- Pleuromutilin derivative with 1, 3, 4-oxadiazole side chain and preparation and application thereof
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The invention belongs to the field of medicinal chemistry, and particularly relates to a pleuromutilin derivative with a 1, 3, 4-oxadiazole side chain and preparation and application thereof The pleuromutilin derivative with the 1, 3, 4-oxadiazole side chain is a compound shown in a formula 2 or a pharmaceutically acceptable salt thereof, and a solvent compound, an enantiomer, a diastereoisomer and a tautomer of the compound shown in the formula 2 or the pharmaceutically acceptable salt thereof or a mixture of the solvent compound, the enantiomer, the diastereoisomer and the tautomer in any proportion, including a racemic mixture. The pleuromutilin derivative has good antibacterial activity, is especially suitable for being used as a novel antibacterial agent for systemic system infection of animals or human beings, and has good water solubility.
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Paragraph 0055-0056; 0070; 0090; 0092; 0095; 0102
(2021/07/24)
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- Development of Novel (+)-Nootkatone Thioethers Containing 1,3,4-Oxadiazole/Thiadiazole Moieties as Insecticide Candidates against Three Species of Insect Pests
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To improve the insecticidal activity of (+)-nootkatone, a series of 42 (+)-nootkatone thioethers containing 1,3,4-oxadiazole/thiadiazole moieties were prepared to evaluate their insecticidal activities against Mythimna separata Walker, Myzus persicae Sulzer, and Plutella xylostella Linnaeus. Insecticidal evaluation revealed that most of the title derivatives exhibited more potent insecticidal activities than the precursor (+)-nootkatone after the introduction of 1,3,4-oxadiazole/thiadiazole on (+)-nootkatone. Among all of the (+)-nootkatone derivatives, compound 8c (1 mg/mL) exhibited the best growth inhibitory (GI) activity against M. separata with a final corrected mortality rate (CMR) of 71.4%, which was 1.54- and 1.43-fold that of (+)-nootkatone and toosendanin, respectively; 8c also displayed the most potent aphicidal activity against M. persicae with an LD50 value of 0.030 μg/larvae, which was closer to that of the commercial insecticidal etoxazole (0.026 μg/larvae); and 8s showed the best larvicidal activity against P. xylostella with an LC50 value of 0.27 mg/mL, which was 3.37-fold that of toosendanin and slightly higher than that of etoxazole (0.28 mg/mL). Furthermore, the control efficacy of 8s against P. xylostella in the pot experiments under greenhouse conditions was better than that of etoxazole. Structure-activity relationships (SARs) revealed that in most cases, the introduction of 1,3,4-oxadiazole/thiadiazole containing halophenyl groups at the C-13 position of (+)-nootkatone could obtain more active derivatives against M. separata, M. persicae, and P. xylostella than those containing other groups. In addition, toxicity assays indicated that these (+)-nootkatone derivatives had good selectivity to insects over nontarget organisms (normal mammalian NRK-52E cells and C. idella and N. denticulata fries) with relatively low toxicity. Therefore, the above results indicate that these (+)-nootkatone derivatives could be further explored as new lead compounds for the development of potential eco-friendly pesticides.
- Cheng, Wanqing,Fan, Jiangping,Guo, Yong,Han, Meiyue,Ma, Nannan,Yan, Xiaoting,Yang, Ruige
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p. 15544 - 15553
(2022/01/03)
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- Design, synthesis, in vitro and in vivo evaluation against MRSA and molecular docking studies of novel pleuromutilin derivatives bearing 1, 3, 4-oxadiazole linker
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A class of pleuromutilin derivatives containing 1, 3, 4-oxadiazole were designed and synthesized as potential antibacterial agents against Methicillin-resistant staphylococcus aureus (MRSA). The ultrasound-assisted reaction was proposed as a green chemistry method to synthesize 1, 3, 4-oxadiazole derivatives (intermediates 85–110). Among these pleuromutilin derivatives, compound 133 was found to be the strongest antibacterial derivative against MRSA (MIC = 0.125 μg/mL). Furthermore, the result of the time-kill curves displayed that compound 133 could inhibit the growth of MRSA in vitro quickly (- 4.36 log10 CFU/mL reduction). Then, compound 133 (- 1.82 log10 CFU/mL) displayed superior in vivo antibacterial efficacy than tiamulin (- 0.82 log10 CFU/mL) in reducing MRSA load in mice thigh model. Besides, compound 133 exhibited low cytotoxicity to RAW 264.7 cells. Molecular docking studies revealed that compound 133 was successfully localized in the binding pocket of 50S ribosomal subunit (ΔGb = -10.50 kcal/mol). The results indicated that these pleuromutilin derivatives containing 1, 3, 4-oxadiazole might be further developed into novel antibiotics against MRSA.
- Liu, Jie,Zhang, Guang-Yu,Zhang, Zhe,Li, Bo,Chai, Fei,Wang, Qi,Zhou, Zi-Dan,Xu, Ling-Ling,Wang, Shou-Kai,Jin, Zhen,Tang, You-Zhi
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- Design and synthesis of novel furan, furo[2,3-d]pyrimidine and furo[3,2-e][1,2,4]triazolo[1,5-c]pyrimidine derivatives as potential VEGFR-2 inhibitors
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Novel furan 6a-c, furo[2,3-d]pyrimidine 7a-f, 9, 10a-f, 12a,b, 14a-d and furo[3,2-e][1,2,4]triazolo[1,5-c]pyrimidine 8a-f derivatives were designed based on their structural similarity to a previously described oxazole VEGFR-2 back pocket binding fragment. The designed compounds were synthesized and screened for their in vitro VEGFR-2 inhibitory activity where they exhibited good to moderate nanomolar inhibition with improved ligand efficiencies. 8b and 10c (IC50 = 38.72 ± 1.7 and 41.40 ± 1.8 nM, respectively) were equipotent to sorafenib and 6a, 6c, 7f, 8a, 8c, 10b, 10f, 12b, 14c and 14d showed good activity (IC50 = 43.31–98.31 nM). The furotriazolopyrimidines 8a-c and furopyrimidine derivative 10c were further evaluated for their in vitro antiproliferative activity against human umbilical vein endothelial cells (HUVECs) where 8b showed higher potency than sorafenib and resulted in cell cycle arrest at G2/M phase whereas 8c revealed good antiproliferative activity with cell cycle arrest at G1 phase. Moreover, 8a-c and 10c showed significant inhibitory effects on the invasion and migration of HUVECs. Molecular docking study was conducted to gain insight about the potential binding mode. The furo[3,2-e][1,2,4]triazolo[1,5-c]pyrimidine derivatives 8b and 8c represent interesting starting point for antiangiogenic compounds based on their activity and favorable drug likeness profiles.
