate in the reaction at the lowest pH value (1.24) examined.Mononegative species, however, in the pH region upto 7 gets hydrolysed unimolecularly.This is also evident from the low entropy value, isokinetic relationship (β = 333.3 deg K) and solvent effect studies and thus lends strong support for the intramolecular general acid catalysis by the hydroxyl group of the monoanion.The dinegative species is rather inert between pH 4 and 7.Its contribution to the overall rate becomes significant after pH 7.Its reactivity depends largely upon the highly basic nature of the leaving group caused by +M effect of three halogen substituents. pK1 and pK2 values have been determined to be 1.17 and 6.8 respectively.The monoester and the parent compound have also been tested for their antifungal activity.
- Gupta, H. M.,Prabha, S.
-
p. 321 - 324
(2007/10/02)
-
- Kinetics and Mechanism of Acid Hydrolysis of Di-6-bromo-2,4-dichlorophenyl Phosphate
-
Hydrolysis of di-6-bromo-2,4-dichlorophenyl phosphate has been pursued in HCl (0.03-7M) in dioxan water (16percent) at 90 deg C.Ionic strength data upto 3 μ, requires the participation of neutral (I) as weel as conjugate acid (II) forms.The slopes exhibit a fixed contribution irrespective of the value of μ.Unimolecular behaviour for the neutral form has been decided by temperature effect studies.Unusual presence of (I) alone has also been highlighted beyond 4M, where the maximum appears as usual.II, however, hydrolyses bimolecularly via monoester formation.Mirror method calculation are helpful to eliminate monoester formation during acid hydrolysis.Solvent isotope effect study favours specific acid catalysis.The diester involves P-O bond rupture which is strengthened by comparative kinetic data.
- Gupta, H.M.,Prabha, S.
-
p. 577 - 580
(2007/10/02)
-