- Discovery of Novel Tacrine-Pyrimidone Hybrids as Potent Dual AChE/GSK-3 Inhibitors for the Treatment of Alzheimer's Disease
-
Based on a multitarget strategy, a series of novel tacrine-pyrimidone hybrids were identified for the potential treatment of Alzheimer's disease (AD). Biological evaluation results demonstrated that these hybrids exhibited significant inhibitory activities toward acetylcholinesterase (AChE) and glycogen synthase kinase 3 (GSK-3). The optimal compound 27g possessed excellent dual AChE/GSK-3 inhibition both in terms of potency and equilibrium (AChE: IC50 = 51.1 nM; GSK-3β: IC50 = 89.3 nM) and displayed significant amelioration on cognitive deficits in scopolamine-induced amnesia mice and efficient reduction against phosphorylation of tau protein on Ser-199 and Ser-396 sites in glyceraldehyde (GA)-stimulated differentiated SH-SY5Y cells. Furthermore, compound 27g exhibited eligible pharmacokinetic properties, good kinase selectivity, and moderate neuroprotection against GA-induced reduction in cell viability and neurite damage in SH-SY5Y-derived neurons. The multifunctional profiles of compound 27g suggest that it deserves further investigation as a promising lead for the prospective treatment of AD.
- Yao, Hong,Uras, Giuseppe,Zhang, Pengfei,Xu, Shengtao,Yin, Ying,Liu, Jie,Qin, Shuai,Li, Xinuo,Allen, Stephanie,Bai, Renren,Gong, Qi,Zhang, Haiyan,Zhu, Zheying,Xu, Jinyi
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p. 7483 - 7506
(2021/06/28)
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- Expedient discovery for novel antifungal leads: 1,3,4-Oxadiazole derivatives bearing a quinazolin-4(3H)-one fragment
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Developing novel fungicide candidates are intensively promoted by the rapid emergences of resistant fungi that outbreak on agricultural production. Aiming to discovery novel antifungal leads, a series of 1,3,4-oxadiazole derivatives bearing a quinazolin-4(3H)-one fragment were constructed for evaluating their inhibition effects against phytopathogenic fungi in vitro and in vivo. Systematically structural optimizations generated the bioactive molecule I32 that was identified as a promising inhibitor against Rhizoctonia solani with the in vivo preventative effect of 58.63% at 200 μg/mL. The observations that were captured by scanning electron microscopy and transmission electron microscopy demonstrated that the bioactive molecule I32 could induce the sprawling growth of hyphae, the local shrinkage and rupture on hyphal surfaces, the extreme swelling of vacuoles, the striking distortions on cell walls, and the reduction of mitochondria numbers. The above results provided an indispensable complement for the discovery of antifungal lead bearing a quinazolin-4(3H)-one and 1,3,4-oxadiazole fragment.
- Chai, Jianqi,Chen, Min,Jin, Fei,Kong, Xiangyi,Wang, Xiaobin,Xue, Wei,Yang, Chunlong
-
-
- Monitoring intracellular pH fluctuation with an excited-state intramolecular proton transfer-based ratiometric fluorescent sensor
-
Intracellular pH is a key parameter related to various biological and pathological processes. In this study, a ratiometric pH fluorescent sensor ABTT was developed harnessing the amino-type excited-state intramolecular proton transfer (ESIPT) process. Relying on whether the ESIPT proceeds normally or not, ABTT exhibited the yellow fluorescence in acidic media, or cyan fluorescence in basic condition. According to the variation, ABTT behaved as a promising sensor which possessed fast and reversible response to pH change without interference from the biological substances, and exported a steady ratiometric signal (I478/I546). Moreover, due to the ESIPT effect, large Stokes shift and high quantum yield were also exhibited in ABTT. Furthermore, ABTT was applied for monitoring the pH changes in living cells and visualizing the pH fluctuations under oxidative stress successfully. These results elucidated great potential of ABTT in understanding pH-dependent physiological and pathological processes.