- Abd El-Mageed, Menna M.A.,Eissa, Amal A.M.,Farag, Awatef El-Said,Osman, Essam Eldin A.
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- Synthesis, structural, spectroscopic, and thermal studies of some transition-metal complexes of a ligand containing the amino mercapto triazole moiety
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A new series of transition-metal complexes of Schiff base ligand containing the amino mercapto triazole moiety (HL) was prepared. The Schiff base and its metal complexes were elucidated by different spectroscopic techniques (infrared [IR], 1H nuclear magnetic resonance, UV–Visible, mass, and electron spin resonance [ESR]), and magnetic moment and thermal studies. Quantum chemical calculations have been carried out to study the structure of the ligand and some of its complexes. The IR spectra showed that the ligand is chelated with the metal ion in a neutral, tridentate, and bidentate manner using NOS and NO donors in complexes 1–6, 10–12, and 7 and 8, respectively, whereas it behaves in a monobasic tridentate fashion using NOS donor sites in copper(II) nitrate complex (9). The magnetic moment and electronic spectra data revealed octahedral and square pyramidal geometries for complexes 2, 11, 12, and 5–8 and 10, respectively. However, the other complexes were found to have tetrahedral (4), trigonal bipyramidal (1 and 3), and square planar (9) structures. Thermal studies revealed that the chelates with different crystallized solvents undergo different types of interactions and the decomposition pathway ended with the formation of metal oxygen (MO) and metal sulfur (MS) as final products. The ESR spectrum of copper(II) complex 10 is axial in nature with hyperfine splitting with 2B1g as a ground state. By contrast, complexes 7 and 8 undergo distortion around the Cu(II) center, affording rhombic ESR spectra. The HL ligand and some of its complexes were screened against two bacterial species. Data showed that complex 12 demonstrated a better antibacterial activity than HL ligand and other chelates.
- El-Nahas, Ahmed M.,Emam, Sanaa M.,Tolan, Dina A.
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- A de novo peroxidase is also a promiscuous yet stereoselective carbene transferase
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By constructing an in vivo-assembled, catalytically proficient peroxidase, C45, we have recently demonstrated the catalytic potential of simple, de novo-designed heme proteins. Here, we show that C45's enzymatic activity extends to the efficient and stereoselective intermolecular transfer of carbenes to olefins, heterocycles, aldehydes, and amines. Not only is this a report of carbene transferase activity in a completely de novo protein, but also of enzyme-catalyzed ring expansion of aromatic heterocycles via carbene transfer by any enzyme.
- Stenner, Richard,Steventon, Jack W.,Seddon, Annela,Anderson, J.L. Ross
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p. 1419 - 1428
(2020/01/28)
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- Pyridine triazole modified coumarin Cu2 + The preparation method of the fluorescent probe (by machine translation)
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Pyridine triazole modified coumarin Cu2 + fluorescent probe preparation method, the invention relates to a triazole modified coumarin Cu pyridine2 + Fluorescent probe is 3 - formyl - 7 - (diethylamino) coumarin Schiff base, the preparation method comprises preparing a compound (A), compound (B) and compound (C) 3 - formyl - 7 - (diethylamino) coumarin Schiff base three steps. 3 - Formyl - 7 - (diethylamino) coumarin Schiff base as a fluorescent probe in the detection of copper, has good light stability, high fluorescence quantum yield, storck large displacement and the like, can be fast, efficient, single-minded identification in an aqueous solution of copper ion, which is a fast high sensitivity fluorescence probe, other common metal ion has a stronger anti-interference capability, real-time monitoring and detecting the stability is high, can be used for qualitative, quantitative detection environment in the copper ion, to the cupric ion detection has very good application value. The reaction of the invention easy control of the condition, the operation is convenient, and the yield is high. (by machine translation)
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Paragraph 0014; 0036; 0041; 0043; 0049; 0053; 0055
(2019/04/17)
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- Synthesis of novel indole derivatives containing double 1,3,4-oxadiazole moiety as efficient bactericides against phytopathogenic bacterium Xanthomonas oryzae
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Abstract: A series of novel indole derivatives containing double 1,3,4-oxadiazole moiety was designed, synthesized and evaluated for their antibacterial activities in vitro. These compounds were fully characterized by 1H NMR, 13C NMR, and HRMS. Bioassay results indicated that most of title compounds exhibited excellent antibacterial activities against rice bacterial pathogen Xanthomonas oryzae (Xoo). For example, compounds 7d, 7h, 7i, 7j, 7k, 7l and 7m had the half-maximal effective concentration (EC50) values of 52.31, 54.12, 40.65, 38.80, 51.13, 52.75 and 50.66?μg/mL, respectively, which was better than that of commercial product bismerthiazol (BMT) (85.18?μg/mL). The experimental results proved that indole derivatives bearing double 1,3,4-oxadiazole unit are promising candidates for the development of new agricultural bactericides against pathogenic bacterium Xoo. Graphical abstract: [Figure not available: see fulltext.].
- Tian, Kun,Li, Xiao-Qin,Zhang, Li,Gan, Yi-Yuan,Meng, Jiao,Wu, Shou-Qun,Wan, Jin-Lin,Xu, Yang,Cai, Chao-Ting,Ouyang, Gui-Ping,Wang, Zhen-Chao
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- Towards a sustainable synthesis of amides: chemoselective palladium-catalysed aminocarbonylation of aryl iodides in deep eutectic solvents
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A palladium-catalysed aminocarbonylation of (hetero)aryl iodides has, for the first time, been accomplished in deep eutectic solvents as environmentally benign and recyclable media, under mild conditions. The reactions proceeded with a good substrate scope, and a variety of amides have been synthesized in yields up to 98%.
