- Discovery of 7-alkyloxy- [1,2,4] triazolo[1,5-a] pyrimidine derivatives as selective positive modulators of GABAA1 and GABAA4 receptors with potent antiepileptic activity
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A series of 7-alkoxy - [1,2,4] triazolo [1, 5-a] pyrimidine derivatives were designed and synthesized. Maximal electroshock (MES) and pentylenetetrazole (PTZ) tests were utilized to access their anticonvulsant activity. Most of the series of compounds exhibited significant anti-seizure effects. Further studies demonstrated that the anticonvulsant activity of these compounds mainly depended on their allosteric potentiation of GABAA receptors. Among them, compound 10c was picked for the mechanism study due to its potent activity. The compound is more sensitive to subunit configurations of synaptic α1β2γ2 and extrasynaptic α4β3δ GABAA receptors, but there were no effects on NMDA receptors and Nav1.2 sodium channels. Meanwhile, 10c acted on the sites of GABAA receptors distinct from commonly used anticonvulsants benzodiazepines and barbiturates. Furthermore, studies from native neurons demonstrated that compound 10c also potentiated the activity of native GABAA receptors and reduced action potential firings in cultured cortical neurons. Such structural compounds may lay a foundation for further designing novel antiepileptic molecules.
- Wu, Jun,Hou, Zhipeng,Wang, Yan,Chen, Liping,Lian, Chengxi,Meng, Qingfei,Zhang, Chaoying,Li, Xiufen,Huang, Longjiang,Yu, Haibo
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- Cu-Catalyzed Synthesis of Benzoxazole with Phenol and Cyclic Oxime
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A Cu-catalyzed straightforward synthesis of benzoxazoles from free phenols and cyclic oxime esters is reported. The mild reaction conditions tolerate various electron-withdrawing and electron-donating functional groups on both substrates, affording benzoxazoles in moderate to good yields. With this protocol, large-scale syntheses of Ezutromid and Flunoxaprofe in one or two steps are demonstrated. A catalytic mechanism, which includes Cu-catalyzed amination via inner-sphere electron transfer and consequent annulation, is proposed.
- Wang, Zheng-Hai,Wang, Dong-Hui
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supporting information
p. 782 - 785
(2022/01/20)
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- Enantioselective decarboxylative Mannich reaction of β-keto acids withC-alkynylN-BocN,O-acetals: access to chiral β-keto propargylamines
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The chiral keto-substituted propargylamines are an essential class of multifunctional compounds in the field of organic and pharmaceutical synthesis and have attracted considerable attention, but the related synthetic approaches remain limited. Therefore, a concise and efficient method for the enantioselective synthesis of β-keto propargylaminesviachiral phosphoric acid-catalyzed asymmetric Mannich reaction between β-keto acids andC-alkynylN-BocN,O-acetals as easily availableC-alkynyl imine precursors has been demonstrated here, affording a broad scope of β-ketoN-Boc-propargylamines in high yields (up to 97%) with generally high enantioselectivities (up to 97?:?3 er).
- Chen, Li-Jun,Li, Wei,Shen, Bao-Chun,Sun, Zhong-Wen,Xie, Hui-Ding,Zhang, Cong-Cong
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supporting information
p. 8607 - 8612
(2021/10/20)
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- AZOLE DERIVATIVES, AND AGRICULTURAL AND HORTICULTURAL CHEMICALS AND INDUSTRIAL MATERIAL PROTECTING AGENTS
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To provide plant disease control agents that have low toxicity to humans and animals and excellent handling safety, and exhibit excellent control effect on a variety of plant diseases and high antibiotic action on plant disease germs.SOLUTION: An azole derivative according to the present invention is a compound represented by the formula (I) in the figure, or an N-oxide or agriculturally and pharmaceutically acceptable salt thereof.SELECTED DRAWING: None
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-
Paragraph 0119
(2021/02/13)
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- AMINOPYRIMIDINE DERIVATIVES AND THEIR USE AS ARYL HYDROCARBON RECEPTOR MODULATORS
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The present invention relates to novel compounds effective as modulators Aryl hydrocarbon receptor (AhR), pharmaceutical composition comprising the compounds for the modulation of AhR, or prevention or treatment of a disease, disorder, or condition associ
- -
-
Paragraph 1368; 1377-1380
(2021/10/02)
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- Discovery of [1,2,4]-triazolo [1,5-a]pyrimidine-7(4H)-one derivatives as positive modulators of GABAA1 receptor with potent anticonvulsant activity and low toxicity
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In searching for more effective and safer antiepileptic drugs, a series of 2,5-disubstituted [1,2,4]-triazolo[1,5-a]pyrimidine-7(4H)-one derivatives were designed and synthesized. Spontaneous Ca2+ oscillations (SCOs) of cortical neurons were used for in vitro phenotypic screening. Maximal electroshock test (MES) and pentylenetetrazole (PTZ) test were used to access their anticonvulsant activity, and rotarod test was used to estimate their neurotoxicity. The active compounds in in vitro model are specifically effective in pentylenetetrazole (PTZ)-induced epilepsy model but not maximal electroshock (MES) model, more importantly with lower neurotoxicity as compared to commonly used drugs. Among them, compound 5c and 5e showed significant anticonvulsant activities in PTZ-induced epilepsy model with ED50 values at 31.81 mg/kg and 40.95 mg/kg, respectively. These compounds have improved neurotoxicity with protective index (PI = TD50/ED50) values at 17.22 and 9.09, respectively. Finally we demonstrated that compound 5c and 5e mainly acted on GABAA receptor as positive modulators but not sodium channels. Thus the present study has provided potential candidates for further investigation in epilepsy.
