- Protective Effect of a Novel (2S, 3R, 4S)-Chromene-3-Carboxamide Derivative, Z20 Against Sepsis-Induced Organ Injury
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Sepsis, a systemic inflammatory response mediated by excessive production of diverse inflammatory cytokines, remains the vital cause of morality in the intensive care unit (ICU). TLR4-MD2 (toll-like receptor 4-myeloid differentiation factor 2) complex activated by LPS serves as an effective target to decrease the inflammation during sepsis. In this study, we evaluated the effects of a new small molecule Z20 structural based on (2S, 3R, 4S)-chromene-3-carboxamide on LPS-induced sepsis in mice. We found Z20 markedly improved the survival rate and attenuated the multiply organs injury after LPS administration?in mice. In addition, Z20 significantly alleviated organ inflammation as characterized by diminished inflammatory factors expression in vivo. Furthermore, by employing surface plasmon resonance (SPR) experiment, we identified that TLR4-MD2 complex?was the potential target for Z20. Finally, we performed the safety assessment experiment to confirm the safety of Z20 in vivo. In conclusion, Z20, as a potential TLR4-MD2 inhibitor, effectively attenuated LPS-induced organ injury and inflammation.
- Chen, Peng,Li, Na,Niu, Mengwei,Wang, Yong,Wang, Yuhang,Zeng, Liyan
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- Phenothiazine and amide-ornamented dihydropyridines: Via a molecular hybridization approach: Design, synthesis, biological evaluation and molecular docking studies
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A series of novel phenothiazinyldihydropyridine dicarboxamides 7a-7j was synthesized by adopting a multi-step synthetic strategy and characterized through physical and spectral techniques. Among them, the chemical entities with para-fluoro (7d), ortho-bromo and-fluoro (7f and 7i), ortho- A nd para-methyl (7e) and meta- A nd para-methoxy (7h) substituents exhibited either similar or superior anti-inflammatory activities with respect to the standard drug diclofenac sodium. Besides, the chemical entities with ortho-bromo and-fluoro substituents as well as meta-nitro substituents (7f, 7g and 7i) showed enhanced radical scavenging activities when compared to standard ascorbic acid. Furthermore, anticancer studies revealed that the meta- A nd para-chloro-substituted molecule 7a exerted the best activity against all the pancreatic cancer cells tested. Also, appreciable binding affinity (-8.10 kcal mol-1) was observed during molecular docking between B-cell lymphoma 2 and 7a. The structural diversifications of the potent chemical entities besides further exploration in connection with the biological profiles of the same are underway.
- Sivaramakarthikeyan, Ramar,Iniyaval, Shunmugam,Padmavathy, Krishnaraj,Liew, Hui-Shan,Looi, Chin-King,Mai, Chun-Wai,Ramalingan, Chennan
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- Synthesis of heterocyclic systems with carbohydrate fragment: 2. Stereoselective synthesis of tetrahydropyridones by reaction of levoglucosenone with amides of α-methylene-active acids
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The reactions of levoglucosenone with amides of several α-nitrocarboxylic acids and acetoacetic acid result in tetrahydropyridones fused with a carbohydrate fragment. In the case of acetoacetic acid amides, mixtures of keto and enol tautomers were obtained. The stereochemistry of cyclization is discussed in detail.
- Samet,Kislyi,Chernyshova,Reznikov,Ugrak,Semenov
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- A facile and selective procedure for transesterification of β-keto esters promoted by yttria-zirconia based lewis acid catalyst
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An yttria-zirconia based strong Lewis acid efficiently catalyses the transesterification of β-keto esters under environmentally safe, heterogeneous reaction conditions with high selectivity and in good to excellent yields.
- Kumar, Pradeep,Kumar Pandey, Rajesh
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- Microwave induced acetoacetylation of hetaryl and aryl amines
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Acetoacetylation of hetaryl and aryl amines by interaction with ethyl acetoacetate under microwave irradiation, without any catalyst and/or solvent, is reported.
- Suri,Satti,Suri
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- Microwave-promoted direct amidation of unactivated esters catalyzed by heteropolyanion-based ionic liquids under solvent-free conditions
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Abstract A simple and efficient procedure for the synthesis of amides directly from unactivated esters and amines catalyzed by heteropolyanion-based ionic liquids under microwave-promoted and solvent-free conditions has been reported. The practical protocol was found to be compatible with different structurally diverse substrates. Moderate to excellent yields, solvent-free media, and operational simplicity are the main highlights. Furthermore, the heteropolyanion-based ionic liquids were easily reusable for this amidation.
- Fu, Renzhong,Yang, Yang,Ma, Yunsheng,Yang, Fei,Li, Jingjing,Chai, Wen,Wang, Quan,Yuan, Rongxin
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- Vinyl polymerizations of norbornene catalyzed by nickel complexes with acetoacetamide ligands
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On the basis of a remote effect, a series of acetoacetamide ligands and corresponding nickel complexes N-(R-phenyl) acetoacetamide Ni(CH2Ph) (PMe3) (R = H, 1; R = 2-methyl, 2; R = 2,6-dimethyl, 3; R = 2,6-diisopropyl, 4; R = 4-NO2, 5) were synthesized and characterized. The solid structure of complex 3 was confirmed by X-ray single-crystal analysis to be of cis form. 1H and 31P NMR spectroscopy confirmed that cis and trans isomers of nickel complexes were present in solution. Norbornene polymerizations with acetoacetamide nickel complexes activated with modified methylaluminoxane (MMAO) were investigated in detail. Remote steric and electronic effects of acetoacetamide ligand on catalytic activity and molecular weight of polynorbornenes (PNBs) were observed. Characterizations of the obtained PNBs show that the obtained polymer products are non-crystalline vinylic-addition polynorbornenes. Copyright
- Feng, Qian,Chen, Dajun,Feng, Danyang,Jiao, Libin,Peng, Zhigang,Pei, Lixia
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- Mild and high-yielding synthesis of β-keto esters and β-ketoamides
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In the presence of sodium acetate, the reaction between 2,2,6-trimethyl-4H-1,3-dioxin-4-one and secondary or tertiary alcohols (including chiral ones) or primary or secondary amines could be carried out in refluxing tetrahydrofuran, under much milder conditions than those described in the literature. In these new conditions, side products normally observed using the traditional protocol were avoided, and-keto esters and-ketoamides were normally obtained in quantitative yields.
- Sridharan, Vellaisamy,Ruiz, Miriam,Menendez, J. Carlos
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- Phenothiazine and amide-ornamented novel nitrogen heterocyclic hybrids: synthesis, biological and molecular docking studies
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The synthesis of novel hybrids, namely, phenothiazine and amide-ornamented nitrogen heterocycles (25-34) has been accomplished utilizing a multi-step synthetic protocol and the structures have been established based on physical and spectral techniques. Of these, the hybrids possessing meta-nitro (26), para-fluoro (28), meta- and para-methyl (31), ortho-bromo (33) and ortho- and para-dimethyl (34) phenyl carboxamide scaffolds exhibited superior anti-inflammatory profiles over the standard diclofenac sodium. A hybrid integrated with a para-fluorophenyl carboxamide moiety (28) showed the highest DPPH radical scavenging activity among the chemical entities synthesized. Furthermore, the results of anticancer evaluations implied that the hybrid tethered with a phenyl carboxamide structural unit (29) exerted superior activity when compared with other hybrids against the pancreatic cancer cells SW1990 and AsPC1. Molecular docking between the hybrid 29 and B-cell lymphoma 2 reflects its appreciable binding affinity (-8.84 kcal mol-1). The results revealed that these chemical entities can serve as potent biological agents and/or efficient intermediates for the construction of potent biological agents.