- Messa, Francesco,Perrone, Serena,Capua, Martina,Tolomeo, Francesco,Troisi, Luigino,Capriati, Vito,Salomone, Antonio
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p. 8100 - 8103
(2018/07/29)
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- Unprecedented alkylation of carboxylic acids by boron trifluoride etherate
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The alkylation of carboxylic acids by an ethyl moiety of boron trifluoride etherate in the absence of ethyl alcohol from the reaction system is unexpected and novel. Both aromatic and aliphatic carboxylic acids were clearly alkylated affording good yields in short reaction times with the exception of nicotinic acid that necessitated an overnight reaction. It was noted that while ortho-substituted hydroxyl groups of carboxylic acids investigated were not affected by alkylation, those of meta- and para-substituted carboxylic acids were partially etherified. Furthermore, the alkylation reaction was found to be compatible with a range of functional groups such as halogens, amino and nitro groups except for the alkene function of undecylenic acid that underwent polymerisation with concomitant alkylation of its carboxylic acid function.
- Jumbam, Ndze D.,Maganga, Yamkela,Masamba, Wayiza,Mbunye, Nomthandazo I.,Mgoqi, Esethu,Mtwa, Sphumusa
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p. 387 - 392
(2018/09/06)
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- Method for preparing aminopyridine from methylpyridine, and purifying method of aminopyridine
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The invention relates to the field of organic synthesis, and concretely relates to a method for preparing aminopyridine from methylpyridine, and a purifying method of aminopyridine. Crude aminopyridine is prepared from corresponding methylpyridine through oxidation, esterification, hydrazinolysis and rearrangement reactions, the reaction yield of every step is high, and a post-treatment technology is easy to industrially operate; in the oxidation reaction, beta-cyclodextrin is used as a catalyst, so the conversion rate of the oxidation reaction is increased, and the generation of byproducts is reduced; and anhydrous ethanol and an alkane reagent are used to re-crystallize the crude aminopyridine, and a decolorizing agent is combined, and the purity of the final product reaches 98% or more; and the purifying method has the advantages of simplicity, easiness in operation, easily available raw materials, and suitableness for industrial production.
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- Preparation method of ethyl nicotinate
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The invention relates to a preparation method of ethyl nicotinate. The preparation method is characterized by comprising the following steps of: adding nicotinic acid, absolute ethyl alcohol and an esterification reaction solid acid catalyst into methylbenzene; stirring the mixture to react for 3-6h at 50-65 DEG C; then raising the temperature to return and divide water; finishing the reaction till no water is divided; reducing the temperature to room temperature; filtering and recovering the esterification reaction solid acid catalyst; recovering methylbenzene at a reduced pressure from the filtrate; recovering the methylbenzene to obtain a light yellow transparent liquid which is the finished product ethyl nicotinate, wherein the molar ratio of nicotinic acid and absolute ethyl alcohol is 1: 1 to 1: 2; the weight ratio of nicotinic acid and methylbenzene is 1:0.3 to 1:8; the adding amount of the esterification reaction solid acid catalyst is 0.01-0.1 time of the weight of the nicotinic acid; the esterification reaction solid acid catalyst is an HND230 solid catalyst. The preparation method provided by the invention has the advantages of reducing generation of highly polluted wastewater, reducing the manual and equipment costs and being relatively suitable for industrial production on a large scale.
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Paragraph 0007; 0008; 0009; 0010
(2017/08/31)
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- Design, synthesis and biological evaluation of aminobenzyloxyarylamide derivatives as selective κ opioid receptor antagonists
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Opioid receptors play an important role in both behavioral and mood functions. Based on the structural modification of LY2456302, a series of aminobenzyloxyarylamide derivatives were designed and synthesized as κ opioid receptor antagonists. The κ opioid receptor binding ability of these compounds were evaluated with opioid receptors binding assays. Compounds 1a-d showed high affinity for κ opioid receptor. Especially for compound 1c, exhibited a significant Kivalue of 15.7?nM for κ opioid receptor binding and a higher selectivity over μ and δ opioid receptors compared to (±)LY2456302. In addition, compound 1c also showed potent κ antagonist activity with κ IC50?=?9.32?nM in [35S]GTP-γ-S functional assay. The potential use of the representative compounds as antidepressants was also investigated. The most potent compound 1c not only exhibited potent antidepressant activity in the mice forced swimming test, but also displayed the effect of anti-anxiety in the elevated plus-maze test.
- Wang, Junwei,Song, Qiao,Xu, Anhua,Bao, Yu,Xu, Yungen,Zhu, Qihua
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- 7-substituted-4-aryl coumarins compound, and preparation method and application thereof
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The invention discloses a 7-substituted-4-aryl coumarins compound, and a preparation method and an application thereof and belongs to the technical field of antitumor drugs. The 7-substituted-4-aryl coumarins compound is acquired in the manner of modifying and remolding 4 and 7 loci of the coumarins. The structural formula is shown in the specification. A pharmacological experiment proves that such a compound has an excellent antitumor activity, can be used for preparing the antitumor drugs, is capable of supplying a new selection for the development and application of the antitumor drugs and further can be applied to the design and optimization of the antitumor drugs. The preparation method of the compound has the advantages of easily acquired raw materials, mild reaction condition, easily realized synthesis method, simple reaction process and operation, low-cost reagents and higher yield.
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Paragraph 0127; 0128
(2017/08/02)
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- Synthesis, spectral analysis and antibacterial evaluation of 5-substituted-1,3,4-oxadiazol-2-yl 4-(4-methylpiperidin-1-ylsulfonyl)benzyl sulfides
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Owing to valuable biological activities of 1,3,4-oxadiazole, sulfamoyl and piperidine functionalities, some new 1-(4-{[(5-substituted-1,3,4-oxadiazol-2-yl) thio]methyl}benzene sulfonyl)-4-methylpiperidine (6a-o) derivatives have been introduced. The target molecules were synthesized from different aralkyl/aryl carboxylic acids, 1a-o, through a series of steps. First the compounds, 1a-o, were converted to heterocyclic 1,3,4-oxadiazole nucleophiles, 4a-o. Second an electrophile as 1-(4-bromomethylbenzenesulfonyl)-4-methylpiperidine (5) was synthesized from 4-methylpiperidine. Finally the target compounds, 6a-o, were prepared by reacting 4a-o with 5 in DMF and LiH. The final compounds were structurally elucidated by spectral data of IR, 1H-NMR and EI-MS. All the compounds were screened for their antibacterial evaluation and found to exhibit valuable results.