- Huang, Longjiang,Ding, Jing,Li, Min,Hou, Zhipeng,Geng, Yanru,Li, Xiufen,Yu, Haibo
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- Cu-Mediated Expeditious Annulation of Alkyl 3-Aminoacrylates with Aryldiazonium Salts: Access to Alkyl N2-Aryl 1,2,3-Triazole-carboxylates for Druglike Molecular Synthesis
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Alkyl N-aryl 1,2,3-triazole-carboxylates are important molecules or intermediates in medicinal chemistry, but the synthesis of N2-aryl counterparts remains elusive. Herein, we describe a Cu-mediated annulation reaction of alkyl 3-aminoacrylates with aryldiazonium salts, both of which are readily available substrates. Furthermore, alkyl 2-aminoacrylates are also viable substrates. Diverse alkyl N2-aryl 1,2,3-triazole-carboxylates and their analogues can be rapidly prepared under mild conditions. Especially, this protocol allows one to access several druglike variants of carbonic anhydrase inhibitors and celecoxib.
- Liu, Hao-Nan,Cao, Hao-Qiang,Cheung, Chi Wai,Ma, Jun-An
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supporting information
p. 1396 - 1401
(2020/02/22)
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- An efficient route for the synthesis of N-(1H-benzo[d]imidazol-2-yl)benzamide derivatives promoted by CBr4 in one pot
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A metal-free one-pot method for the synthesis of N-(1H-benzo[d]imidazol-2-yl)benzamide derivatives was proposed mediated by CBr4. The reaction went through ring formation and opening processes with only two protons leaving and the thermodynamically favorable products were selectively formed in moderate to good yields.
- Li, Songhua,Li, Yunyi,Ma, Chen,Xie, Caixia
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- Chiral Vanadyl(V) Complexes Enable Efficient Asymmetric Reduction of β-Ketoamides: Application toward (S)-Duloxetine
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High-valent chiral oxidovanadium(V) complexes derived from 3,5-substituted-N-salicylidene-l-tert-leucine were used as catalysts in asymmetric reduction of N-benzyl-β-ketoamides. Among six different solvents, three different alcohol additives, and two different boranes examined, the use of pinacolborane in tetrahydrofuran (THF) with a t-BuOH additive led to the best results at -20 °C. The corresponding β-hydroxyamides can be furnished with yields up to 92percent and an enantiomeric excess (ee) up to 99percent. We have successfully extended this catalytic protocol for the synthesis of an (S)-duloxetine precursor.
- Chen, Chien-Tien,Maity, Nabin Ch.,Agarwal, Rachit,Lai, Chien-Fu,Liao, Yiya,Yu, Wei-Ru
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supporting information
p. 6408 - 6419
(2020/07/14)
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- General and selective syn -carboxylation-trifluoromethylation of terminal alkynes: Application to the late-stage modification of dehydrocholic acid
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A general and selective method is developed that allows difunctionalization of terminal alkynes by a Cu(iii)-CF3 complex and a carboxylic acid regioselectively and with unusual syn-stereochemistry. This method is broadly applicable to various carboxylic acids and terminal alkynes, producing a range of biologically active trifluoromethyl enol carboxylic esters. The synthetic potential of this method is further demonstrated by the late-stage functionalization of a complex pharmaceutical compound dehydrocholic acid.