- Feng, Bin,Zhu, Yingli,Wu, Jiaxin,Huang, Xueyan,Song, Rong,Huang, Liu,Feng, Xueping,Zeng, Wenbin
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p. 3057 - 3060
(2021/04/12)
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- Preparation method of 5-chloro-2-aminobenzoic acid intermediate
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The invention discloses a preparation method of 5-chloro-2-aminobenzoic acid, and belongs to the technical field of organic synthesis, the preparation method specifically comprises the following steps: dissolving 2, 5-dichlorotoluene in a solvent, adding an oxidant while stirring, heating to 50-80 DEG C, carrying out heat preservation reaction for 3-6 hours, recovering the organic solvent after the reaction is finished, adding water, filtering while hot, and adjusting the pH value of the filtrate to 2 by using hydrochloric acid, obtaining 2, 5-dichlorobenzoic acid through cooling, crystallization and filtering, adding 2, 5-dichlorobenzoic acid into an organic solvent to be dissolved, addign a metal catalyst, alkali and an ammonia source, heating the mixture to 70-150 DEG C and then performing a heat preservation reaction for 8-15 h, performing reduced pressure distillation after the reaction is finished, and obtaining 5-chloro-2-aminobenzoic acid. A new path for synthesizing 5-chloro-2-aminobenzoic acid is designed, the preparation method is simple, easy to operate, low in cost and environmentally friendly, and N, N-dimethylglycine is added in the ammoniation reaction process, so that the temperature of the ammoniation reaction can be reduced, the reaction time can be shortened, and the reaction yield can be increased.
- -
-
Paragraph 0017-0020
(2021/08/11)
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- Selenium-catalyzed intramolecular atom- And redox-economical transformation ofo-nitrotoluenes into anthranilic acids
-
Anthranilic acids (AAs) are significant basic chemicals used in pharmaceuticals, agrochemicals, dyes, fragrances,etc. Superfluous steps are always involved in obtaining AAs. Herein, we demonstrate a straightforward strategy to transform abundanto-nitrotoluenes into biologically and pharmaceutically significant AAs without any extra reductants, oxidants and protecting groups. Various sensitive groups, such as halogens, sulfide, aldehyde, pyridines, quinolines,etc., can be tolerated in this transformation. A hundred-gram-scale operation is realized efficiently with almost quantitative selenium recycling. Further mechanistic studies and DFT calculations disclosed the proposed atom-exchange processes and the key roles of the selenium species.
- Jiang, Xuefeng,Li, Yiming,Lin, Zhenyang,Wang, Yuhong,Yang, Tilong
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supporting information
p. 2986 - 2991
(2021/05/05)
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- Anthranilic acid and derivatives thereof as well as synthesis method and application thereof
-
In the reaction solvent, o-methyl (hetero) aryl nitro compound is taken as a reaction raw material and is used for water. The anthranilic acid and its derivatives are synthesized by the action of a catalyst, a base and an additive. The synthetic method has the advantages of cheap and easily available raw materials, simple reaction operation, high yield and excellent functional group tolerance, and provides a simple and efficient method for synthesizing o-aminobenzoic acid which is widely used in the aspects of dyes, medicines, pesticides, spices and the like. The invention further discloses the anthranilic acid and derivatives and application thereof, and has a wide application prospect.
- -
-
Paragraph 0080-0082
(2021/09/15)
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- Br?nsted Acid-Catalyzed Asymmetric Ring-Closing Alkylation of Inert N-substituted Pyrroles with α, β-Unsaturated Ketones
-
A Chiral Br?nsted acid catalyzed asymmetric intramolecular ring-closing alkylation of inert pyrroles with α, β-unsaturated ketones has been developed. This approach gave a wide range of 4-phenyl-4,5-dihydro-6H-benzo[f]pyrrolo[1,2-a]azepin-6-ones in high yields with good enantioselectivities under mild reaction conditions. (Figure presented.).