- Iniyaval, Shunmugam,Karuppasamy, Ayyanar,Lim, Wei-Meng,Mai, Chun-Wai,Padmavathy, Krishnaraj,Ramalingan, Chennan,Sivaramakarthikeyan, Ramar
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- Palladium-catalyzed tandem diperoxidation/C - H activation resulting in diperoxy-oxindole in air
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A highly efficient and facile palladium-catalyzed tandem diperoxidation and C - H activation process was reported, which provides a new pathway for the synthesis of biologically active diperoxides as well as oxindole derivatives from readily available starting materials in excellent chemical yields.
- An, Guanghui,Zhou, Wei,Zhang, Guangqian,Sun, Hao,Han, Jianlin,Pan, Yi
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- Transacetoacetylation with tert-Butyl Acetoacetate: Synthetic Apllications
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Reaction of various nucleophiles with tert-butyl acetoacetate (t-BAA, 1a) is shown to be a convenient method for the preparation of a wide variety of acetoacetic acid derivatives.This material can be used to prepare acetoacetates and acetoacetamides from a wide variety of alcohols and amines.Reaction of 1a with an unhindered primary amine such as n-heptylamine under standard conditions gives unwanted byproducts due to the formation of the enamines 24 and 25.Formation of these byproducts can be minimized by dilution and/or altering the mode of addition.
- Witzeman, J. Stewart,Nottingham, W. Dell
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- Vibrational, NMR and quantum chemical investigations of acetoacetanilde, 2-chloroacetoacetanilide and 2-methylacetoacetanilide
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The vibrational assignment and analysis of the fundamental modes of the compounds acetoacetanilide (AAA), 2-chloroacetoacetanilide (2CAAA) and 2-methylacetoacetanilide (2MAAA) have been performed. Density functional theory studies have been carried out with B3LYP method utilising 6-311++G ** and cc-pVTZ basis sets to determine structural, thermodynamic and vibrational characteristics of the compounds and also to understand the influence of chloro and methyl groups on the characteristic frequencies of amide (-CONH-) group. intramolecular hydrogen bond exists in acetoacetanilide and o-substituted acetoacetanilide molecules and the N?O distance is found to be around 2.7 ?. The 1H and 13C nuclear magnetic resonance chemical shifts of the molecules were determined and the same have been calculated using the gauge independent atomic orbital (GiAO) method. The energies of the frontier molecular orbitals have been determined. in AAA, 2CAAA and 2MAAA molecules, the nN → pπ*co Interaction between the nitrogen lone pair and the amide C=O antibonding orbital gives strong stabilization of 64.75, 62.84 and 64.18 kJ mol 1, respectively. The blue shift in amide-ii band of 2MAAA is observed by 45-50 cm1 than that of AAA. The steric effect of ortho methyl group significantly operating on the N-H bond properties. The amide-iii, the C-N stretching mode of methyl and chloro substituted aceto-acetanilide compounds are not affected by the substitution while the amide-V band, the N-H out of plane bending mode of 2-chloroacetoacetanilide compound is shifted to a higher frequency than that of AAA. The substituent chlorine plays significantly and the blue shift in o-substituted compounds than the parent in the amide-V vibration is observed. The amide-Vi, C=O out of plane bending modes of 2MAAA and 2CAAA are significantly raised than that of AAA. A blue shift of amide-Vi, C=O out of plane bending modes of 2MAAA and 2CAAA than AAA is observed.
- Arjunan,Kalaivani,Senthilkumari,Mohan
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- Nickel-promoted oxidative domino Csp3-H/N-H bond double-isocyanide insertion reaction to construct pyrrolin-2-ones
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The first nickel-catalyzed oxidative domino Csp3-H/N-H double isocyanide insertion reaction of acetamides with isocyanides has been developed for the synthesis of pyrrolin-2-one derivatives. A wide range of acetamides bearing various functional groups are compatible with this reaction system by utilizing Ni(acac)2as a catalyst. In this transformation, isocyanide could serve as a C1 connector and insert into the inactive Csp3-H bond, representing an effective way to construct heterocycles.
- Wen, Li-Rong,Wang, Ning-Ning,Du, Wu-Bo,Ma, Qiang,Zhang, Lin-Bao,Li, Ming
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supporting information
p. 2895 - 2900
(2021/04/14)
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- Ru-NHC-Catalyzed Asymmetric Hydrogenation of 2-Quinolones to Chiral 3,4-Dihydro-2-Quinolones
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Direct enantioselective hydrogenation of unsaturated compounds to generate chiral three-dimensional motifs is one of the most straightforward and important approaches in synthetic chemistry. We realized the Ru(II)-NHC-catalyzed asymmetric hydrogenation of 2-quinolones under mild reaction conditions. Alkyl-, aryl- and halogen-substituted optically active dihydro-2-quinolones were obtained in high yields with moderate to excellent enantioselectivities. The reaction provides an efficient and atom-economic pathway to construct simple chiral 3,4-dihydro-2-quinolones. The desired products could be further reduced to tetrahydroquinolines and octahydroquinolones.
- Daniliuc, Constantin,Glorius, Frank,Hu, Tianjiao,Lückemeier, Lukas
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supporting information
p. 23193 - 23196
(2021/09/25)
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- Dichloromeldrum's acid (DiCMA): A practical and green amine dichloroacetylation reagent
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Dichloromeldrum's acid is introduced as a bench-stable, nonvolatile reagent for the dichloroacetylation of anilines and alkyl amines to produce α,α-dichloroacetamides, which are important motifs for medicinal chemistry. Products are formed in good to excellent yields with reagent grade solvents, and, as the only byproducts are acetone and CO2, no column chromatography is required. Thus, this reagent is practical, efficient, and green for the dichloroacetylation of primary amines.
- Heard, David M.,Lennox, Alastair J.J.
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supporting information
p. 3368 - 3372
(2021/05/06)
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- HFIP-mediated strategy towards β-oxo amides and subsequent Friedel-Craft type cyclization to 2?quinolinones using recyclable catalyst
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A simple and cost-effective 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP)-mediated protocol for the synthesis of β-oxo amides has been described by using amines and β-keto esters as substrates. The reaction conditions were found to be highly efficient towards the cleavage of C[sbnd]O bond and consequent formation of the products in excellent yields and selectivity. The obtained β-oxo amides were further transformed in to the synthetically useful 2?quinolinones via intramolecular Friedel-Craft type cyclization of aromatic ring using ferrites as a recyclable catalyst. A spectrum of substrates bearing broad range of functional groups were well tolerated under the reaction conditions. The proposed mechanistic pathways were substantially verified by literature and mass-spectroscopic evidences.