- Aziz-Ur-Rehman,Ahtzaz, Samreen,Abbasi, Muhammad Athar,Siddiqui, Sabahat Zahra,Rasool, Shahid,Ahmad, Irshad
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p. 3370 - 3375
(2017/05/22)
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- Diethyloxalate as “CO” Source for Palladium-Catalyzed Ethoxycarbonylation of Bromo- and Chloroarene Derivatives
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Palladium(II)-catalyzed ethoxycarbonylation of aryl bromides with diethyloxalate oxalate is described. Functionalized aromatic esters can be efficiently synthesized with only 0.65 mol % PdCl2(PPh3)2 catalyst under microwav
- Monrose, Amandine,Salembier, Helori,Bousquet, Till,Pellegrini, Sylvain,Pélinski, Lydie
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supporting information
p. 2699 - 2704
(2017/08/16)
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- Room Temperature Carbonylation of (Hetero) Aryl Pentafluorobenzenesulfonates and Triflates using Palladium-Cobalt Bimetallic Catalyst: Dual Role of Cobalt Carbonyl
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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.).
- Joseph, Jayan T.,Sajith, Ayyiliath M.,Ningegowda, Revanna C.,Shashikanth, Sheena
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supporting information
p. 419 - 425
(2017/02/10)
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- Silver-catalyzed chemoselective annulation of propargyl amines with alkynes for access to pyridines and pyrroles
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The annulation of propargyl amines with electron-deficient alkynes in the presence of silver salts affording pyridines and pyrroles has been developed. The chemoselective [4+2] or [3+2] annulation approach to pyridines or pyrroles depends on the structure
- Nizami, Tauqir A.,Hua, Ruimao
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p. 6080 - 6084
(2017/09/23)
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- Iodobenzene Dichloride in the Esterification and Amidation of Carboxylic Acids: In-Situ Synthesis of Ph3PCl2
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A novel, in-situ synthesis of dichlorotriphenylphosphorane (Ph3PCl2) is accomplished upon combining PPh3and the easily prepared hypervalent iodine reagent iodobenzene dichloride (PhICl2). The phosphorane is selectively generated in the presence of carboxylic acid or alcohol residues to rapidly produce acyl chlorides and alkyl chlorides in high yields. Addition of EtOH, PhOH, BnOH, Et2NH or CH2N2results in the direct synthesis of esters, amides and diazo ketones from carboxylic acids.
- Carle, Myriam S.,Shimokura, Grace K.,Murphy, Graham K.
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p. 3930 - 3933
(2016/08/24)
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- Synthesis and biological activities of novel 5-substituted-1,3,4-oxadiazole Mannich bases and bis-Mannich bases as ketol-acid reductoisomerase inhibitors
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A series of novel 5-substituted-1,3,4-oxadiazole Mannich bases and bis-Mannich bases have been conveniently synthesized in good yields. Their structures were characterized by IR,1H NMR,13C NMR and elemental analysis. The preliminary bioassay results indicated that some of the compounds showed promising in vitro fungicidal activities towards several test plant fungi; some of them exhibited significant herbicidal activities against Brassica campestris and excellent in vitro inhibitory activities against rice ketol-acid reductoisomerase (KARI). Among 14 novel compounds, 8c, 8d and 8m showed potent KARI inhibitory activities with Kivalue of (0.96?±?0.42), (3.86?±?0.49) and (3.10?±?0.71) μmol/L, respectively, and were comparable with IpOHA. These compounds could be novel KARI inhibitors for further investigation. The density functional theory (DFT) calculations and molecular docking were carried out to study the structure–activity relationship (SAR) of the active inhibitors in this Letter.
- Zhang, Yan,Liu, Xing-Hai,Zhan, Yi-Zhou,Zhang, Li-Yuan,Li, Zheng-Ming,Li, Yong-Hong,Zhang, Xiao,Wang, Bao-Lei
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p. 4661 - 4665
(2016/09/13)
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- Organocatalytic Synthesis of Fused Bicyclic 2,3-Dihydro-1,3,4-oxadiazoles through an Intramolecular Cascade Cyclization
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Hydrazone-carboxylic acids undergo intramolecular cyclization in the presence of pivaloyl chloride, iPr2NEt, and catalytic DABCO to form a range of substituted fused tricyclic 2,3-dihydro-1,3,4-oxadiazoles in high yields.
- Fugard, Alison J.,Thompson, Bethany K.,Slawin, Alexandra M. Z.,Taylor, James E.,Smith, Andrew D.
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supporting information
p. 5824 - 5827
(2015/12/11)
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- Potent antimicrobial agents against azole-resistant fungi based on pyridinohydrazide and hydrazomethylpyridine structural motifs
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Abstract Schiff base derivatives have recently been shown to possess antimicrobial activity, and these derivatives include a limited number of salicylaldehyde hydrazones. To further explore this structure-activity relationship between salicylaldehyde hydrazones and antifungal activity, we previously synthesized and analyzed a large series of salicylaldehyde and formylpyridinetrione hydrazones for their ability to inhibit fungal growth of both azole-susceptible and azole-resistant species of Candida. While many of these analogs showed excellent growth inhibition with low mammalian cell toxicity, their activity did not extend to azole-resistant species of Candida. To further dissect the structural features necessary to inhibit azole-resistant fungal species, we synthesized a new class of modified salicylaldehyde derivatives and subsequently identified a series of modified pyridine-based hydrazones that had potent fungicidal antifungal activity against multiple Candida spp. Here we would like to present our synthetic procedures as well as the results from fungal growth inhibition assays, mammalian cell toxicity assays, time-kill assays and synergy studies of these novel pyridine-based hydrazones on both azole-susceptible and azole-resistant fungal species.
- Backes, Gregory L.,Jursic, Branko S.,Neumann, Donna M.
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p. 3397 - 3407
(2015/08/03)
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- Synthesis of some 1,2,4-triazoles as potential anti-tubercular agents
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A series of 5-(N-substituted carboxamidoethylthio)-3-(3'pyridyl)-4- amino-1,2,4-triazole derivatives 6a-j have been synthesized and evaluated for anti-tubercular activity. They are screened in-vitro at 10μg/mL concentration against Mycobacterium tuberculosis H37RV (ATCC 27294). All the compounds are showing antitubercular activity when compared with the standard drug Amikacin. Compounds 6e and 6h are found active as they displayed IC50 and IC90 values at 100μg/mL.