- Wei, Zhao,Zhang, Jinlong,Yang, Huameng,Jiang, Gaoxi
-
supporting information
p. 3694 - 3697
(2019/07/12)
-
- Functionalization of Quinazolin-4-ones Part 3: Synthesis, Structures Elucidation, DNA-PK, PI3K, and Cytotoxicity of Novel 8-Aryl-2-morpholino-quinazolin-4-ones
-
A series of novel 8-aryl-2-morpholino quinazolines (11a–n, 12a–d, 14a–f, and 15) were synthesized from the precursor 2-thioxo quinazolin-4-ones 8. The 8-aryl-2-morpholino quinazolines compounds were assayed for DNA-PK and PI3K. All compounds showed low DNA-PK % inhibition activity at 10?μM compound concertation, and the most active was 8-(dibenzo[b,d]thiophen-4-yl) 12d with 38% inhibition. Similar pattern of PI3K α, β, γ, and δ isoforms inhibition activity at 10?μM were observed. The most active isoform was PI3K δ of 41% inhibition for 8-(dibenzo[b,d]furan-4-yl) compound 11. Most compounds were less active than expected in spite of the strong structural resemblance to known inhibitors (NU7441, 3, 4, and 6). Loss of activity could be attributed to the tautomerization to the aromatic enol (4-OH), which could specify that the important functional group for the activity is the 4-carbonyl (C=O) group. Alternatively, the aromatization of the pyrimidine heterocyclic ring could alter the conformation, and thus binding site, of the 2-morpholine ring, which could reduce the compound-receptor hydrogen bonding to the morpholine 4-oxygen. Selected compounds displayed appreciable cytotoxicity with 6-chloro-8-(dibenzo[b,d]thiophen-4-yl)-2-morpholinoquinazolin-4(1H)-one 11j exhibiting the greatest activity with an IC50 of 9.95?μM. Therefore, the mechanism of the cytotoxicity of compound 11j were not through DNA-PK or PI3K inhibition activity.
- Heppell, Jacob T.,Islam, Md. Amirul,McAlpine, Shelli R.,Al-Rawi, Jasim M. A.
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p. 124 - 141
(2018/12/11)
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- Molecular Hybridization-Inspired Optimization of Diarylbenzopyrimidines as HIV-1 Nonnucleoside Reverse Transcriptase Inhibitors with Improved Activity against K103N and E138K Mutants and Pharmacokinetic Profiles
-
Molecular hybridization is a powerful strategy in drug discovery. A series of novel diarylbenzopyrimidine (DABP) analogues were developed by the hybridization of FDA-approved drugs etravirine (ETR) and efavirenz (EFV) as potential HIV-1 nonnucleoside reverse transcriptase inhibitors (NNRTIs). Substituent modifications resulted in the identification of new DABPs with the combination of the strengths of the two drugs, especially compound 12d, which showed promising activity toward the EFV-resistant K103N mutant. 12d also had a favorable pharmacokinetic (PK) profile with liver microsome clearances of 14.4 μL/min/mg (human) and 33.2 μL/min/mg (rat) and an oral bioavailability of 15.5% in rat. However, its activity against the E138K mutant was still unsatisfactory; E138K is the most prevalent NNRTI resistance-associated mutant in ETR treatment. Further optimizations resulted in a highly potent compound (12z) with no substituents on the phenyl ring and a 2-methyl-6-nitro substitution pattern on the 4-cyanovinyl-2,6-disubstitued phenyl motif. The antiviral activity of this compound was much higher than those of ETR and EFV against the WT, E138K, and K103N variants (EC50 = 3.4, 4.3, and 3.6 nM, respectively), and the cytotoxicity was decreased while the selectivity index (SI) was increased. In particular, this compound exhibited acceptable intrinsic liver microsome stability (human, 34.5 μL/min/mg; rat, 33.2 μL/min/mg) and maintained the good PK profile of its parent compound EFV and showed an oral bioavailability of 16.5% in rat. Molecular docking and structure-activity relationship (SAR) analysis provided further insights into the binding of the DABPs with HIV-1 reverse transcriptase and provided a deeper understanding of the key structural features responsible for their interactions.
- Han, Sheng,Sang, Yali,Wu, Yan,Tao, Yuan,Pannecouque, Christophe,De Clercq, Erik,Zhuang, Chunlin,Chen, Fen-Er
-
-
- Structure and biocatalytic scope of thermophilic flavin-dependent halogenase and flavin reductase enzymes
-
Flavin-dependent halogenase (Fl-Hal) enzymes have been shown to halogenate a range of synthetic as well as natural aromatic compounds. The exquisite regioselectively of Fl-Hal enzymes can provide halogenated building blocks which are inaccessible using standard halogenation chemistries. Consequently, Fl-Hal are potentially useful biocatalysts for the chemoenzymatic synthesis of pharmaceuticals and other valuable products, which are derived from haloaromatic precursors. However, the application of Fl-Hal enzymes, in vitro, has been hampered by their poor catalytic activity and lack of stability. To overcome these issues, we identified a thermophilic tryptophan halogenase (Th-Hal), which has significantly improved catalytic activity and stability, compared with other Fl-Hal characterised to date. When used in combination with a thermostable flavin reductase, Th-Hal can efficiently halogenate a number of aromatic substrates. X-ray crystal structures of Th-Hal, and the reductase partner (Th-Fre), provide insights into the factors that contribute to enzyme stability, which could guide the discovery and engineering of more robust and productive halogenase biocatalysts.