- Kabi, Arup K.,Gujjarappa, Raghuram,Vodnala, Nagaraju,Kaldhi, Dhananjaya,Tyagi, Ujjawal,Mukherjee, Kalisadhan,Malakar, Chandi C.
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supporting information
(2020/10/20)
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- Enantioselective α-Amination of Acyclic 1,3-Dicarbonyls Catalyzed by N-Heterocyclic Carbene
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Herein, we describe a method for the catalytic enantioselective α-amination of α-substituted acyclic 1,3-ketoamides and 1,3-amidoesters that affords the products possessing N-substituted quaternary stereocenters with a chiral N-heterocyclic carbene (NHC). The reaction is based on the utilization of an intrinsic Br?nsted base characteristic of NHC that enables the catalytic formation of a chiral ion pair comprising the enolate and the azolium ion. A series of challenging open-chain α-substituted 1,3-dicarbonyls are aminated via this method with ee's of ≤99%.
- Santra, Surojit,Maji, Ujjwal,Guin, Joyram
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supporting information
p. 468 - 473
(2020/02/04)
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- Structure-Activity Relationship Studies of Tetrahydroquinolone Free Fatty Acid Receptor 3 Modulators
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Free fatty acid receptor 3 (FFA3, previously GPR41) is activated by short-chain fatty acids, mediates health effects of the gut microbiota, and is a therapeutic target for metabolic and inflammatory diseases. The shortage of well-characterized tool compounds has however impeded progress. Herein, we report structure-activity relationship of an allosteric modulator series and characterization of physicochemical and pharmacokinetic properties of selected compounds, including previous and new tools. Two representatives, 57 (TUG-1907) and 63 (TUG-2015), showed improved solubility and preserved potency. Of these, 57, with EC50 = 145 nM and a solubility of 33 μM, showed high clearance in vivo but is a preferred tool in vitro. In contrast, 63, with EC50 = 162 nM and a solubility of 9 μM, showed lower clearance and seems better suited for in vivo studies. Using 57, we demonstrate for the first time that FFA3 activation leads to calcium mobilization in murine dorsal root ganglia.
- Ulven, Elisabeth Rexen,Quon, Tezz,Sergeev, Eugenia,Barki, Natasja,Brvar, Matjaz,Hudson, Brian D.,Dutta, Palash,Hansen, Anders H?jgaard,Bielefeldt, Line O.,Tobin, Andrew B.,McKenzie, Christine J.,Milligan, Graeme,Ulven, Trond
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p. 3577 - 3595
(2020/04/30)
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- 2- Amino -3,4-dihydropyran -3- formamide analogue as well as preparation method and application thereof
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The invention relates to a preparation method 2 - of a compound containing, amino - 333384-dihydropyran - 3 3, which comprises the following step :1) of linking diketene with R. 2 NH2 The reaction is stirred in a solvent to complete. ;2) Is added R. 3 NH2 , R1 CHO And a of Compound, and adding elemental iodine to reaction solution to complete curing, and drying the filter cake to obtain compound 2 - containing. amino - 3333,4-dihydropyran - 3 3-carboxamide compound, according to the present invention as well as its use. without isolation of intermediate, in a simple.
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Paragraph 0094-0096
(2020/03/25)
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- Pd-catalyzed amidation of 1,3-diketones with CO and azidesviaa nitrene intermediate
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An efficient Pd-catalyzed amidation of 1,3-diketones has been developed using carbon monoxide and organic azides. This reaction provides a step-economic approach to produce β-ketoamides from readily available compounds under mild ligand-, oxidant-, and base-free conditions. The mechanistic studies showed that the reaction occurred through anin situgenerated isocyanate intermediate.
- Gu, Zheng-Yang,Chen, Jie,Xia, Ji-Bao
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supporting information
p. 11437 - 11440
(2020/10/12)
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- Design, synthesis, and molecular docking study of new monastrol analogues as kinesin spindle protein inhibitors
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Lung, colorectal, and breast cancers are the top three types of cancer by incidence and are responsible for one-third of the cancer incidence and mortality. A series of 18 3,4-dihydropyrimidine analogues bearing a 1,2-methylenedioxybenzene component at position 4 with diverse side chains at positions 5 and 6 was designed and synthesized as inhibitors of the Eg5 kinesin enzyme. Target compounds were screened for their anticancer activity according to the NCI-USA protocol toward a panel of 60 cancer cell lines. Compounds 12a and 12b displayed the best antiproliferation activity against many cell lines. Interestingly, compound 12a displayed lethal effects against non-small-cell lung cancer NCI-H522 cells (?42.26%) and MDA-MB-468 breast cancer cells (?1.10%) at a single-dose assay concentration of 10?5 M. Compounds 11c, 11d, 11g, 12a–d, 13, 15, and 18a were assayed against the kinesin enzyme, with IC50 values ranging from 1.2 to 18.71 μM, which were more potent compared with monastrol (IC50 = 20 μM). Cell cycle analysis of NCI-H522 cells treated with compound 12a showed cell cycle arrest at the G2/M phase. Furthermore, the expression levels of active caspase-3 and -9 were measured. A molecular docking study was performed for some demonstrative compounds as well as monastrol docked into the allosteric binding site of the kinesin spindle protein.
- El-Hamamsy, Mervat H.,Sharafeldin, Nabaweya A.,El-Moselhy, Tarek F.,Tawfik, Haytham O.
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- 5-Aminothiophene-2,4-dicarboxamide analogues as hepatitis B virus capsid assembly effectors
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Chronic hepatitis B virus (HBV) infection represents a major health threat. Current FDA-approved drugs do not cure HBV. Targeting HBV core protein (Cp) provides an attractive approach toward HBV inhibition and possibly infection cure. We have previously identified and characterized a 5-amino-3-methylthiophene-2,4-dicarboxamide (ATDC) compound as a structurally novel hit for capsid assembly effectors (CAEs). We report herein hit validation through studies on absorption, distribution, metabolism and excretion (ADME) properties and pharmacokinetics (PK), and hit optimization via analogue synthesis aiming to probe the structure-activity relationship (SAR) and structure-property relationship (SPR). In the end, these medicinal chemistry efforts led to the identification of multiple analogues strongly binding to Cp, potently inhibiting HBV replication in nanomolar range without cytotoxicity, and exhibiting good oral bioavailability (F). Two of our analogues, 19o (EC50 = 0.11 μM, CC50 > 100 μM, F = 25%) and 19k (EC50 = 0.31 μM, CC50 > 100 μM, F = 46%), displayed overall lead profiles superior to reported CAEs 7–10 used in our studies.
- Tang, Jing,Huber, Andrew D.,Pineda, Dallas L.,Boschert, Kelsey N.,Wolf, Jennifer J.,Kankanala, Jayakanth,Xie, Jiashu,Sarafianos, Stefan G.,Wang, Zhengqiang
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supporting information
p. 179 - 192
(2019/01/04)
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- NEW ANALOGS AS ANDROGEN RECEPTOR AND GLUCOCORTICOID RECEPTOR MODULATORS
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The present invention relates to novel dihydropyridine derivatives of formula (I): as modulators of nuclear receptors selected from androgen receptor and glucocorticoid receptor, to processes for their preparation, to pharmaceutical compositions comprising said compounds and to the use of said for manufacturing a medicament for the treatment of pathological conditions or diseases that can improve by modulation of androgen receptor and/or glucocorticoid receptor, selected from cancer, metastasizing cancers, benign prostate hyperplasia, polycystic ovary syndrome (PCOS), hair loss, hirsutism, acne, hypogonadism, muscle wasting diseases, cachexia, Cushing's syndrome, anti-psychotic drug induced weight gain, obesity, post-traumatic stress disorder and alcoholism.