- Zhang, Song-Lin,Xiao, Chang,Wan, Hai-Xing,Zhang, Xiaoming
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supporting information
p. 4099 - 4102
(2019/04/30)
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- Synthesis and in vitro anti-epileptic activities of novel [1,2,4]-triazolo[1,5-a]pyrimidin-7(4H)-one derivatives
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In this investigation, eight novel 2,5-disubstituted [1,2,4]-triazolo[1,5-a]pyrimidin-7(4H)-one and eight novel 2,5-disubstituted [1,2,4]-triazolo[1,5-a]pyrimidine amine derivatives were synthesized based on the novel marine natural product Essramycin. Their anti-epileptic activities were evaluated by 4-aminopyridine (4-AP)-induced hyper excitability model in primary cultured neocortical neurons. Five compounds with [1,2,4]-triazolo[1,5-a]pyrimidin-7(4H)-one skeleton showed remarkable anti-epileptic activities. The preliminary structure–activity relationship (SAR) showed that the pyrimidine-7(4H)-one motif is the necessary “active core” of anti-epileptic activity. To understand the action mechanism of anti-epileptic activity of [1,2,4]-triazolo[1,5-a]pyrimidin-7(4H)-one compounds, docking studies using the model of GABAA as docking scaffolds were performed and the docking results were in concordance with the experiment observations. (Figure presented.).
- Ding, Jing,Cao, Feng-De,Geng, Yan-Ru,Tian, Yuan,Li, Peng,Li, Xiu-Fen,Huang, Long-Jiang
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p. 1190 - 1204
(2019/01/05)
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- Iron-catalysed 1,2-acyl migration of tertiary α-azido ketones and 2-azido-1,3-dicarbonyl compounds
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Iron-catalysed 1,2-acyl migration of tertiary α-azido ketones and 2-azido-1,3-dicarbonyl compounds provides a simple and atom-economical approach toward enamides and isoquinolones. This paper reports two catalyst systems for these transformations which employ iron(ii) complexes [Fe(dpbz)]Br2 (dpbz = 1,2-bis(diphenylphosphino)benzene) and FeBr2/Et3N, respectively. [Fe(dpbz)]Br2 was found to be highly effective at converting 2-azido-2,3-dihydro-1H-inden-1-ones to isoquinolones. The reagent combination of FeBr2/Et3N, on the other hand, exhibited a broader catalytic scope, owing to the beneficial effect of Et3N. This latter catalyst system enables 2-azido-2-methyl-1,3-dicarbonyl compounds to be converted to the corresponding enamides under mild conditions in good yields.
- Yang, Tonghao,Lin, Yajun,Yang, Chaoqun,Yu, Wei
-
supporting information
p. 6097 - 6102
(2019/11/20)
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- PhIO/Et3N ? 3HF-Mediated Formation of Fluorinated 2H-Azirines via Domino Fluorination/Azirination Reaction of Enamines
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A variety of enamine carboxylic esters and enaminones were converted to the biologically interesting fluorinated 2H-azirines through reactions with PhIF2 generated in situ by PhIO and Et3N ? 3HF in 1,2-dichroloethane, which features the hypervalent iodine reagents-mediated introduction of fluorine atom and formation of the 2H-azirine skeleton under metal-free conditions. The domino reaction is postulated to proceed via a PhIF2-mediated oxidative fluorination and a subsequent azirination of the fluorinated enamine intermediates. (Figure presented.).
- Zhang, Yong,Zhao, Xiaoyuan,Zhuang, Chen,Wang, Senlin,Zhang-Negrerie, Daisy,Du, Yunfei
-
supporting information
p. 2107 - 2112
(2018/04/19)
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- Synthesis of trifluoromethylated 2H-azirines through Togni reagent-mediated trifluoromethylation followed by PhIO-mediated azirination
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The reaction of enamine compounds with the Togni reagent in the presence of CuI afforded β-trifluoromethylated enamine intermediates, which were converted directly to biologically interesting trifluoromethylated 2H-azirines by an iodosobenzene (PhIO)-mediated intramolecular azirination in a one-pot process.
- Sun, Jiyun,Zhen, Xiaohua,Ge, Huaibin,Zhang, Guangtao,An, Xuechan,Du, Yunfei
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supporting information
p. 1452 - 1458
(2018/07/05)
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- Rhodium-Catalyzed Enantioconvergent Isomerization of Homoallylic and Bishomoallylic Secondary Alcohols
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We present herein an unprecedented enantioselective isomerization of homoallylic and bishomoallylic secondary alcohols, catalyzed by a commercially available rhodium-complex and a base. This catalytic redox-neutral process provides an effective access to chiral ketones in high efficiency and enantioselectivity, without the use of any stoichiometric reagent or generation of any waste. For the reaction of homoallylic alcohols, this system achieved not only a stereoconvergent access to chiral ketones bearing a β-stereocenter (up to 95%, 86% ee) but also a concomitant oxidative kinetic resolution of the alcohol substrates (S > 20). In the case of bishomoallylic alcohols, an intriguing ligand-induced divergent reactivity was observed. A terminal-to-internal alkene isomerization promoted by Rh/L7 followed by redox isomerization using Rh/BINAP system produced chiral ketones bearing a γ-stereocenter with high yield and enantioselectivity. Mechanistic studies provided strong support for the redox-isomerization pathway with chain walking of the key alkyl-Rh intermediate.