- Menon, Binuraj R. K.,Latham, Jonathan,Dunstan, Mark S.,Brandenburger, Eileen,Klemstein, Ulrike,Leys, David,Karthikeyan, Chinnan,Greaney, Michael F.,Shepherd, Sarah A.,Micklefield, Jason
-
supporting information
p. 9354 - 9361
(2016/10/13)
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- A Structure-Guided Switch in the Regioselectivity of a Tryptophan Halogenase
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Flavin-dependent halogenases are potentially useful biocatalysts for the regioselective halogenation of aromatic compounds. Haloaromatic compounds can be utilised in the synthesis and biosynthesis of pharmaceuticals and other valuable products. Here we report the first X-ray crystal structure of a tryptophan 6-halogenase (SttH), which enabled key residues that contribute to the regioselectivity in tryptophan halogenases to be identified. Structure-guided mutagenesis resulted in a triple mutant (L460F/P461E/P462T) that exhibited a complete switch in regioselectivity; with the substrate 3-indolepropionate 75 % 5-chlorination was observed with the mutant in comparison to 90 % 6-chlorination for the wild-type SttH. This is the first clear example of how regiocomplementary halogenases can be created from a single parent enzyme. The biocatalytic repertoire of SttH was also expanded to include a range of indolic and non-indolic substrates.
- Shepherd, Sarah A.,Menon, Binuraj R. K.,Fisk, Heidi,Struck, Anna-Winona,Levy, Colin,Leys, David,Micklefield, Jason
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p. 821 - 824
(2016/05/19)
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- Structure–activity relationship studies of benzyl-, phenethyl-, and pyridyl-substituted tetrahydroacridin-9-amines as multitargeting agents to treat Alzheimer's disease
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A library of substituted tetrahydroacridin-9-amine derivatives were designed, synthesized, and evaluated as dual cholinesterase and amyloid aggregation inhibitors. Compound 8e (N-(3,4-dimethoxybenzyl)-1,2,3,4-tetrahydroacridin-9-amine) was identified as a potent inhibitor of butyrylcholinesterase (BuChE IC50?=?20?nm; AChE IC50?=?2.2?μm) and was able to inhibit amyloid aggregation (40% inhibition at 25?μm). Compounds 9e (6-chloro-N-(3,4-dimethoxybenzyl)-1,2,3,4-tetrahydroacridin-9-amine, AChE IC50?=?0.8?μm; BuChE IC50?=?1.4?μm; Aβ-aggregation inhibition?=?75.7% inhibition at 25?μm) and 11b (6-chloro-N-(3,4-dimethoxyphenethyl)-1,2,3,4-tetrahydroacridin-9-amine, AChE IC50?=?0.6?μm; BuChE IC50?=?1.9?μm; Aβ-aggregation inhibition?=?85.9% inhibition at 25?μm) were identified as the best compounds with dual cholinesterase and amyloid aggregation inhibition. The picolylamine-substituted compound 12c (6-chloro-N-(pyridin-2-ylmethyl)-1,2,3,4-tetrahydroacridin-9-amine) was the most potent AChE inhibitor (IC50?=?90?nm). These investigations demonstrate the utility of 3,4-dimethoxyphenyl substituent as a novel pharmacophore possessing dual cholinesterase inhibition and anti-Aβ-aggregation properties that can be used in the design and development of small molecules with multitargeting ability to treat Alzheimer's disease.
- Osman, Wesseem,Mohamed, Tarek,Sit, Victor Munsing,Vasefi, Maryam S.,Beazely, Michael A.,Rao, Praveen P. N.