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Paragraph 0194; 0196; 0222
(2019/05/16)
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- Synthesis of β-Ketoamide Curcumin Analogs for Anti-Diabetic and AGEs Inhibitory Activities
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Two different series of novel β-ketoamide curcumin analogs enriched in biological activities have been synthesized. The synthesized compounds were screened for their in?vitro anti-diabetic and AGEs inhibitory activities and exhibited potent to good anti-diabetic and AGEs inhibitory activities. The molecular docking study was also performed with the α-amylase enzyme.
- Banuppriya, Govindharasu,Sribalan, Rajendran,Fathima, Sulthan Alavudeen Rizwan,Padmini, Vediappen
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- Synthesis and anticancer activity evaluation of some new derivatives of 2-(4-benzoyl-1-piperazinyl)-quinoline and 2-(4-cinnamoyl-1-piperazinyl)-quinoline
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In this study, we designed and synthesized twenty new derivatives of 2-(4-benzoyl-1-piperazinyl)- quinoline and 2-(4-cinnamoyl-1-piperazinyl)-quinoline with potential anticancer activity. The structures of synthesized compounds were confirmed by 1H and 13C NMR spectroscopy and MS spectrometry. The activity of novel compounds was evaluated in the cell viability assay as well as in the wound healing assay. Presented data show that examined substances have anticancer activity in cell culture. Seven compounds which showed a high rate of cell growth inhibition were selected for further studies. Three of them strongly reduced the growth of B16F10 cells. The novel compounds constitute a good base for further studies and optimization of structure for new therapeutically effective anti-cancerous drugs.
- Kubica, Krzysztof P.,Taciak, Przemys?aw P.,Czajkowska, Agnieszka,Stokfisz-Ignasiak, Alicja,Wyrebiak, Rafa?,Podsadni, Piotr,M?ynarczuk-Bia?y, Izabela,Malejczyk, Jacek,Mazurek, Aleksander P.
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p. 891 - 901
(2018/09/25)
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- Synthesis of acetoacetanilide
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The invention relates to synthesis of acetoacetanilide. The synthesis comprises the following steps: weighing 5.31 mmol of ethyl acetoacetate, 5.31 mmol of phenylamine and 0.531 mmol of 4-dimethylamino pyridine, adding the weighed materials into a single-opening bottle with the volume of 25 mL, then adding 10 to 30 mL of methylbenzene, performing heating reflux under stirring for 20 to 36 hours, monitoring the raw materials by using thin layer chromatography (petroleum ether: ethyl acetate=4: 1, and Rf=0.37), ending the reaction after the raw materials disappear, adding water, transferring a reaction solution into a separating funnel, performing extracting with ethyl acetate (20 mL x 3), performing collecting to obtain an organic phase, washing the organic phase with saturated sodium chloride, performing drying with anhydrous MgSO4, performing filtering to remove solids, collecting the obtained filtrate, performing rotary evaporateion on the filtrate, and performing column chromatography separation with a mixture (petroleum ether: ethyl acetate=10: 1) serving as an eluent to obtain acetoacetanilide which is a target compound.
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Paragraph 0006; 0007
(2017/05/20)
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- Synthesis of 4-aryl-2,6-dimethyl-3,5-bis-N-(aryl)-carbamoyl-1,4-dihydropyridines as novel skin protecting and anti-aging agents
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A series of 4-aryl-2,6-dimethyl-3,5-bis-N-(aryl)-carbamoyl-1,4-dihydropyridines 6a-6h were prepared by using the one-pot three component synthetic method. The target compounds 6a-6h were synthesized by reacting two molar equivalents of ketone functionality and one mole of aromatic aldehydes in ammonium acetate to obtain the desired products. The structures of newly synthesized compounds were characterized by FT-IR, 1H-NMR, 13C-NMR, and elemental analysis. All the synthesized compounds were screened for their elastase inhibition and antioxidant activity. Almost all of the compounds 6a-h showed good to excellent activities against elastase enzyme more than the reference drug. Compounds 6d and 6b at 0.2 ± 0.0 μM and 0.2 ± 0.0 μM were found to most potent derivatives against elastase enzyme. Compound 6a exhibited prominent free radical scavenging activity. From the results of the biological activity, we infer that some derivatives can serve as lead molecules in pharmacology.
- Saeed, Aamer,Shahzad, Danish,Larik, Fayaz Ali,Channar, Pervaiz Ali,Mehfooz, Haroon,Abbas, Qamar,Hassan, Mubashir,Raza, Hussain,Seo, Sung-Yum,Shabbir, Ghulam
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p. 210 - 215
(2017/07/12)
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- Effective microwave synthesis of bioactive thieno[2,3-d]pyrimidines
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A series of novel 2-Amino-3-cyanothiophenes (2a-2j) were synthesized using heterogeneous base (K2CO3) supported Gewald reaction. Cyclization of 2a-j with formamide and urea in conventional heating as well as microwave irradiation gave thieno[2,3-d]pyrimidines (3a-3j) and thieno[2,3-d]pyrimidin-2(1H)-ones(4a-4j) respectively. The reaction rates were faster and yields were higher in the microwave conditions. The structures of the compounds were confirmed with elemental analysis, mass spectral analysis, FTIR, 1H NMR and 13C NMR techniques. All the synthesized compounds were subjected to antimicrobial activity (MIC) in vitro by broth dilution method and exhibited a moderate antimicrobial activity.
- Khatri, Taslimahemad T.,Shah, Viresh H.
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p. 3354 - 3358
(2017/05/22)
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- CYCLIC DIARYLBORON DERIVATIVES AS NLRP3 INFLAMMASOME INHIBITORS
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Inhibitor compounds are disclosed. The compounds are effective in the treatment of diseases or conditions in which interleukin 1 β activity is implicated. Methods of synthesis of the compounds, as well as pharmaceutical compositions comprising the compounds are also disclosed.
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Paragraph 00182
(2017/02/24)
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- Design, synthesis and antiproliferative activities evaluation of thiazolopyrimidines derivatives through biginelli reaction
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Background: Thiazolopyrimidines possessed their structural diversity and various biological activity. Up to date, thiazolopyrimidines derivatives have widespread applications in pharmaceutical fields. In this article, a series of thiazolopyrimidine derivatives were designed based on the lead compound structure in our previous studies. Methods: All the target compounds were synthesized with the coupling reaction, Biginelli reaction and “one-pot” aldol condensation. Their structures were identified by1H NMR,13C NMR spectra and HRMS. Antitumor activities of the target compounds were evaluated by MTT. Results: 25 new target compounds were synthesized and they primarily screened through testing their inhibitory rates against two human tumor cell lines and Compounds 15, 17, 20, 22, 40 exhibited more than 70% inhibitory rate against both MDA-MB-231 and K562. Further assessing their IC50 against five tumor cell lines, 15 and 22 show advantage over lead compound I in MDA-MB-231, K562 and PC-3. Conclusion: A series of thiazolopyrimidine derivatives were synthesized and the preliminary biological evaluation suggest that target compound 22 exhibited better antiproliferative activity against K562 than gossypol.
