3007-97-4Relevant academic research and scientific papers
New gold (I) complexes with 5-aromatic ring-1, 3, 4-oxadiazole-2-thione and triphenylphosphine as potential multifunctional materials
Zhao, Yu Qiang,Zhou, Jie,He, Renze,Wang, Guang Ke,Miao, Lan Xi,Xie, Xiao Guang,Zhou, Ying
supporting information, (2020/12/02)
Three new gold (I) complexes (4a, 4b, 4c) with 5-aromatic ring-1, 3, 4-oxadiazole-2-thione and triphenylphosphine as ligands were synthesized. Structures of 4a and 4b were determined through X-ray single-crystal diffraction, and it displayed that 4a and 4b had the same metal coordination pattern, wherein the ligand was coordinated by the sulfur atom to the central metal ion of gold (I). The optical properties of these gold (I) complexes were studied both in solution and in solid-state. In DMSO, 4a and 4b peaked at 415 nm and 443 nm, respectively, and the CIE coordinates of 4a and 4b in the solid-state were in the green area namely, (0.26, 0.46) and (0.24, 0.41). HOMO/LUMO levels and bandgaps of 4a, 4b and 4c were assessed by UV spectrum estimation, electrochemical method, and theoretical calculations. The observation hinted that the photophysical properties and energy levels of these gold (I) complexes can be adjusted by the introduction of different substituent aromatic rings at the 5-position of the 1, 3, 4-oxadiazole-2-thiol moiety. The findings of good optical, electrochemical and thermal properties of these new gold (I) complexes demonstrated their potential in the future studies as multifunctional materials.
4-Amino-1,2,4-triazole-3-thione-derived Schiff bases as metallo-β-lactamase inhibitors
Baud, Damien,Bebrone, Carine,Becker, Katja,Benvenuti, Manuela,Cerboni, Giulia,Chelini, Giulia,Cutolo, Giuliano,De Luca, Filomena,Docquier, Jean-Denis,Feller, Georges,Fischer, Marina,Galleni, Moreno,Gavara, Laurent,Gresh, Nohad,Kwapien, Karolina,Legru, Alice,Mangani, Stefano,Mercuri, Paola,Pozzi, Cecilia,Sannio, Filomena,Sevaille, Laurent,Tanfoni, Silvia,Verdirosa, Federica,Berthomieu, Dorothée,Bestgen, Beno?t,Frère, Jean-Marie,Hernandez, Jean-Fran?ois
supporting information, (2020/09/16)
Resistance to β-lactam antibiotics in Gram-negatives producing metallo-β-lactamases (MBLs) represents a major medical threat and there is an extremely urgent need to develop clinically useful inhibitors. We previously reported the original binding mode of 5-substituted-4-amino/H-1,2,4-triazole-3-thione compounds in the catalytic site of an MBL. Moreover, we showed that, although moderately potent, they represented a promising basis for the development of broad-spectrum MBL inhibitors. Here, we synthesized and characterized a large number of 4-amino-1,2,4-triazole-3-thione-derived Schiff bases. Compared to the previous series, the presence of an aryl moiety at position 4 afforded an average 10-fold increase in potency. Among 90 synthetic compounds, more than half inhibited at least one of the six tested MBLs (L1, VIM-4, VIM-2, NDM-1, IMP-1, CphA) with Ki values in the μM to sub-μM range. Several were broad-spectrum inhibitors, also inhibiting the most clinically relevant VIM-2 and NDM-1. Active compounds generally contained halogenated, bicyclic aryl or phenolic moieties at position 5, and one substituent among o-benzoic, 2,4-dihydroxyphenyl, p-benzyloxyphenyl or 3-(m-benzoyl)-phenyl at position 4. The crystallographic structure of VIM-2 in complex with an inhibitor showed the expected binding between the triazole-thione moiety and the dinuclear centre and also revealed a network of interactions involving Phe61, Tyr67, Trp87 and the conserved Asn233. Microbiological analysis suggested that the potentiation activity of the compounds was limited by poor outer membrane penetration or efflux. This was supported by the ability of one compound to restore the susceptibility of an NDM-1-producing E. coli clinical strain toward several β-lactams in the presence only of a sub-inhibitory concentration of colistin, a permeabilizing agent. Finally, some compounds were tested against the structurally similar di-zinc human glyoxalase II and found weaker inhibitors of the latter enzyme, thus showing a promising selectivity towards MBLs.