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p. 710 - 723
(2016/10/25)
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- Extending the biocatalytic scope of regiocomplementary flavin-dependent halogenase enzymes
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Flavin-dependent halogenases are potentially valuable biocatalysts for the regioselective halogenation of aromatic compounds. These enzymes, utilising benign inorganic halides, offer potential advantages over traditional non-enzymatic halogenation chemistry that often lacks regiocontrol and requires deleterious reagents. Here we extend the biocatalytic repertoire of the tryptophan halogenases, demonstrating how these enzymes can halogenate a range of alternative aryl substrates. Using structure guided mutagenesis we also show that it is possible to alter the regioselectivity as well as increase the activity of the halogenases with non-native substrates including anthranilic acid; an important intermediate in the synthesis and biosynthesis of pharmaceuticals and other valuable products. This journal is
- Shepherd, Sarah A.,Karthikeyan, Chinnan,Latham, Jonathan,Struck, Anna-Winona,Thompson, Mark L.,Menon, Binuraj R. K.,Styles, Matthew Q.,Levy, Colin,Leys, David,Micklefield, Jason
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p. 3454 - 3460
(2015/05/27)
-
- Synthesis of novel quinazolinone derivatives with methyl (E)-2-(3-methoxy)acrylate moiety
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A new series of quinazolinone derivatives with methyl (E)-2-(3-methoxy) acrylate moiety have been designed and synthesized. All target compounds had been identified by 1H NMR spectrum, IR spectrum and HR-MS (high resolution mass spectrum). Three target compounds (10a, 10e, 10h) were chosen to preliminarily test the antibacterial activities, the results showed that all three target compounds exhibited antibacterial activities against three bacterial strains (Proteobacteria, Salmonella, Colibacillus).
- Dong, Kui-Kui,Zhou, Hua-Hong,Guo, A-Rong,Chen, Tian,Wang, Yu-Liang
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p. 1039 - 1042
(2013/05/08)
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- Substituents effects on activity of kynureninase from Homo sapiens and Pseudomonas fluorescens
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A series of substituted kynurenines (3-bromo-dl, 3-chloro-dl, 3-fluoro-dl, 3-methyl-dl, 5-bromo-l, 5-chloro-l, 3,5-dibromo-l and 5-bromo-3-chloro-dl) have been synthesized and tested for their substrate activity with human and Pseudomonas fluorescens kynureninase. All of the substituted kynurenines examined have substrate activity with both human as well as P. fluorescens kynureninase. For the human enzyme, 3- and 5-substituted kynurenines have k cat and kcat/Km values higher than l-kynurenine, but less than that of the physiological substrate, 3-hydroxykynurenine. However, 3,5-dibromo- and 5-bromo-3-chlorokynurenine have kcat and kcat/Km values close to that of 3-hydroxykynurenine with human kynureninase. The effects of the 3-halo substituents on the reactivity with human kynureninase may be due to electronic effects and/or halogen bonding. In contrast, for the bacterial enzyme, 3-methyl, 3-halo and 3,5-dihalokynurenines are much poorer substrates, while 3-fluoro, 5-bromo, and 5-chlorokynurenine have kcat and kcat/K m values comparable to that of its physiological substrate, l-kynurenine. Thus, 5-bromo and 5-chloro-l-kynurenine are good substrates for both human as well as bacterial enzyme, indicating that both enzymes have space for substituents in the active site near C-5. The increased activity of the 5-halokynurenines may be due to van der Waals contacts or hydrophobic effects. These results may be useful in the design of potent and/or selective inhibitors of human and bacterial kynureninase.
- Maitrani, Chandan,Phillips, Robert S.
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p. 4670 - 4677
(2013/07/26)
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- Synthesis of {2,3-dihydro-7-halopyrrolo-[(2,1-b)]-quinazolin-9-(1h)-one and 2,3-dihydro-5,7-dihalopyrrolo-[(2,1-b)]-quinazolin-9-(1h)-one}: New analogs of deoxyvasicinone
-
A series of novel halogen-substituted deoxyvasicinone f2,3-dihydro-7- halopyrrolo-[(2,1-b)]-quinazolin-9-(1H)-one and 2,3-dihydro-5,7-dihalopyrrolo- [(2,1-b)]-quinazolin-9-(1H)-oneg derivatives was synthesized by condensation of halogenated anthranilic acids (2, 3, 4, 5) with 4-aminobutyric acid (6) in refluxing m-xylene over phosphorus pentoxide for 3 h to give the desired compounds (7a-7d). Taylor & Francis Group, LLC.