- Zhu, Pengju,Fu, Huansheng,Fang, Hao
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p. 1382 - 1390
(2017/12/28)
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- Novel 5-oxo-hexahydroquinoline derivatives: Design, synthesis, in vitro P-glycoprotein-mediated multidrug resistance reversal profile and molecular dynamics simulation study
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Overexpression of the efflux pump P-glycoprotein (P-gp) is one of the important mechanisms of multidrug resistance (MDR) in many tumor cells. In this study, 26 novel 5-oxo-hexahydroquinoline derivatives containing different nitrophenyl moieties at C4 and various carboxamide substituents at C3 were designed, synthesized and evaluated for their ability to inhibit P-gp by measuring the amount of rhodamine 123 (Rh123) accumulation in uterine sarcoma cells that overexpress P-gp (MES-SA/Dx5) using flow cytometry. The effect of compounds with highest MDR reversal activities was further evaluated by measuring the alterations of MES-SA/Dx5 cells’ sensitivity to doxorubicin (DXR) using MTT assay. The results of both biological assays indicated that compounds bearing 2-nitrophenyl at C4 position and compounds with 4-chlorophenyl carboxamide at C3 demonstrated the highest activities in resistant cells, while they were devoid of any effect in parental nonresistant MES-SA cells. One of the active derivatives, 5c, significantly increased intracellular Rh123 at 100 μM, and it also significantly reduced the IC50 of DXR by 70.1% and 88.7% at 10 and 25 μM, respectively, in MES-SA/Dx5 cells. The toxicity of synthesized compounds against HEK293 as a noncancer cell line was also investigated. All tested derivatives except for 2c compound showed no cytotoxicity. A molecular dynamics simulation study was also performed to investigate the possible binding site of 5c in complex with human P-gp, which showed that this compound formed 11 average H-bonds with Ser909, Thr911, Arg547, Arg543 and Ser474 residues of P-gp. A good agreement was found between the results of the computational and experimental studies. The findings of this study show that some 5-oxo-hexahydroquinoline derivatives could serve as promising candidates for the discovery of new agents for P-gp-mediated MDR reversal.
- Shahraki, Omolbanin,Edraki, Najmeh,Khoshneviszadeh, Mehdi,Zargari, Farshid,Ranjbar, Sara,Saso, Luciano,Firuzi, Omidreza,Miri, Ramin
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p. 407 - 418
(2017/02/26)
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- Acetyl aceotphenone amine preparation method of the compound
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The invention provides a preparation method of an acetoacetanilide compound. The method comprises the steps of performing diacetylation reaction on aniline compounds and diketene in an organic solvent under anaerobic conditions to obtain the acetoacetanilide compound. The acetoacetanilide compound is prepared under the anaerobic conditions; the acetoacetanilide compound prepared by using the method has a relatively high melting point, thereby being beneficial for applications of the acetoacetanilide compound. In addition, the acetoacetanilide compound prepared by using the method provided by the invention is not easy to agglomerate, and the preparation method of the acetoacetanilide compound, provided by the invention, is relatively low in energy consumption. Experimental results show that the melting point of the acetoacetanilide compound prepared by using the method provided by the invention is 82.5-103 DEG C.
- -
-
Paragraph 0051; 0052; 0054
(2017/02/24)
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- Synthesis and biofilm formation reduction of pyrazole-4-carboxamide derivatives in some Staphylococcus aureus strains
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The ability of several N-phenyl-1H-pyrazole-4-carboxamide derivatives and other pyrazoles opportunely modified at the positions 3, 4 and 5, to reduce the formation of the biofilm in some Staphylococcus aureus strains (ATCC 29213, ATCC 25923 and ATCC 6538) were investigated. All the tested compounds were able, although to a different extent, to reduce the biofilm formation of the three bacterial strains considered. Among these, the 1-(2,5-dichlorophenyl)-5-methyl-N-phenyl-1H-pyrazole-4-carboxamide 14 resulted as the best inhibitor of biofilm formation showing an IC50ranging from 2.3 to 32 μM, against all the three strains of S. aureus. Compound 14 also shows a good protective effect in vivo by improving the survival of wax moth larva (Galleria mellonella) infected with S. aureus ATCC 29213. These findings indicate that 14d is a potential lead compound for the development of new anti-virulence agents against S. aureus infections.
- Cascioferro, Stella,Maggio, Benedetta,Raffa, Demetrio,Raimondi, Maria Valeria,Cusimano, Maria Grazia,Schillaci, Domenico,Manachini, Barbara,Plescia, Fabiana,Daidone, Giuseppe
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-
- A convenient method for reduction dehalogenation of α-halocarbonyl compounds using benzenethiol in K+/CH3CN system
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Benzenethiol, as a reductive agent for the dehalogenation of various α-halocarbonyl compounds, is investigated in the K+/CH3CN system. The reaction affords the reduced compounds in high yields under mild reaction conditions, especially α-chlorocarbonyl compounds. Furthermore, the reaction performed under ultrasonic irradiation greatly shortens the reaction time.
- Dong, Wei-Li,Cai, Wen-Xi,Wu, Rui,Li, Zheng-Ming,Zhao, Wei-Guang,Liu, Xing-Hai
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p. 980 - 983
(2016/07/06)
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- [3 + 2]-Annulations of N-hydroxy allenylamines with nitrosoarenes: One-pot synthesis of substituted indole products
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In the presence of O2 and an IPrCuCl additive (5 mol %), [3 + 2]-annulation reactions of N-hydroxyaniline with nitrosobenzenes in cold toluene form isoxazolidin-5-ol derivatives. Heating the same reaction mixture with DBU in toluene affords highly functionalized indole products efficiently. This method provides short synthesis of several bioactive molecules including WIN 48098, WIN 53365, and JWH 015.
- Sharma, Pankaj,Liu, Rai-Shung
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p. 412 - 415
(2016/02/18)
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- Silver(I)-catalyzed tandem approach to β-oxo amides
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A facile and efficient AgI-catalytic approach is reported for the first time to synthesize β-oxo amides from β-oxo esters a with broad substrate scope in good to excellent yields. Crossover and in situ NMR studies confirmed that the reaction occurred through a new pathway and not by the traditional condensation reaction. The key advantages of this method are the readily available starting materials, the air-stable reaction, the simple protocol, and the environmental friendliness. A new, catalytic approach to the synthesis of β-oxo amides from β-oxo esters with a broad substrate scope in good to excellent yields was developed. In situ NMR spectroscopy and crossover experiments confirmed the reaction mechanism.