- Vijayaraghavan,Shirodkar
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p. 1149 - 1153
(2015/09/28)
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- Chemistry and antioxidant properties of titanium(IV) complexes
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Abstract The synthesis of titanium(IV) complexes with biologically active hydrazide ligands has been carried out. The complexes were characterized by spectroscopic methods (IR, 1H NMR and 13C NMR), elemental analysis and conductivity studies. These studies suggest bidentate coordination of the ligands through carbonyl oxygen and primary amine nitrogen, resulting in octahedral geometries. Hydrazides with pyridyl substituents displayed 1:2 metal-to-ligand ratio, and hydrazides with imino substituents exhibited 1:3 metal-to-ligand ratio resulting in an outer sphere complex. The remaining complexes displayed inner sphere coordination with 1:1 metal-to-ligand ratio. These complexes exhibit varying degrees of radical scavenging properties against DPPH, superoxide and nitric oxide free radicals. The free ligands showed inhibition against DPPH but were inactive against superoxide and nitric oxide free radicals. The structure-activity relationships of the complexes are discussed.
- Shaikh, Zara,Ashiq, Uzma,Jamal, Rifat Ara,Mahroof-Tahir, Mohammad,Shamshad, Bushra,Sultan, Sadaf
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p. 665 - 671
(2015/08/06)
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- Palladium-Catalyzed Carbonylations of Arylboronic Acids: Synthesis of Arylcarboxylic Acid Ethyl Esters
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An approach for the palladium-catalyzed ethoxycarbonylations of arylboronic acids using diethyl pyrocarbonate as carbon monoxide/carbon dioxide (CO/CO2) surrogate in moderate to good yields has been investigated.
- Liang, Apeng,Han, Shuaijun,Wang, Liang,Li, Jingya,Zou, Dapeng,Wu, Yangjie,Wu, Yusheng
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supporting information
p. 3104 - 3108
(2015/11/03)
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- Palladium supported on triphenylphosphine functionalized porous organic polymer: A highly active and recyclable catalyst for alkoxycarbonylation of aryl iodides
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An efficient method for the alkoxycarbonylation of aryl iodides using palladium supported on triphenylphosphine functionalized porous organic polymer (Pd@KAPs(Ph-PPh3)) as the catalyst is reported. Under balloon pressure of CO, various aryl iodides on carbonylation with alcohols and phenols give the corresponding products in moderate to excellent yields (74-96%). The catalyst can be easily separated by simple filtration process and recycled up to ten times without significant decrease in activity. The salient features of this protocol are the simplicity in handling of the catalyst, low CO pressure, negligible palladium leaching and good catalyst recyclability.
- Lei, Yizhu,Wu, Linjuan,Zhang, Xuefeng,Mei, Hui,Gu, Yanlong,Li, Guangxing
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p. 164 - 169
(2015/02/19)
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- Bis azide-triphenylphosphine as a reagent for esterification at room temperature
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Modified Staudinger reaction is a well-established reaction for the amide synthesis from organic azides and carboxylic acids in the presence of phosphorous reagents. In contrary to this, it is notable that bis azide in the presence of triethylphosphite or trimethylphosphite does not afford the expected bis amides but affords the ethyl or methyl esters of the carboxylic acids respectively. This serendipitous observation when further investigated results in the discovery of bis azide-triphenylphosphine as an efficient reagent for esterification at room temperature.
- Dinesh, Murugan,Archana, Sivasubramaniyan,Ranganathan, Raja,Sathishkumar, Murugan,Ponnuswamy, Alagusundaram
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supporting information
p. 6975 - 6979
(2015/11/27)
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- Design, synthesis, molecular docking and 3D-QSAR studies of potent inhibitors of enoyl-acyl carrier protein reductase as potential antimycobacterial agents
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In order to develop a lead antimycobacterium tuberculosis compound, a series of 52, novel pyrrole hydrazine derivatives have been synthesized and screened which target the essential enoyl-ACP reductase. The binding mode of the compounds at the active site of enoyl-ACP reductase was explored using surflex-docking method. The binding model suggests one or two hydrogen bonding interactions between pyrrole hydrazones and InhA enzyme. Highly active compound 5r (MIC 0.2 μg/mL) showed hydrogen bonding interactions with Tyr158 and NAD+ in the same manner as those of ligands PT70 and triclosan. The CoMFA and CoMSIA models generated with database alignment were the best in terms of overall statistics. The predictive ability of the CoMFA and CoMSIA models was determined using a test set of 13 compounds, which gave predictive correlation coefficients (rpred2) of 0.896 and 0.930, respectively.
- More, Uttam A.,Joshi, Shrinivas D.,Aminabhavi, Tejraj M.,Gadad, Andanappa K.,Nadagouda, Mallikarjuna N.,Kulkarni, Venkatrao H.
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p. 199 - 218
(2014/01/06)
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- PROCESS FOR PREPARING RACEMIC NICOTINE
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Provided is a process for preparing racemic nicotine from 1-methyl-3-nicotinoyl-2-pyrrolidone or a salt thereof using one-pot process. The process comprises the following steps: 1) in a reaction vessel, reacting 1-methyl-3-nicotinoyl-2-pyrrolidone or a salt thereof in the presence of a suitable solvent and a strong acid by heat; after the reaction is complete, cooling the same and adjusting the pH to 7-8 with alkali; and 2) directly adding a reductant into the above vessel, and after the reaction, purifying the product so as to obtain high purity racemic nicotine or a salt thereof.
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Paragraph 0045; 0046
(2014/02/16)
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- Regioselective quadruple domino aldolization/aldol condensation/Michael/ SNAr-cyclization: Construction of hexacyclic indeno-fused C-nor-D-homo-steroid frameworks
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An operationally simple and highly atom-economic anionic quadruple domino reaction sequence for the synthesis of hexacyclic indeno-fused naphthalene/quinoline molecules having structural resemblance with the C-nor-D-homo-steroid nucleus has been developed. Promoter and solvent specificity, regioselectivity and mechanistic details were experimentally established. Catalyst concentration and solvent dependent switching of domino steps creating four new C-C bonds are discussed.