- Ojo, Babatunde,Chowdhury, Bejoy K.
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scheme or table
p. 1002 - 1009
(2012/02/02)
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- Catalysis and mechanistic studies of ruthenium and osmium on synthesis of anthranilic acids
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Ruthenium, osmium and ruthenium + osmium catalyzed synthetic methodology was developed for the synthesis of anthranilic acids from indoles in good to excellent yields using bromamine-B in alkaline acetonitrile-water (1:1) at 313 K. Detailed catalysis studies of ruthenium, osmium and the mixture of both were carried out for the synthetic reactions. The positive synergistic catalytic activity of Ru(III) + Os(VIII) was observed to a large extent with the activity greater than the sum of their separate catalytic activities. Detailed kinetic and mechanistic investigations for each catalyzed reactions were carried out. The kinetic pattern and mechanistic picture of each catalyzed reaction were found to be different for each catalyst and to obey the underlying rate laws: rate = k[BAB]t[Indole][Ru(III)]x[OH-] y rate = k[BAB]t[Indole][Os(VIII)][OH-] y rate = k[BAB]t[Indole]o[Ru(III) + Os(VIII)][OH-]y where, x, y Os(VIII) > Ru(III). This trend may be attributed to the different d-electronic configuration of the catalysts. The proposed mechanisms and the rigorous kinetic models derived give results that fit well with the experimental data in each catalyzed reaction. Copyright
- Karthikeyan,Jagadeesh, Rajenahally V.,Sree Sandhya,Puttaswamy,Nithya,Kumar, S. Senthil,Bhagat
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experimental part
p. 34 - 46
(2011/09/16)
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- Bromamine-B/PdCl2 is an efficient system for the synthesis of anthranilic acids from indoles and indigos
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A convenient method has been developed for the conversion of indoles and indigos into anthranilic acids in good to excellent yields using a bromamine-B/PdCl2 system. The general process utilizes our efficient method for the oxidation of indoles and indigos in alkaline (pH 12) acetonitrile/water (1:1) at 60°C. Copyright Taylor & Francis Group, LLC.
- Kumar, C. Vinod,Shivananda,Raju, C. Nagu,Jagadeesh
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experimental part
p. 3480 - 3487
(2011/02/22)
-
- Copper-catalyzed direct amination of ortho-functionalized haloarenes with sodium azide as the amino source
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A simple copper-catalyzed direct amination of ortho-functionalized haloarenes (2-halobenzoic acid, 2-halobenzamide, and N-(2-bromophenyl)acetamide derivatives) has been developed with use of NaN3 as the amino source in ethanol, and the corresponding ortho-functionalized aromatic amines were synthesized in good to excellent yields. The protocol undergoes one-pot Ullmann-type coupling of ortho-functionalized haloarenes with NaN3 to lead to ortho-functionalized azidoarenes, followed by reduction with ethanol.
- Zhao, Haibo,Fu, Hua,Qiao, Renzhong
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experimental part
p. 3311 - 3316
(2010/08/05)
-
- Synthesis of new 1,2,3-triazolo[1,5-a]quinazolinones
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(Chemical Equation Presented) Synthesis of novel 3-substituted-1,2,3- triazolo[1,5-a]quinazolinones in high yields was performed via anionic hetero-domino reaction of appropriate substituted 2-azidobenzoates prepared from isatines and acetonitriles activated by 1,3-thiazole, 1,3-benzothiazole, 1,3,4-oxadiazole, and 1,2,4-oxadiazole rings. It was shown that acetonitriles exhibited high reactivity and were convenient methylenic compounds for such reactions providing rapid structural variation.
- Pokhodylo, Nazariy T.,Matiychuk, Vasyl S.
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scheme or table
p. 415 - 420
(2010/06/16)
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- Synthesis of some nitrogen mustrads (Quinazoline series)
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Several nitrogen mustards with quinazoline moiety have been synthesised by condensation of 4-chloroquinazoline and 4,6- dichloroquinazoline with ethanol amine, diethanolamine and N-bis (2-chloroethyl) amine hydrochloride respectively.