- Huang, Rui-Zhi,Lau, Kai Kiat,Li, Zhaofeng,Liu, Tang-Lin,Zhao, Yu
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supporting information
p. 14647 - 14654
(2018/11/06)
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- SO2F2-Mediated Oxidative Dehydrogenation and Dehydration of Alcohols to Alkynes
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Direct synthesis of alkynes from inexpensive, abundant alcohols was achieved in high yields (greater than 40 examples, up to 95% yield) through a SO2F2-promoted dehydration and dehydrogenation process. This straightforward transformation of sp3-sp3 (C-C) bonds to sp-sp (C=C) bonds requires only inexpensive and readily available reagents (no transition metals) under mild conditions. The crude alkynes are sufficiently free of impurities to permit direct use in further transformations, as illustrated by regioselective Huisgen alkyne-azide cycloaddition reactions with PhN3 to give 1,4-substituted 1,2,3-traiazoles (16 examples, up to 92% yield) and Sonogashira couplings (10 examples, up to 77% yield).
- Zha, Gao-Feng,Fang, Wan-Yin,Li, You-Gui,Leng, Jing,Chen, Xing,Qin, Hua-Li
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supporting information
p. 17666 - 17673
(2019/01/04)
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- α-Alkylidene-γ-butyrolactone Formation via Bi(OTf)3-Catalyzed, Dehydrative, Ring-Opening Cyclizations of Cyclopropyl Carbinols: Understanding Substituent Effects and Predicting E/Z Selectivity
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A Bi(OTf)3-catalyzed ring-opening cyclization of (hetero)aryl cyclopropyl carbinols to form α-alkylidene-γ-butyrolactones (ABLs) is reported. This transformation represents different chemoselectivity from previous reports that demonstrated formation of (hetero)aryl-fused cyclohexa-1,3-dienes upon acid-promoted cyclopropyl carbinol ring opening. ABLs are obtained in up to 89% yield with a general preference for the E-isomers. Mechanistically, Bi(OTf)3 serves as a stable and easy to handle precursor to TfOH. TfOH then catalyzes the formation of cyclopropyl carbinyl cations, which undergo ring opening, intramolecular trapping by the neighboring ester group, subsequent hydrolysis, and loss of methanol resulting in the formation of the ABLs. The nature and relative positioning of the substituents on both the carbinol and the cyclopropane determine both chemo- and stereoselective outcomes. Carbinol substituents determine the extent of cyclopropyl carbinyl cation formation. The cyclopropane donor substituents determine the overall reaction chemoselectivity. Weakly stabilizing or electron-poor donor groups provide better yields of the ABL products. In contrast, copious amounts of competing products are observed with highly stabilizing cyclopropane donor substituents. Finally, a predictive model for E/Z selectivity was developed using DFT calculations.
- Sandridge, Matthew J.,McLarney, Brett D.,Williams, Corey W.,France, Stefan
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p. 10883 - 10897
(2017/10/27)
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- Palladium-Catalyzed Enantioselective Narasaka–Heck Reaction/Direct C?H Alkylation of Arenes: Iminoarylation of Alkenes
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A palladium-catalyzed reaction of γ,δ-unsaturated oxime esters with oxadiazoles afforded dihydropyrroles in good to excellent yields through an intramolecular iminopalladation/intermolecular direct heteroarene C?H alkylation cascade. This unprecedented iminoarylation of alkenes was subsequently realized in an enantioselective manner in the presence of a chiral bidentate phosphine ligand (Synphos).
- Bao, Xu,Wang, Qian,Zhu, Jieping
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supporting information
p. 9577 - 9581
(2017/08/01)
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- Nickel-catalyzed enantioselective hydrogenation of β-(acylamino)acrylates: Synthesis of chiral β-amino acid derivatives
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The nickel-catalyzed asymmetric hydrogenation of β-(acylamino)acrylates has been developed, affording chiral β-amino acid derivatives with excellent yields (95-99% yield) and enantioselectivities (97-99% ee). With the Ni-Binapine system, high enantioselectivities (98-99% ee) have also been obtained in the hydrogenation of Z/E isomeric mixtures of β-alkyl and β-aryl β-(acylamino)acrylates. The synthesis of chiral β-amino acid derivatives on a gram scale has also been achieved with 0.2 mol % catalyst loading.
- Li, Xiuxiu,You, Cai,Li, Shuailong,Lv, Hui,Zhang, Xumu
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supporting information
p. 5130 - 5133
(2017/11/06)
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- Copper-Catalysed Decarboxylative Trifluoromethylation of β-Ketoacids
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An efficient method for Cu-catalyzed decarboxylative trifluoromethylation of β-ketoacids to achieve α-trifluoromethyl ketones was developed. A wide variety of synthetically useful α-trifluoromethyl ketones were obtained in modest to good yields under mild reaction conditions. The present method also exhibits good functional-group compatibility.