- Vandavasi, Jaya Kishore,Hsiao, Cheng-Tien,Hu, Wan-Ping,Boominathan, Siva Senthil Kumar,Wang, Jeh-Jeng
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supporting information
p. 3171 - 3177
(2015/05/13)
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- Multicomponent strategy to indeno[2,1- C ]pyridine and hydroisoquinoline derivatives through cleavage of carbon-carbon bond
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A concise and efficient three-component domino reaction has been developed for the synthesis of polyfunctionalized indenopyridine and hydroisoquinoline derivatives via the cleavage of a C-C bond under transition-metal-free conditions. This reaction provides facile access to complex nitrogen-containing heterocycles by simply mixing three common starting materials in EtOH in the presence of 20 mol % NaOH under microwave irradiation conditions.
- Feng, Xian,Wang, Jian-Jun,Xun, Zhan,Huang, Zhi-Bin,Shi, Da-Qing
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p. 1025 - 1033
(2015/01/30)
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- Discovery and Optimization of Novel, Selective Histone Methyltransferase SET7 Inhibitors by Pharmacophore- and Docking-Based Virtual Screening
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Histone methyltransferases are involved in various biological functions, and these methylation regulating enzymes' abnormal expression or activity has been noted in several human cancers. Within this context, SET domain-containing (lysine methyltransferase) 7 (SET7, also called KMT7, SETD7, SET9) is of increasing significance due to its diverse roles in biological functions and diseases, such as diabetes, cancers, alopecia areata, atherosclerotic vascular disease, HIV, and HCV. In this study, DC-S100, which was discovered by pharmacophore- and docking-based virtual screening, was identified as the hit compound of SET7 inhibitor. Structure-activity relationship (SAR) analysis was performed on analogs of DC-S100 and according to the putative binding mode of DC-S100, structure modifications were made to improve its activity. Of note, compounds DC-S238 and DC-S239, with IC50 values of 4.88 and 4.59 μM, respectively, displayed selectivity for DNMT1, DOT1L, EZH2, NSD1, SETD8, and G9a. Taken together, DC-S238 and DC-S239 can serve as leads for further investigation as SET7 inhibitors and the chemical toolkits for functional biology studies of SET7.
- Meng, Fanwang,Cheng, Sufang,Ding, Hong,Liu, Shien,Liu, Yan,Zhu, Kongkai,Chen, Shijie,Lu, Junyan,Xie, Yiqian,Li, Linjuan,Liu, Rongfeng,Shi, Zhe,Zhou, Yu,Liu, Yu-Chih,Zheng, Mingyue,Jiang, Hualiang,Lu, Wencong,Liu, Hong,Luo, Cheng
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p. 8166 - 8181
(2015/11/09)
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- Targeting dormant tuberculosis bacilli: Results for molecules with a novel pyrimidone scaffold
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Our inability to completely control TB has been due in part to the presence of dormant mycobacteria. This also renders drug regimens ineffective and is the prime cause of the appearance of drug-resistant strains. In continuation of our efforts to develop novel antitubercular agents that especially target dormant mycobacteria, a set of 55 new compounds belonging to the pyrimidone class were designed on the basis of CoMFA and CoMSIA studies, and these were synthesized and subsequently tested against both the dormant and virulent BCG strain of M. tuberculosis. Some novel compounds have been identified which selectively inhibit the dormant tuberculosis bacilli with significantly low IC50 values. This study reports the second molecule after TMC-207, having the ability to inhibit tuberculosis bacilli exclusively in its dormant phase. The synthesis was accomplished by a modified multicomponent Biginelli reaction. A classification model was generated using the binary QSAR approach - recursive partitioning (RP) to identify structural characteristics related to the activity. Physicochemical, structural, topological, connectivity indices, and E-state key descriptors were used for generation of the decision tree. The decision tree could provide insights into structure-activity relationships that will guide the design of more potent inhibitors. This paper reports the second molecule after TMC-207, with the ability to inhibit tuberculosis bacilli in its dormant phase. The paper reports molecules with a novel Pyrimidone Scaffold, the synthesis of which was accomplished with a modified multi-component Biginelli reaction. A classification model was generated using recursive partitioning (RP) technique to identify structural characteristics of the molecules with their varying activities.
- Joshi, Rohit R.,Barchha, Avinash,Khedkar, Vijay M.,Pissurlenkar, Raghuvir R. S.,Sarkar, Sampa,Sarkar, Dhiman,Joshi, Rohini R.,Joshi, Ramesh A.,Shah, Anamik K.,Coutinho, Evans C.
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p. 201 - 207
(2015/01/30)
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- Cu-catalyzed aerobic oxidative cyclizations of 3-N-hydroxyamino-1,2-propadienes with alcohols, thiols, and amines to form α-O-, S-, and N-substituted 4-methylquinoline derivatives
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A one-pot, two-step synthesis of α-O-, S-, and Nsubstituted 4-methylquinoline derivatives through Cu-catalyzed aerobic oxidations of N-hydroxyaminoallenes with alcohols, thiols, and amines is described. This reaction sequence involves an initial oxidation of N-hydroxyaminoallenes with NuH (Nu = OH, OR, NHR, and SR) to form 3-substituted 2-en-1-ones, followed by Bronsted acid catalyzed intramolecular cyclizations of the resulting products. Our mechanistic analysis suggests that the reactions proceed through a radical-type mechanism rather than a typical ni-trone-intermediate route. The utility of this new Cu-catalyzed reaction is shown by its applicability to the synthesis of several 2-amino-4-methylquinoline derivatives, which are known to be key precursors to several bioactive molecules.
- Sharma, Pankaj,Liu, Rai-Shung
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supporting information
p. 4590 - 4594
(2015/03/18)
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- An efficient green protocol for the preparation of acetoacetamides and application of the methodology to a one-pot synthesis of Biginelli dihydropyrimidines. Expansion of dihydropyrimidine topological chemical space
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The present study describes the preparation of N-aryl-(15) and N-alkyl-(17) acetoacetamides, in good to excellent yields, using both conventional and microwave heating, by reaction of amine derivatives (14 and 16) with 2,2,6-trimethyl-4H-1,3-dioxin-4-one (TMD, 12) in aqueous medium. The acetoacetamides were used to prepare novel Biginelli dihydropyrimidine derivatives. The introduction of the amino acid derivatives potentially allows for the exploration of new structural complexity and topologically diversifies the chemical space occupied by this versatile chemical scaffold.
- Gama, Fernando H. S.,De Souza, Rodrigo O. M. A.,Garden, Simon J.
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p. 70915 - 70928
(2015/09/08)
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- LIGAND-CONTROLLED C(SP3)-H ARYLATION AND OLEFINATION IN SYNTHESIS OF UNNATURAL CHIRAL ALPHA AMINO ACIDS
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The use of ligands to tune the reactivity and selectivity of transition metal-catalysts for C(-sp3)-H bond functionalization is a central challenge in synthetic organic chemistry. Herein, we report a rare example of catalyst-controlled C(sp3)-H arylation using pyridine and quinoline derivatives: the former promotes exclusive monoarylation, whereas the latter activates the catalyst further to achieve diarylation. Successive application of these ligands enables the sequential diarylation of a methyl group in an alanine derivative with two different aryl iodides, affording a wide range of β-Ar-p-Ar ' -cc-amino acids with excellent levels of diastereoselectivity (d.r. > 20:1). Both configurations of the β-chiral center can be accessed by choosing the order in which the aryl groups are installed. The use of a quinoline derivative as a ligand also enables C(sp3)-H olefination of a protected alanine.