Porous organic cage stabilised palladium nanoparticles: Efficient heterogeneous catalysts for carbonylation reaction of aryl halides
Zhang, Yong,Xiong, Yu,Ge, Jin,Lin, Rui,Chen, Chen,Peng, Qing,Wang, Dingsheng,Li, Yadong
supporting information, p. 2796 - 2799 (2018/03/21)
Porous organic cage stabilised palladium nanoparticles were successfully prepared using methanol as a mild reductant. The as-prepared porous composite materials show high catalytic activity for the carbonylation reaction of aryl halides under mild conditions.
1,2,4-Triazole-3-thione Compounds as Inhibitors of Dizinc Metallo-β-lactamases
Sevaille, Laurent,Gavara, Laurent,Bebrone, Carine,De Luca, Filomena,Nauton, Lionel,Achard, Maud,Mercuri, Paola,Tanfoni, Silvia,Borgianni, Luisa,Guyon, Carole,Lonjon, Pauline,Turan-Zitouni, Gülhan,Dzieciolowski, Julia,Becker, Katja,Bénard, Lionel,Condon, Ciaran,Maillard, Ludovic,Martinez, Jean,Frère, Jean-Marie,Dideberg, Otto,Galleni, Moreno,Docquier, Jean-Denis,Hernandez, Jean-Fran?ois
, p. 972 - 985 (2017/06/27)
Metallo-β-lactamases (MBLs) cause resistance of Gram-negative bacteria to β-lactam antibiotics and are of serious concern, because they can inactivate the last-resort carbapenems and because MBL inhibitors of clinical value are still lacking. We previously identified the original binding mode of 4-amino-2,4-dihydro-5-(2-methylphenyl)-3H-1,2,4-triazole-3-thione (compound IIIA) within the dizinc active site of the L1 MBL. Herein we present the crystallographic structure of a complex of L1 with the corresponding non-amino compound IIIB (1,2-dihydro-5-(2-methylphenyl)-3H-1,2,4-triazole-3-thione). Unexpectedly, the binding mode of IIIB was similar but reverse to that of IIIA. The 3 D structures suggested that the triazole–thione scaffold was suitable to bind to the catalytic site of dizinc metalloenzymes. On the basis of these results, we synthesized 54 analogues of IIIA or IIIB. Nineteen showed IC50 values in the micromolar range toward at least one of five representative MBLs (i.e., L1, VIM-4, VIM-2, NDM-1, and IMP-1). Five of these exhibited a significant inhibition of at least four enzymes, including NDM-1, VIM-2, and IMP-1. Active compounds mainly featured either halogen or bulky bicyclic aryl substituents. Finally, some compounds were also tested on several microbial dinuclear zinc-dependent hydrolases belonging to the MBL-fold superfamily (i.e., endonucleases and glyoxalase II) to explore their activity toward structurally similar but functionally distinct enzymes. Whereas the bacterial tRNases were not inhibited, the best IC50 values toward plasmodial glyoxalase II were in the 10 μm range.