- Xu, Xiaolan,Chen, Huanhuan,He, Jianbo,Xu, Huajian
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supporting information
p. 1665 - 1668
(2017/10/05)
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- Geminal Dichlorination of Phenyliodonium Ylides of β-Dicarbonyl Compounds through Double Ligand Transfer from (Dichloroiodo)benzene
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Pre-formed phenyliodonium ylides of cyclic and acyclic β-diketones, β-keto esters and β-diesters were reacted with (dichloroiodo)benzene, resulting in transfer of both chloride ligands onto the ylidic carbon. These two hypervalent iodine(III) compounds exhibit high reactivity towards each other under mild reaction conditions and typically afford the gem-dichloride products in good yield. Upon comparison of these chlorination reactions with those of the analogous diazocarbonyl compounds, reactions of iodonium ylides were unilaterally faster, and often gave the products in higher yield.
- Tao, Jason,Tuck, Tina N.,Murphy, Graham K.
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supporting information
p. 772 - 782
(2016/03/01)
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- Cooperative Indium(III)/Silver(I) System for Oxidative Coupling/Annulation of 1,3-Dicarbonyls and Styrenes: Construction of Five-Membered Heterocycles
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A cooperative indium(III)/silver(I) system for the synthesis of various five-membered heterocycles, including dihydrofurans, pyrroles, spirolactones, and spiroiminolactones, through the sequential oxidative coupling/annulation reaction of 1,3-dicarbonyl compounds with styrenes has been developed. Four different heterocyclic systems were successfully synthesized depending on the substitution pattern of the substrates using readily available starting materials. This system has the advantages of a broad substrate scope, moderate to good chemical yields, an operationally easy and simple procedure, and short reaction times. (Figure presented.) .
- Ko, Tae Yun,Youn, So Won
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supporting information
p. 1934 - 1941
(2016/07/06)
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- Stereoselective Michael Halogenation Initiated Ring Closure (MHIRC) Synthesis of Spirocyclopropanes from Benzylidenemalononitriles and 3-Arylisoxazol-5(4H)-ones
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The new chemical cascade reaction was found: the direct formation of substituted 4-oxo-2,7-diaryl-5-oxa-6-azaspiro[2.4]hept-6-ene-1,1-dicarbonitriles from benzylidenemalononitriles and 3-aryl-2-isoxazol-5(4H)-ones. The action of bromine on the equimolar mixture of benzylidenemalononitrile and 3-aryl-2-isoxazol-5(4H)-one in the basic alcohol solution results in stereoselective formation of spirobicycle containing the 2-isoxazolin-5-one and the cyclopropane fragments in 53-92% yields. Thus, the new simple and efficient ‘one-pot’ approach to substituted (2R*,3R*)-4-oxo-2,7-diaryl-5-oxa-6-azaspiro[2.4]hept-6-ene-1,1-dicarbonitriles was found directly from simple and reasonable starting compounds as benzylidenemalonitriles and 3-aryl-2-isoxazol-5(4H)-ones.
- Vereshchagin, Anatoly N.,Elinson, Michail N.,Korshunov, Alexander D.,Anisina, Yuliya E.,Novikov, Roman A.,Goloveshkin, Alexander S.,Bushmarinov, Ivan S.,Zlotin, Sergey G.,Egorov, Mikhail P.
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supporting information
p. 2489 - 2493
(2016/10/21)
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- Synthesis of enantiopure β-amino amides via a practical reductive amination of the corresponding β-keto amides
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A convenient and efficient reductive amination for the preparation of chiral β-amino amides is developed utilizing microwave heating. A variety of chiral β-keto amides react with ammonium acetate and sodium cyanoborohydride to afford the desired functionalized amines in good yields. This improved procedure takes advantage of microwave heating to significantly accelerate the reaction and offers a convenient and effective method to access some interesting molecules containing primary amine functionalities.
- Mtat, Dalila,Touati, Ridha,Ben Hassine, Béchir
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p. 6354 - 6358
(2014/12/11)
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- Base initiated aromatization/CO bond formation: A new entry to O-pyrazole polyfluoroarylated ethers
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A base initiated intermolecular SNAr reaction of pyrazolones with polyfluoroarenes was developed. The process involved the isomerization aromatization of pyrazolone followed by the CO bond formation via the selective CF bond cleavage. With this strategy, a wide range of O-pyrazole polyfluoroarylated ethers bearing diverse functional groups were synthesized in mild to good yields. Additionally, our method was also applied to the isoxazol substrates.