- Chanda, Tanmoy,Chowdhury, Sushobhan,Ramulu, B. Janaki,Koley, Suvajit,Jones, Raymond C.F.,Singh, Maya Shankar
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supporting information
p. 2190 - 2194
(2014/03/21)
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- Synthesis, biologicalevaluation, and molecular modeling of (E)-2-aryl-5-styryl-1,3,4-oxadiazolederivatives as acetylcholine esterase inhibitors
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A library of 2,5-disubstituted 1,3,4-oxadiazole derivatives of (E)-2-aryl-5-(3,4,5-trimethoxystyryl)-1,3,4-oxadiazoles 4(a-o) and (E)-2-aryl-5-(2-benzo[d][1,3]dioxol-5-yl)vinyl)-1,3,4-oxadiazoles 5(a-q) were synthesized and evaluated for their in vitro acetylcholinesterase (AChE) inhibitory activity. All the synthesized compounds exhibited moderate to good inhibitory activity toward the AChE enzyme. Among the oxadiazole derivatives examined, compounds 4a, 4g, 5c, and 5m (IC50 values of 24.89, 13.72, 37.65, and 19.63 μM, respectively) were found to be promising inhibitors of AChE. Molecular protein-ligand docking studies were examined for these compounds using GOLD docking software and their binding conformations were determined and the simultaneous interactions mode was also established for the potent derivatives. Springer Science+Business Media 2013.
- Kamal, Ahmed,Shaik, Anver Basha,Reddy, G. Narender,Kumar, C. Ganesh,Joseph, Joveeta,Kumar, G. Bharath,Purushotham, Uppula,Sastry, G. Narahari
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p. 2080 - 2092
(2014/05/06)
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- Novel arylhydrazone derivatives bearing a rhodanine moiety: Synthesis and evaluation of their antibacterial activities
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A series of arylhydrazone derivatives bearing a rhodanine moiety have been synthesized, characterized, and evaluated as antibacterial agents. Some of these compounds showed potent antibacterial activities against several different strains of Gram-positive bacteria, including multidrug-resistant clinical isolates. Of the compounds tested, IIk and IIIk were identified as the most effective, with minimum inhibitory concentration values of 2-4 μg/mL against multidrug-resistant Gram-positive organisms, including methicillin-resistant and quinolone-resistant Staphylococcus aureus. None of the compounds exhibited any activity against the Gram-negative bacteria Escherichia coli 1356 at 64 μg/mL.
- Li, Wei,Zheng, Chang-Ji,Sun, Liang-Peng,Song, Ming-Xia,Wu, Yan,Li, Yin-Jing,Liu, Yi,Piao, Hu-Ri
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p. 852 - 861
(2014/08/05)
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- Expedient carbonylation of aryl halides in aqueous or neat condition
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An expedient and versatile, microwave-assisted procedure for the carbonylation of aryl halides with boronic acids, alcohols or amines in water or under neat conditions has been developed. The reaction is catalyzed by fluorous, oxime-based palladacycle 1 that shows an excellent recyclable property and low levels of Pd leaching. To demonstrate the usefulness of the protocol, we applied it to the preparation of compounds of pharmaceutical interest, including a precursor of the reverse transcriptase inhibitor, niacin, benzocaine and butamben.
- Ang, Wei Jie,Lo, Lee-Chiang,Lam, Yulin
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p. 8545 - 8558
(2014/12/11)
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- Kinetic study on nucleophilic substitution reaction of 5-nitro-8-quinolyl benzoate, picolinate, nicotinate and isonicotinate with alkali metal ethoxide: Effect of nonleaving group on reactivity and transition state structure
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Pseudo-first-order rate constants (kobsd) have been measured spectrophotometrically for the reactions of 5-nitro-8-quinolyl nicotinate (4) and 5-nitro-8-quinolyl isonicotinate (5) with alkali metal ethoxides (EtOM; M = K, Na and Li) in anhydrous ethanol at 25.0 ± 0.1 °C. The plots of kobsd vs. [EtOM] curve slightly upward for the reactions with EtOK and EtONa but are linear for the reactions with EtOLi and for those with EtOK in the presence of 18-crown-6-ether. Dissection of kobsd into k EtO- and kEtOM (i.e., the second-order rate constants for the reactions with the dissociated EtO- and ion-paired EtOM, respectively) has revealed that the reactivity increases in the order EtO - ≈ EtOLi - EtOK EtONa for the reactions of 5. Comparison of the kinetic results for the reactions of 4 and 5 with those reported previously for the corresponding reactions of 5-nitro-8-quinolyl benzoate (2) and picolinate (3) has revealed that the esters possessing a pyridine ring (i.e., 3-5) are significantly more reactive than the benzoate ester 2 due to the presence of the electronegative N atom (e.g., 2 ? 3 4 5). It has been concluded that M+ ion catalyzes the reactions of 3-5 by increasing the electrophilicity of the reaction center through a five-membered cyclic transition state (TS) for the reaction of 3 and via a four-membered cyclic TS for the reactions of 4 and 5.
- Lee, Jieun,Kim, Min-Young,Um, Ik-Hwan
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p. 1789 - 1793
(2014/07/07)
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- Transformation of amides into esters by the use of chlorotrimethylsilane
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A mild transformation of various amides and imides into the corresponding esters and diesters in good yields by using chlorotrimethylsilane and alcohols at rt are described. Either primary, secondary, or tertiary amide or imide can be used in this transformation. Primary and secondary alcohols gave better yields than tertiary alcohols.
- Xue, Cuihua,Luo, Fen-Tair
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p. 359 - 362
(2015/02/02)
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- Polymer supported Pd catalyzed carbonylation of aryl bromides for the synthesis of aryl esters and amides
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A polymer-anchored palladium(ii) catalyst was synthesized and characterized using various spectroscopic techniques. Its catalytic activity was evaluated for the alkoxycarbonylation and aminocarbonylation reactions. These carbonylation reactions were carried out for various substituted aryl bromides using alcohols and amines. Both the reactions were optimized by varying the bases, temperature and solvents. These experiments were carried out under high CO pressure. The catalyst was very stable and can be facilely recovered and reused six times without a significant decrease in its activity and selectivity. the Partner Organisations 2014.
- Islam, Sk Manirul,Ghosh, Kajari,Roy, Anupam Singha,Molla, Rostam Ali
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p. 38986 - 38999
(2014/11/07)
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- Highly selective trifluoroacetic ester/ketone metathesis: An efficient approach to trifluoromethyl ketones and esters
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A highly selective and atom efficient 'trifluoroacetic ester/ketone metathesis' has been sincerely witnessed. Enolizable alkyl (at least two non-hydrogen atoms) aryl ketones were found to react readily with ethyl trifluoroacetate under the promotion of NaH to afford trifluoroacetic ester/ketone exchange products, trifluoromethyl ketones (TFMKs), and aromatic acid esters, which were quite different from the general Claisen condensation products, 1,3-diketones. The outcome of the reaction between ketone and ethyl trifluoroacetate is strongly related to the structures of substrates, the steric congestion caused by alkyl group is in favor of the C-C bond cleavage. DFT investigation further disclosed that the metathesis reaction was a kinetically favored pathway. Using only a slight excess of cheap trifluoromethylation reagent, simple operation and mild conditions make it a practical method for preparation of TFMKs on large scale, as well as a new choice of converting aryl alkyl ketones to aromatic acid esters.