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-
Page/Page column 150; 151
(2015/10/05)
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- Facile eco-friendly synthesis of novel chromeno[4,3-b]pyridine-2,5-diones and evaluation of their antimicrobial and antioxidant properties
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Rapid and facileaccess to novel chromeno[4,3-b]pyridine-2,5-dione derivatives was achieved by a mild base catalysed reaction of 4-chloro-3-formylcoumarin and acetoacetamides in PEG-300 as recyclable solvent. The compounds were evaluated for their antimicrobial activities against 3 Gram-positive and 3 Gram-negative bacteria (Staphylococcus epidermis, Vibrio parahaemolyticus, Bacillus subtilis, Escherichia coli, Staphylococcus aureus and Klebsiella pneumonia) with Cefotaxime control. They were further subjected to antioxidant studies using DPPH test with ascorbic acid control. While compounds 5d and 5k showed promising broad spectrum antibacterial properties against all the evaluated bacteria, compound 5g exhibited good antioxidant properties. Indian Academy of Sciences.
- Jaggavarapu, Satyanarayana Reddy,Kamalakaran, Anand Solomon,Jalli, Ventkata Prasad,Gangisetty, Sravan Kumar,Ganesh, Munusswamy Ramanujam,Gaddamanugu, Gopikrishna
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p. 187 - 195
(2014/04/03)
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- Facile eco-friendly synthesis of novel chromeno[4,3-b]pyridine-2,5-diones and evaluation of their antimicrobial and antioxidant properties
-
Rapid and facile access to novel chromeno[4,3-b]pyridine-2,5-dione derivatives was achieved by a mild base catalysed reaction of 4-chloro-3-formylcoumarin and acetoacetamides in PEG-300 as recyclable solvent. The compounds were evaluated for their antimicrobial activities against 3 Gram-positive and 3 Gram-negative bacteria (Staphylococcus epidermis, Vibrio parahaemolyticus, Bacillus subtilis, Escherichia coli, Staphylococcus aureus and Klebsiella pneumonia) with Cefotaxime control. They were further subjected to antioxidant studies using DPPH test with ascorbic acid control. While compounds 5d and 5k showed promising broad spectrum antibacterial properties against all the evaluated bacteria, compound 5g exhibited good antioxidant properties. [Figure not available: see fulltext.]
- Jaggavarapu, Satyanarayana Reddy,Kamalakaran, Anand Solomon,Jalli, Ventkata Prasad,Gangisetty, Sravan Kumar,Ganesh, Munusswamy Ramanujam,Gaddamanugu, Gopikrishna
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p. 187 - 195
(2016/02/26)
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- Ligand-enabled γ-C-H olefination and carbonylation: Construction of β-quaternary carbon centers
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Monoselective γ-C-H olefination and carbonylation of aliphatic acids has been accomplished by using a combination of a quinoline-based ligand and a weakly coordinating amide directing group. The reaction provides a new route for constructing richly functionalized all-carbon quaternary carbon centers at the β-position of aliphatic acids.
- Li, Suhua,Chen, Gang,Feng, Chen-Guo,Gong, Wei,Yu, Jin-Quan
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supporting information
p. 5267 - 5270
(2014/05/06)
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- Catalyst-free rapid synthesis of benzo[4,5]imidazo[1,2-a]-pyrimidine-3- carboxamides via four-component coupling in one pot
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Abstract: A new class of fused tricyclic benzo[4,5]imidazo[1,2-a]- pyrimidine-3-carboxamide derivatives was synthesized via an environmentally benign one pot sequential four-component condensation reaction of an amine, 2,2,6-trimethyl-4H-1,3-dioxin-4-one, an aldehyde and 1H-benzo[d]imidazol-2-amine without using catalyst in good yields.
- Shaabani, Ahmad,Seyyedhamzeh, Mozhdeh,Ganji, Nasim,Ng, Seik Weng
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p. 481 - 487
(2014/04/03)
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- One-pot synthesis of 3-hydroxyquinolin-2(1 H)-ones from N-phenylacetoacetamide via PhI(OCOCF3)2-mediated α-hydroxylation and H2SO4-promoted intramolecular cyclization
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A clean, one-pot synthesis of the biologically important 3-hydroxyquinolin-2(1H)-one compounds has been realized from the readily available N-phenylacetoacetamide derivatives through a PhI(OCOCF 3)2-mediated α-hydroxylation and a H 2SO4-promoted intramolecular condensation. The hydroxyl group in the generated α-hydroxylated intermediate can be well tolerated in the second H2SO4-promoted cyclization step.
- Yuan, Yucheng,Yang, Rui,Zhang-Negrerie, Daisy,Wang, Junwei,Du, Yunfei,Zhao, Kang
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p. 5385 - 5392
(2013/07/26)
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- Synthesis and in vitro anticancer and antitubercular activity of diarylpyrazole ligated dihydropyrimidines possessing lipophilic carbamoyl group
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A series of dihydropyrimidine derivatives were synthesized by utilizing Biginelli reaction and evaluated for their in vitro anticancer activity against MCF-7 human breast cancer (HBC) cell line using sulforhodamine B (SRB) assay and antitubercular activity against Mycobacterium tuberculosis (MTB) H 37Rv using Microplate Alamar Blue Assay (MABA). Compounds 13p, 13t were exhibited 70.6% and 63.7% of HBC cell growth inhibition at 10 μM concentration. Interestingly compound 13p was also found to be the most potent in the series against MTB H37Rv with MIC value of 0.125 μg/mL.
- Yadlapalli, Rama Krishna,Chourasia,Vemuri, Kiranmayi,Sritharan, Manjula,Perali, Ramu Sridhar
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supporting information; experimental part
p. 2708 - 2711
(2012/05/20)
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- Synthesis, antibacterial and antimycobacterial activities of some new 4-aryl/heteroaryl-2,6-dimethyl-3,5-bis-N-(aryl)-carbamoyl-1,4-dihydropyridines
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A novel class of 4-aryl/heteroaryl-2,6-dimethyl-3,5-bis-N-(phenyl/ substituted phenyl)-carbamoyl-1,4-dihydropyridines has been synthesized by simple, economical and eco-friendly, modified Hantzsch condensation reaction making use of N-arylacetoacetamides, aryl or heteroaryl aldehydes and ammonium acetate. The newly synthesized compounds were characterized by their spectral (IR, 1H NMR, Mass), elemental analyses data and evaluated for in vitro antitubercular activity against Mycobacterium tuberculosis H 37Rv ATCC 27294 and antibacterial activity against different Gram +ve and Gram -ve bacteria. The preliminary screening results revealed that some of the compounds possess promising antimicrobial activity. Amongst the new series of compounds, 6m containing pyrrolyl and 4-methylphenyl groups and 6r possessing 2-pyridyl and 2-methylphenyl groups were found to exhibit a significant antitubercular activity (MIC = 12.5-25 μg/mL) in comparison with the first line drug pyrazinamide.