- Tang, Xiangyang,Chang, Jing,Liu, Cuibo,Zhang, Bin
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supporting information
p. 6534 - 6537
(2015/01/08)
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- Direct oxidative coupling of enamines and electron-deficient amines: TBAI/TBHP-mediated synthesis of substituted diaminoalkenes under metal-free conditions
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A metal-free cross-coupling of enamines and electron-de fi cient amines through oxidative C(sp2)-N bond formation has been realized by using TBAI as catalyst and TBHP as oxidant. This novel strategy allows for an efficient organocatalytic synthesis of the synthetically useful diaminoalkene derivatives and is highlighted by appealing features such as readily available of the starting materials, wide substrate scope and transition-metal-free characteristics. (Chemical Equation Presented).
- Yuan, Yucheng,Hou, Wenjuan,Zhang-Negrerie, Daisy,Zhao, Kang,Du, Yunfei
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supporting information
p. 5410 - 5413
(2015/01/09)
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- Rhodium-catalyzed enantioseletive hydrogenation of tetrasubstituted α-acetoxy β-enamido esters: A new approach to chiral α-hydroxyl-β-amino acid derivatives
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Asymmetric hydrogenation of tetrasubtitued α-acetoxy β-enamido esters with rhodium catalysts based on chiral diphosphine ligands provides an efficient and concise route to the synthesis of chiral α-hydroxyl-β-amino acid derivatives in excellent enantioselectivities. The products are valuable chiral building blocks in many biologically active compounds and have important applications in organic synthesis.
- Wang, Qingli,Huang, Wenhua,Yuan, Haoquan,Cai, Qin,Chen, Liming,Lv, Hui,Zhang, Xumu
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supporting information
p. 16120 - 16123
(2015/02/18)
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- Studies on the chemoenzymatic synthesis of (R)- and (S)-methyl 3-aryl-3-hydroxypropionates: The influence of toluene-pretreatment of lipase preparations on enantioselective transesterifications
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Two series (para- and meta-substituted) of racemic methyl esters of 3-aryl-3-hydroxypropionic acid were prepared after which the enantiomers were separated by an enzyme-catalyzed transesterification. Several lipases were investigated as the catalyst. The influence of the enzyme pretreatment, as well as substrate concentration, reaction temperature, stirring manner, and substrate conversion on the stereochemical outcome of the biotransformation process were investigated in detail. The best results were achieved by using solvent-pretreated lipase from Pseudomonas fluorescens or Burkholderia cepacia suspended in toluene, and vinyl acetate as the acetyl group donor.
- Borowiecki, Pawel,Bretner, Maria
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p. 925 - 936
(2013/09/23)
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- Formation of functionalized 2H-azirines through phio-mediated trifluoroethoxylation and azirination of enamines
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A variety of enaminones and enamine carboxylic esters were converted to trifluoroethoxylated 2H-azirines through reactions with PhIO in trifluoroethanol (TFE). The cascade reaction is postulated to proceed via a PhIO-mediated oxidative trifluoroethoxylation and a subsequent azirination of the α-trifluoroethoxylated enamine intermediates.
- Sun, Xiaoqian,Lyu, Youran,Zhang-Negrerie, Daisy,Du, Yunfei,Zhao, Kang
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supporting information
p. 6222 - 6225
(2014/01/17)
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- HETEROCYCLIC COMPOUNDS FOR THE INHIBITION OF PASK
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Disclosed herein are new heterocyclic compounds and compositions and their application as pharmaceuticals for the treatment of disease. Methods of inhibiting PAS Kinase (PASK) activity in a human or animal subject are also provided for the treatment of diseases such as diabetes mellitus.
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Page/Page column 73
(2012/11/08)
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- HOTf mediated cascade reactions of 1-arenoylcyclopropanecarboxylic acids with arenes
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The cascade reactions of 1-arenoylcyclopropanecarboxylic acids with arenes proceed smoothly in freshly distilled HOTf to give the corresponding tetrahydro-5H-benzo[c]fluorene derivatives in good yields along with high stereoselectivities under mild conditions. The Royal Society of Chemistry.
- Chen, Gen-Qiang,Tang, Xiang-Ying,Shi, Min
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supporting information; scheme or table
p. 2340 - 2342
(2012/04/18)
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- Cross-dehydrogenative coupling between enamino esters and ketones: Synthesis of tetrasubstituted pyrroles
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Tetrasubstituted pyrroles have been synthesized via the cross-dehydrogenative coupling between enamino esters and acetone. Silver carbonate proved to be an effective oxidant, and no transition metal catalyst is necessary.