Room Temperature Carbonylation of (Hetero) Aryl Pentafluorobenzenesulfonates and Triflates using Palladium-Cobalt Bimetallic Catalyst: Dual Role of Cobalt Carbonyl
Joseph, Jayan T.,Sajith, Ayyiliath M.,Ningegowda, Revanna C.,Shashikanth, Sheena
, p. 419 - 425 (2017/02/10)
An efficient method for the carbonylation of (hetero) aryl pentafluorobenzenesulfonates and triflates under exceptionally mild conditions using palladium/dicobalt octacarbonyl [Pd/Co2(CO)8] has been developed. Besides acting as carbon monoxide (CO) source, Co2(CO)8enhances the reaction rate by accelerating the CO insertion through an in situ generated bimetallic palladium cobalt tetracarbonyl [Pd-Co(CO)4] complex. Under the optimized reaction condition, carbonylation of a wide range of activated and deactivated, as well as sterically hindered and heteroaromatic, substrates proceeded efficiently at room temperature. The high chemoselectivity and improved synthesis of biologically relevant Isoguvacine and Lazabemide intermediates highlights its scope as a valuable synthetic method. The generality of this protocol was further extended to other electrophiles (bromides, chlorides and tosylates). (Figure presented.).
SO2F2-Mediated One-Pot Synthesis of Aryl Carboxylic Acids and Esters from Phenols through a Pd-Catalyzed Insertion of Carbon Monoxide
Fang, Wan-Yin,Leng, Jing,Qin, Hua-Li
, p. 2323 - 2331 (2017/09/06)
A one-pot Pd-catalyzed carbonylation of phenols into their corresponding aryl carboxylic acids and esters through the insertion of carbon monoxide has been developed. This procedure offers a direct synthesis of aryl carboxylic acids and esters from inexpensive and abundant starting materials (phenols, SO2F2 and CO) under mild conditions. This method tolerates a broad range of functional groups and is also applicable for the modification of complicated natural products.
Method of converting amide and urea into ester
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Paragraph 0057-0059, (2017/08/30)
The invention provides a method of converting amide and urea into ester. In the method, different types of amide and urea are used as substrate, alcohol or phenol is used as nucleophile, iron salt is used as catalyst, and acid is used as additive, the conversion of amide and urea into ester is achieved under a mild condition. The method is characterized in that cheap iron salt is used as the catalyst, the commercialized amide, urea, and alcohol are used as the substrate, and the conversion of amide to ester is achieved in one step. The method has the advantages that the reaction condition is mild, the raw materials are cheap and easy to obtain, the reaction substrate is wide in adaptability, the selectivity and yield of the product are very high, the product is green and environmentally friendly and the like, and the method has good prospects for industrial applications.
Practical: In situ -generation of phosphinite ligands for palladium-catalyzed carbonylation of (hetero)aryl bromides forming esters
Wang, Lin,Neumann, Helfried,Spannenberg, Anke,Beller, Matthias
supporting information, p. 7469 - 7472 (2017/07/12)
An effective method for alkoxycarbonylation of (hetero)aryl bromides is developed in the presence of in situ-generated phosphinite ligands tBu2POR (R = nBu, nPr, Et or Me). For this purpose commercially available tBu2PCl was used as the pre-ligand in the presence of different alcohols. For the first time cross coupling reactions with two alcohols-one generating the ligand, the other used as substrate-were developed. Through this method, ligand optimization can be performed in a more efficient manner and the desired products could be obtained with good yields and selectivity.
Synthesis of naphthalenecarboxylic and naphthalenedicarboxylic acids from naphthalene, carbon tetrachloride, and alcohols in the presence of iron catalysts
Baiguzina,Erokhina,Khusnutdinov
, p. 389 - 395 (2017/05/01)
Alkyl naphthalenecarboxylates and dialkyl naphthalenedicarboxylates have been synthesized by reactions of naphthalene and its derivatives with alcohols and carbon tetrachloride in the presence of iron catalysts.
Metal-free aerobic oxidative esterification of aldehydes in the presence of cyanide
Kim, Yoo-Jin,Cheon, Cheol-Hong
supporting information, p. 2055 - 2061 (2015/08/18)
A metal-free aerobic oxidative esterification of aldehydes in the presence of cyanide is described. Various aromatic aldehydes and sterically congested alcohols were amenable to this protocol. In addition, this method could be extended to the preparation of thioesters with a thiol in place of an alcohol. Furthermore, the cyanide-mediated aerobic oxidation of aldehydes was applied to the synthesis of lactones via intramolecular esterification in the absence of an alcohol.