- Zhou, Yuhan,Yang, Dongmei,Luo, Gen,Zhao, Yilong,Luo, Yi,Xue, Na,Qu, Jingping
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p. 4668 - 4674
(2014/06/23)
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- Synthesis, biological evaluation and QSAR study of a series of substituted quinazolines as antimicrobial agents
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A novel series of 1-N-substituted-3-(4-(5-(pyridin-3-yl)-1,3,4-oxadiazol-2- ylthio)quinazolin-6-yl)urea/thiourea derivatives (6a-6r) and 1-N-substituted-3-(7-(4-methylpiperazin-1-yl)-4-(5-(pyridin-3-yl)-1,3, 4-oxadiazol-2-ylthio)quinazolin-6-yl)urea/thiourea derivatives (14a-14s) were synthesized and screened for antimicrobial activity against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, and Escherichia coli. Biological results indicated that the synthesized compounds showed a broad-spectrum activity against tested microorganisms at MIC values between 6.25 and 100 μg/mL. Compound 6r showed a broad spectrum of activity and was found to be active against all tested species. A quantitative structure-activity relationship study has been carried out on the synthesized compounds to get better insights into pharmacophoric features responsible for the antibacterial activity. Genetic function approximation technique was used to identify descriptors that influence biological activity. Hydrophobic (AlogP98), electronic (atomic polarizability), and topological (radius of gyration) descriptors were found to affect the activity significantly. Generated model was found to be statistically significant (r 2 = 0.86, predictive index = 0.96) and predictive as indicated by very low residuals in internal and external cross-validation.
- Buha, Vipul M.,Rana, Dharmaraj N.,Chhabria, Mahesh T.,Chikhalia, Kishor H.,Mahajan, Bhushan M.,Brahmkshatriya, Pathik S.,Shah, Nisha K.
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p. 4096 - 4109
(2013/09/02)
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- Novel 1,3,4-oxadiazole thioether derivatives targeting thymidylate synthase as dual anticancer/antimicrobial agents
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A series of novel 1,3,4-oxadiazole thioether derivatives (compounds 9-44) were designed and synthesized as potential inhibitors of thymidylate synthase (TS) and as anticancer agents. The in vitro anticancer activities of these compounds were evaluated against three cancer cell lines by the MTT method. Among all the designed compounds, compound 18 bearing a nitro substituent exhibited more potent in vitro anticancer activities with IC50 values of 0.7 ± 0.2, 30.0 ± 1.2, 18.3 ± 1.4 μM, respectively, which was superior to the positive control. In the further study, it was identified as the most potent inhibitor against two kinds of TS protein (for human TS and Escherichia coli TS, IC50 values: 0.62 and 0.47 μM, respectively) in the TS inhibition assay in vitro and the most potent antibacterial agents with MIC (minimum inhibitory concentrations) of 1.56-3.13 μg/mL against the tested four bacterial strains. Molecular docking and 3D-QSAR study supported that compound 18 can be selected as dual antitumor/antibacterial candidate in the future study.
- Du, Qian-Ru,Li, Dong-Dong,Pi, Ya-Zhou,Li, Jing-Ran,Sun, Jian,Fang, Fei,Zhong, Wei-Qing,Gong, Hai-Bin,Zhu, Hai-Liang
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p. 2286 - 2297
(2013/05/09)
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- Cobalt carbonyl as an effective CO source in one-pot synthesis of esters from aryl halides
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For the first time, we have successfully applied Co2(CO) 8 as an effective carbonyl source for the Pd catalysed alkoxycarbonylation of aryl halides affording the corresponding aryl esters under mild microwave conditions. A wide variety of esters and carbonyl derivatives were prepared using this protocol.
- Baburajan,Senthilkumaran,Elango, Kuppanagounder P.
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p. 3050 - 3056
(2013/10/01)
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- Selective oxidation of alcohols to esters using heterogeneous Co 3O4-N@C catalysts under mild conditions
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Novel cobalt-based heterogeneous catalysts have been developed for the direct oxidative esterification of alcohols using molecular oxygen as benign oxidant. Pyrolysis of nitrogen-ligated cobalt(II) acetate supported on commercial carbon transforms typical homogeneous complexes to highly active and selective heterogeneous Co3O4-N@C materials. By applying these catalysts in the presence of oxygen, the cross and self-esterification of alcohols to esters proceeds in good to excellent yields.
- Jagadeesh, Rajenahally V.,Junge, Henrik,Pohl, Marga-Martina,Radnik, Joerg,Brueckner, Angelika,Beller, Matthias
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supporting information
p. 10776 - 10782
(2013/08/23)
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- The dual role of ionic liquid BmimBF4, precursor of N-heterocyclic carbene and solvent, in the oxidative esterification of aldehydes
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Room temperature ionic liquid BmimBF4 (1-butyl-3- methylimidazolium tetrafluoroborate) has been utilized in the N-heterocyclic carbene-catalyzed oxidation of aldehydes to yield esters. In the presence of MnO2 as oxidant and of DBU and caesium carbonate as bases, aromatic, heteroaromatic and aliphatic esters have been isolated in good to excellent yields. The recyclability of the used ionic liquid along with the excess of inorganic reagents has been proved. The simple and cheap BmimBF4 ionic liquid played the dual role of precatalyst and solvent. This is the first time that such a reaction has been carried out with an ionic liquid as solvent.