- Sirisha, Kalam,Bikshapathi, Darna,Achaiah, Garlapati,Reddy, Vanga Malla
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experimental part
p. 1564 - 1571
(2011/05/06)
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- Straightforward access to (imidazol-2-yl)acetates by reaction of 2-unsubstituted imidazole 3-oxides with dimethyl acetylenedicarboxylate
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A new method for the preparation of 1,4,5-trisubstituted (imidazol-2-yl)acetates, based on the reaction of the corresponding imidazole 3-oxides with dimethyl acetylenedicarboxylate (DMAD) is described. Formation of the products is rationalized by a formal 1,3-dipolar cycloaddition and subsequent oxaloyl cleavage. 1,4,5-Trisubstituted imidazole 3-oxides bearing an electron-withdrawing substituent at C(4), easily react with dimethyl acetylenedicarboxylate (DMAD), yielding the corresponding oxobutanoates, which subsequently, in a one-pot procedure undergo hydrolysis through an "oxaloyl cleavage" mode. New (imidazol-2-yl)acetates were isolated in high yields. Copyright
- Mlostoń, Grzegorz,Jasiński, Marcin,Heimgartner, Heinz
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scheme or table
p. 2542 - 2547
(2011/05/16)
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- Pd-catalyzed carbonylation of diazo compounds at atmospheric pressure: A catalytic approach to ketenes
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The carbonylation of carbenes through catalytic cycles is highly desirable due to the importance of ketene-mediated reactions in organic synthesis. In this investigation, a highly efficient and mild catalytic approach toward ketene intermediates has been developed based on Pd-catalyzed carbonylation of diazo compounds with CO. When α-diazocarbonyl compounds or N-tosylhydrazone salts are heated in the presence of a palladium catalyst under atmospheric pressure of CO, ketene intermediates are formed in situ, where they undergo further reactions with various nucleophiles such as alcohols, amines, or imines. The Pd-catalyzed tandem carbonylation-Staudinger cycloaddition gives β-lactam derivatives in good yields with excellent trans diastereoselectivity. The results from DFT calculation on the reaction mechanism suggest that Pd is involved in the [2 + 2] cycloaddition process and affects the diastereoselectivity of the β-lactam products by assisting isomerization of the addition intermediate. On the other hand, the acylketenes generated from the Pd-catalyzed carbonylation of α-diazoketones react with imines in a formal [4 + 2] cycloaddition manner to afford 1,3-dioxin-4-one derivatives. This straightforward carbonylation provides a new approach toward highly efficient catalytic generation of ketene species under mild conditions.
- Zhang, Zhenhua,Liu, Yiyang,Ling, Lin,Li, Yuxue,Dong, Yian,Gong, Mingxing,Zhao, Xiaokun,Zhang, Yan,Wang, Jianbo
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supporting information; experimental part
p. 4330 - 4341
(2011/06/21)
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- Ru-catalyzed asymmetric hydrogenation of 3-oxoglutaric acid derivatives via solvent-assisted pinpoint recognition of carbonyls in close chemical propinquity
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Upon comparison of hydrogenation rates of various β-ketocarboxylic acid derivatives, β-ketoamides were found to be hydrogenated slightly faster than β-ketoesters in EtOH in the presence of [RuCl(benzene)(S)- SunPhos]Cl at 70 °C with 20 bar of hydrogen. In THF these differences were so sharpened that β-ketoamides were hydrogenated even faster than in EtOH while the esters were extremely slow. Based on these findings, a series of 3-oxoglutaric acid derived with ester and amide moieties on the two ends were hydrogenated to 3-hydroxyl products with high enantioselectivities.
- Li, Wanfang,Ma, Xin,Fan, Weizheng,Tao, Xiaoming,Li, Xiaoming,Xie, Xiaomin,Zhang, Zhaoguo
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supporting information; experimental part
p. 3876 - 3879
(2011/10/01)
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- Synthesis of Pyridin-2(1H)-one derivatives: Temperature-dependent selectivity
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Two alternative methods for the synthesis of biologically important pyridin-2(1H)-one derivatives have been developed. The behavior of enamine 1 with aromatic amines in an aqueous solution of HCl resulted in the formation of substituted enamines 2a-f at ambient temperature. The obtained product enamines 2a-f, upon treatment with 2,2,6-trimethyl-4H-1,3-dioxin-4-one, generated pyridin-2(1H)-one derivatives 5a-f along with the unwanted side products 8a-f. However, the exclusive formation of pyridin-2(1H)-one derivatives 5a-f was achieved when starting from β-enaminones 3a-f, which were synthesized successfully from enamine 1 and aromatic amines at elevated temperatures. Compounds 2 and 3 have been used as precursors in the synthesis of pyridin-2(1H)-one derivatives. Temperature-dependent reaction diversity was observed for enamine 1 and the exclusive formation of pyridin-2(1H)-one derivatives 5 was possible.
- Chikhalikar, Sandip,Bhawe, Vijay,Jachak, Madhukar,Ghagare, Maruti
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experimental part
p. 6085 - 6091
(2011/12/02)
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- Synthesis and selected transformations of 3-oxido-1H-imidazole-4- carboxamides
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An efficient synthesis of new N-alkyl- and N-aryl-3-oxido-1H-imidazole-4- carboxamides based on exploration of inexpensive, commercially available ethyl acetoacetate, paraformaldehyde and primary amines is described. Representative compounds were tested in selected transformations, such as 'sulfur-transfer reaction' leading to imidazole-2-thiones and isomerization to corresponding imidazol-2-ones. Strong intramolecular hydrogen bonding via the N-oxide function results in the reduced reactivity of 3-oxido-1H-imidazole-4-carboxamides in both reactions. Moreover, the palladium catalyzed C(2)-arylation of imidazole ring as well as azide-alkyne [3+2] cycloaddition using the N-propargyl substituted 4-carboxamide derived from an imidazole 3-oxide as a dipolarophile, were also studied.
- Mloston, Grzegorz,Jasinski, Marcin
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experimental part
p. 871 - 885
(2011/05/19)
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- Naftifine-analogues as anti-Trypanosoma cruzi agents
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Chagas disease represents a relevant health problem in Central and South America. The first line of treatment is Nifurtimox and Benznidazole which have a great deal of disadvantages that demands the rapid generation of therapeutic alternatives. Based in our research on aza-thiaheterocycles as anti-Trypanosoma cruzi agents we identified pharmacophores that act through oxidative stress. Here, we describe the synthesis and the activity of new containing bioactive-heterocycles analogues of naftifine as potential T. cruzi membrane sterol biosynthesis inhibitors. Benzimidazole 1,3-dioxides (11 and 13) and quinoxaline 1,4-dioxides (22 and 23) displayed excellent parasite/mammal selectivity indexes. Analysis of the free sterols from parasite incubated with the compounds showed that any of them are able to accumulate squalene suggesting that in the anti-T. cruzi mechanism of action is not involved the inhibition of sterol biosynthesis. Some derivatives were also tested as antifungal agents. The results obtained in the present work open potential therapeutic possibilities of new compounds for these infectious diseases.
- Gerpe, Alejandra,Boiani, Lucía,Hernández, Paola,Sortino, Maximiliano,Zacchino, Susana,González, Mercedes,Cerecetto, Hugo
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supporting information; experimental part
p. 2154 - 2164
(2010/09/11)
-