- Zhao, Miao,Wang, Fen,Li, Xingwei
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supporting information; experimental part
p. 1412 - 1415
(2012/05/04)
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- Ambient carboxylation on a supported reversible CO2 carrier: Ketone to β-keto ester
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A reversible CO2 carrier (RCC) has been developed to perform carboxylation of ketone to β-ketoester under ambient CO2 pressure and temperature. RCC has been synthesized by immobilizing 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) on methylhydrosiloxane support and reacting with CO2 with 100% degree of functionalisation. RCC is found to be recyclable and shows retention of activity in 5 recycles. CO2 absorption under ambient temperature and desorption at 120°C renders the material suitable for carrying out carboxylation reactions at 25°C with excellent yields. The yield of the reaction can reach up to 100% with TON 200 in 4 h. The extent of the reaction primarily depends upon enol content of the substrate. β-Ketoacid produced during the reaction can be isolated and converted to its corresponding methyl ester derivative by reacting with methyl iodide.
- Beckman, Eric J.,Munshi, Pradip
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experimental part
p. 376 - 383
(2011/04/17)
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- Gold/copper-catalyzed activation of the aci-form of nitromethane in the synthesis of methylene-bridged bis-1,3-dicarbonyl compounds
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Activation of the aci-form of nitromethane using Lewis acids for the attack of carbon nucleophiles was studied. 1,3-Dicarbonyl compounds in the presence of catalytic amounts of AuCl3 or Cu(OTf)2 in nitromethane solvent could be converted into methylene-bridged bis-1,3-dicarbonyl compounds.
- Balamurugan, Rengarajan,Manojveer, Seetharaman
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supporting information; experimental part
p. 11143 - 11145
(2011/11/05)
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- Preparation and evaluation of trisubstituted pyrimidines as phosphatidylinositol 3-kinase inhibitors. 3-Hydroxyphenol analogues and bioisosteric replacements
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Two classes of trisubstituted pyrimidines related to PI-103 1 have been prepared and their inhibitory activities against phosphatidylinositol 3-kinase (PI3K) p110α were determined. From those with direct 6-aryl substitution compound 11a was the most potent inhibitor with an IC50 value of 62 nM, and showed similar activity against other class 1a PI3K isoforms tested, p110β and p110γ. When a linking chain was introduced, as in the second exemplified class, compound 15f inhibited p110α with IC 50 142 nM, and showed greater selectivity towards p110α. Compounds of both classes showed promising inhibition of cellular proliferation in IGROV-1 ovarian cancer cells. Among compounds designed to replace the 3-phenolic motif with structural isosteres, analogues incorporating a 4-indazolyl group possessed enzyme and cellular activities comparable to the parent phenols.
- Large, Jonathan M.,Torr, Jane E.,Raynaud, Florence I.,Clarke, Paul A.,Hayes, Angela,Stefano, Francesca Di,Urban, Frederique,Shuttleworth, Stephen J.,Saghir, Nahid,Sheldrake, Peter,Workman, Paul,McDonald, Edward
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scheme or table
p. 836 - 851
(2011/03/19)
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- Synthesis and biological activity of new (E)-α-(Methoxyimino) benzeneacetate derivatives containing a substituted pyrazole ring
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Strobilurins are one of the most important classes of agricultural fungicides. To discover new strobilurin analogues with high activity, a series of new strobilurin derivatives containing a substituted pyrazole in the side chain were synthesized and their biological activities were tested. The compounds were identified by 1H nuclear magnetic resonance, infrared, and elemental analysis. The test results indicated that the compounds exhibited strong fungicidal activities against Pyricularia oryzae, Phytophthora infestans, Pseudoperonospora cubenssi, and Erysiphe graminis. The relationship between structure and biological activity is discussed in terms of the effects of the substituents on the pyrazole ring. The present work demonstrates that strobilurin analogues with a 3-(substituted phenyl)-1 H-pyrazol-5-oxy side chain can be used as possible lead compounds for the development of potential agrochemicals.
- Li, Miao,Liu, Chang-Ling,Yang, J.I.-Chun,Zhang, Jin-B.O.,Li, Zhi-Nian,Zhang, Hong,Li, Zheng-Ming
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experimental part
p. 2664 - 2667
(2011/08/05)
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- Iron-catalyzed selective oxidation of N-methyl amines: highly efficient synthesis of methylene-bridged bis-1,3-dicarbonyl compounds
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Methylene-bridged bis-1,3-dicarbonyl derivatives were synthesized efficiently by Iron-catalyzed oxidative reactions of 1,3-dicarbonyl compounds and N,N-dimethylaniline. Blpyrazoles and substituted 1,4-dlhydropyridlne were obtained by the reactions of bis-1,3-dicarbonyl compounds with hydrazines and ammonium acetate, respectively.