- Chiarotto, Isabella,Feroci, Marta,Sotgiu, Giovanni,Inesi, Achille
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p. 8088 - 8095
(2013/08/23)
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- Transition metal-free direct C-H bond thiolation of 1,3,4-oxadiazoles and related heteroarenes
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A convenient transition metal-free procedure for the direct thiolation of 1,3,4-oxadiazole C-H bonds using diaryl disulfides has been developed. Other substrates including indole, benzothiazole, N-phenylbenzimidazole, and caffeine were also thiolated in this manner, providing the corresponding products in good to excellent yields. This journal is
- Zou, Liang-Hua,Reball, Jens,Mottweiler, Jakob,Bolm, Carsten
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supporting information
p. 11307 - 11309,3
(2020/10/15)
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- Synthesis, antimycobacterial, antiviral, antimicrobial activities, and QSAR studies of nicotinic acid benzylidene hydrazide derivatives
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A series of nicotinic acid benzylidene hydrazide derivatives (1-18) was synthesized and tested in vitro for biological evaluations. The antimycobacterial activity results indicated that the presence of electron-withdrawing halogen groups at para position of the phenyl ring improved their activity. The results of antiviral evaluation depicted that none of the synthesized derivatives inhibited the replication of viruses at subtoxic concentration. Further, the antimicrobial screening results indicated that compounds having OCH3 and NO2 substituents were the most active ones. QSAR investigations revealed that multitarget QSAR models were effective in describing the antimicrobial activity. Springer Science+Business Media, LLC 2011.
- Narang, Rakesh,Narasimhan, Balasubramanian,Sharma, Sunil,Sriram, Dharmarajan,Yogeeswari, Perumal,De Clercq, Erik,Pannecouque, Christophe,Balzarini, Jan
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p. 1557 - 1576
(2012/11/07)
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- Ligand free palladium catalyzed decarboxylative cross-coupling of aryl halides with oxalate monoester salts
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Ligand free Pd-catalyzed decarboxylative cross-coupling of potassium oxalate monoester and derivatives with aryl iodides and bromides is described. Functionalized aromatic esters can be efficiently synthesized via this method with only 1.0 mol % Pd(OAc)2 catalyst without any phosphine ligand. This method illustrates an inexpensive and operationally simple method for the preparation of aromatic esters and acids, which is especially beneficial for a large scale synthesis.
- Li, Yan,Chen, Huan-Huan,Wang, Chu-Fei,Xu, Xiao-Lan,Feng, Yi-Si
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p. 5796 - 5799
(2012/10/29)
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- Nicotinic acid benzylidene/phenyl-ethylidene hydrazides: Synthesis, antimicrobial evaluation and QSAR studies
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A series of nicotinic acid hydrazides (1-19) was synthesized and tested in vitro for antimycobacterial, antiviral, antibacterial and antifungal activities. The antimycobacterial activity results indicated that the presence of electron withdrawing halo groups improved the antimycobacterial activity. The antiviral evaluation showed that none of the synthesized derivatives inhibited the replication of viruses at subtoxic concentrations, except compounds 9 and 12. The antimicrobial screening results demonstrated that compounds having methoxy and 2-hydroxy naphthalene substituents were the most active ones against tested microbial strains. QSAR investigations revealed that multi-target QSAR models were found to be more effective in describing the antimicrobial activity than one-target QSAR models.
- Narang, Rakesh,Narasimhan, Balasubramanian,Sharma, Sunil,Sriram, Dharmarajan,Yogeeswari, Perumal,De Clercq, Erik,Pannecouque, Christophe,Balzarini, Jan
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experimental part
p. 733 - 749
(2012/05/05)
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- Metal ion catalysis and inhibition in nucleophilic substitution reactions of 4-nitrophenyl nicotinate and isonicotinate with alkali metal ethoxides in anhydrous ethanol
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A kinetic study is reported on nucleophilic substitution reactions of 4-nitrophenyl nicotinate 5 and isonicotinate 6 with alkali metal ethoxide EtOM (M = K, Na, and Li) in anhydrous ethanol at 25.0 ± 0.1 °C. Plots of pseudofirst- order rate constant kobsd vs. EtOM concentration exhibit upward curvature for the reactions of 5 and 6 with EtOK and EtONa but are almost linear for those with EtOLi. Dissection of kobsd into k EtO- and kEtOM (i.e., the second-order rate constant for the reaction with dissociated EtO- and ion-paired EtOM, respectively) has shown that kEtOK ≥ kEtONa > k EtO- but kEtOLi EtO -. It has been concluded that K+ and Na+ ions catalyze the reactions by increasing the electrophilicity of the carbonyl carbon atom through formation of a 4- embered cyclic transition state TS3 or TS4. However, M+ ion catalysis has been found to be much less significant for the reactions of 5 and 6 than for the corresponding reactions of 4-nitrophenyl picolinate 4, which was reported to proceed through a 5-membered cyclic transition state TS2. Although 5 and 6 are significantly more reactive than 4-nitrophenyl benzoate 3, the reactions of 5 and 6 result in smaller kEtOK/kEtO- ratios than those of 3. The electron-withdrawing ability of the nitrogen atom in the acyl moiety of 5 and 6 has been suggested to be responsible for the increase in reactivity and the decrease in the kEtOK/kEtO- ratio.
- Choi, Seo-Young,Hong, Yeon-Ju,Um, Ik-Hwan
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experimental part
p. 1951 - 1956
(2012/02/05)
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- Continuous-flow, palladium-catalysed alkoxycarbonylation reactions using a prototype reactor in which it is possible to load gas and heat simultaneously
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A prototype tube-in-tube reactor in which it is possible to load gas and heat simultaneously has been used in a continuous-flow approach to alkoxycarbonylation reactions of aryl iodides. In the stainless steel coil, liquid flows on the outside of a gas-permeable membrane. The coil can be heated and the temperature can be measured accurately via a probe touching the outer steel surface. A range of aryl iodides can be transformed to the corresponding esters in excellent conversion by reaction at 120 °C using 0.5 mol% palladium acetate as the catalyst with no additional ligand required. Small-scale optimization and substrate screening runs were followed by scale-up.
- Mercadante, Michael A.,Leadbeater, Nicholas E.
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experimental part
p. 6575 - 6578
(2011/11/05)
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- A continuous-flow approach to palladium-catalyzed alkoxycarbonylation reactions
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Using a continuous-flow approach, it is possible to perform alkoxycarbonylation reactions of aryl iodides. Optimized reactor design allows for adequate mixing of gaseous and liquid reagents. Reactions are performed at rates of around 3 mL/min and at concentrations of 1 M, allowing for significant volumes to be processed per unit time. Palladium acetate (0.5 mol %) is used as the catalyst without the need for an additional ligand.
- Kelly, Christopher B.,Lee, Christopher,Mercadante, Michael A.,Leadbeater, Nicholas E.
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experimental part
p. 717 - 720
(2011/12/01)
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