- Li, Haijun,He, Zhiheng,Guo, Xingwel,Li, Wenjuan,Zhao, Xuhul,Ll, Zhlplng
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supporting information; experimental part
p. 4176 - 4179
(2009/12/30)
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- Highly enantioselective synthesis of β-amino acid derivatives by the lewis base catalyzed hydrosilylation of β-enamino esters
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A study was conducted to demonstrate highly enantioselective synthesis of β-amino acid derivatives by the Lewis base catalyzed hydrosilylation of βenamino esters. It was found that these catalyst and its analogue displayed excellent activities and enantioselectivities in promoting hydrosilylation of N-aryl β-enamino esters. N-picolinoylpyrrolidine derivatives and N-picolioylephedrine were also evaluated in hydrosilylation of (Z)-methyl 3-phenyl-3-(phenylamino)acrylate. The generality of the Lewis base organocatalyzed hydrosilylation of various β-enamino esters were examined under the optimized conditions. It was observed that the catalytic system exhibited a high sensitivity to the N-substituents, while all the N-aryl β-enamino esters underwent the hydrosilylation smoothly to give corresponding β-amino esters.
- Zheng, Hong-Jie,Chen, Wen-Bing,Wu, Zhi-Jun,Deng, Jin-Gen,Lin, Wen-Qing,Yuan, Wei-Cheng,Zhang, Xiao-Mei
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supporting information; experimental part
p. 9864 - 9867
(2009/10/02)
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- INHIBITORS OF HUMAN IMMUNODEFICIENCY VIRUS REPLICATION
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The invention relates to compounds of formula (I) their derivatives comprising a detectable label, their compositions and their use in the treatment of human immunodeficiency virus (HIV) infection. In particular, the invention provides novel inhibitors of
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Page/Page column 48-49
(2008/06/13)
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- Enantioselective Hydrogenation of β-Keto Esters using Chiral Diphosphine-Ruthenium Complexes: Optimization for Academic and Industrial Purposes and Synthetic Applications
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Enantioselective hydrogenation using chiral complexes between atropisomeric diphosphines and ruthenium is a powerful tool for producing chiral compounds. Using a simple and straightforward in situ catalyst preparation, the conditions were optimized using molecular hydrogen for both academic and industrial purposes. This led to the best conditions and the lowest catalytic ratio required for the pressure used. Hydrogenation of various β-keto esters was efficiently performed at atmospheric and higher pressures, leading to the use of very low catalyst-substrate ratios up to 1/20,000. Asymmetric hydrogenations were used in key-steps towards the total synthesis of corynomycolic acid, Duloxetine and Fluoxetine.
- Ratovelomanana-Vidal,Girard,Touati,Tranchier,Ben Hassine,Genet
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p. 261 - 274
(2007/10/03)
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- Reaction of methyl diazoacetate with aldehydes, amines, thiols, alcohols and acids over transition metal-exchanged clays
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Metal-exchanged clays (M = Rh and Cu) catalyze effectively the reaction of methyl diazoacetate with various aldehydes, affording the corresponding β-keto esters in high yields. They have also been effective in the decomposition of methyl diazoacetate to form metallocarbenes which, in turn, successfully insert into X-H (X = N, O, S, CO2) bonds of a variety of amines, aldehydes, thiols and acids, thereby producing the corresponding esters. The Royal Society of Chemistry 1999.
- Phukan, Prodeep,Mohan, Jakkam Madan,Sudalai, Arumugam
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p. 3685 - 3689
(2007/10/03)
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- Insecticidal Activity of Sesquilignans with a 3-Aryl-6-methoxy-2-methoxymethyl-1,4-benzodioxanyl Group
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Five analogs of the insecticidal lignan of the Phryma were synthesized by modifying its 3,4-methylenedioxyphenyl group with a phenyl, 4-methoxyphenyl, 3-methoxyphenyl, 3,4-dimethoxyphenyl, or 4-chlorophenyl group to evaluate the contribution of the methylenedioxy function to the activity.The assay results revealed that the 4-oxymethylene part of the 3,4-methylenedioxyphenyl group collaborated more for strengthening the insecticidal activity than the 3-oxymethylene part did.Unexpectedly, the 3,4-dimethoxyphenyl analog was totally inactive, even at a high dose level.
- Yamauchi, Satoshi,Ishibashi, Fumito,Taniguchi, Eiji
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p. 1760 - 1768
(2007/10/02)
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- N-aryl-3-aryl-4,5-dihydro-1H-pyrazole-1-carboxamides and methods of their production
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This invention relates to novel N-aryl-3-aryl-4,5-dihydro-1H-pyrazole-1-carboxamide compounds which are useful as pesticides, compositions containing those compounds, methods of controlling pests and processes for preparing these compounds.
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- Insecticidal n-aryl-3-aryl-4,5-dihydro-1h-pyrazole-1-carboxamides
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This invention relates to N-aryl-3-aryl-4,5-dihydro-1H-pyrazole-1-carboxamide compounds which are useful as pesticides, compositions containing those compounds, methods of controlling pests and processes for preparing these compounds.
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