- Sinha, Girish Kumar,Pandey, Bibhishan,Sinha, Alka
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experimental part
p. 1401 - 1406
(2011/10/13)
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- Hybrid diarylbenzopyrimidine non-nucleoside reverse transcriptase inhibitors as promising new leads for improved anti-HIV-1 chemotherapy
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Molecular hybridization of the known anti-HIV-1 template DPC083 and etravirine based on docking model overlay has been generated a novel series of diarylbenzopyrimidine analogues (DABPs) (5a-z). These new hybrids were assessed for their activity against HIV in MT-4 cell cultures. Most of these compounds showed good activity against wild-type HIV-1 and mutant viruses. In particular, compound 5r showed the most potent activity against wild-type HIV-1 with an EC50 value of 1.8 nM, and with a selectivity index up to 111,954. It also proved more active against mutant L100I, K103N, Y188L, and K103N + Y181C RT HIV-1 strains than efavirenz.
- Zeng, Zhao-Sen,He, Qiu-Qin,Liang, Yong-Hong,Feng, Xiao-Qing,Chen, Fen-Er,Clercq, Erik De,Balzarini, Jan,Pannecouque, Christophe
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experimental part
p. 5039 - 5047
(2010/09/05)
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- Immobilized silver nanoparticles on silica gel as an efficient catalyst in nitroarene reduction
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Nanoparticles have properties that can be fine-tuned by their size as well as shape. Hence, there is significant current interest in preparing nano-materials of small size dispersity and to arrange them in close-packed aggregates. This letter describes a way of synthesising silver nanoparticles and their protection to aggregate by silica gel. The combination of catalytic quantities of immobilized silver nanoparticles with reductive ability of NaBH4 efficiently reduces aromatic nitroarenes to the corresponding amines in aqueous medium. Noteworthy is that highly chemoselective reactions were achieved in the presence of other functional groups such as halogen and carboxylic acid groups. The silver particles immobilized on silica gel are stable in the presence of oxygen for several months.
- Kiasat, Ali Reza,Mirzajani, Roya,Ataeian, Fakhri,Fallah-Mehrjardi, Mehdi
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experimental part
p. 1015 - 1019
(2011/10/05)
-
- An efficient selective reduction of aromatic azides to amines employing BF3·OEt2/NaI: Synthesis of pyrrolobenzodiazepines
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A selective and facile method for the reduction of aromatic azides to amines by employing borontrifluoride diethyl etherate and sodium iodide. This methodology has been applied towards the preparation of biologically important imine-containing pyrrolobenzodiazepines and their dilactams through intramolecular reductive-cyclization process. In this protocol the reagent systems are amenable for the generation of solution-phase combinatorial synthesis. Georg Thieme Verlag Stuttgart.
- Kamal, Ahmed,Shankaraiah,Markandeya,Reddy, Ch. Sanjeeva
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experimental part
p. 1297 - 1300
(2009/04/06)
-
- Synthesis of 2-amino-5-chlorobenzonitrile
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Synthesis of 2-amino-5-chlorobenzonitrile by using cheaper and easily available raw materials is discussed.
- Mahajan,Mahalakshmi
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p. 1299 - 1300
(2007/10/03)
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- INHIBITORS OF MACROPHAGE MIGRATION INHIBITORY FACTOR AND METHODS FOR IDENTIFYING THE SAME
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Inhibitors of MIF are provided which have utility in the treatment of a variety of disorders, including the treatment of pathological conditions associated with MIF activity. The inhibitors of MIF have the following structures (Ia), (Ib) including stereoisomers, prodrugs and pharmaceutically acceptable salts thereof, wherein n, R1, R2, R3, R4, X, and Z are as defined herein. Compositions containing an inhibitor of MIF in combination with a pharmaceutically acceptable carrier are also provided, as well as methods for use of the same.
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Page 115-116
(2010/02/08)
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- Facile reduction of aromatic nitro/azido functionality on solid support employing Al/NiCl2·6H2O and Al/NH4Cl: Synthesis of pyrrolo[2,1-c][1,4]benzodiazepines
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An efficient and mild method for the reduction of aromatic nitro and azido groups on solid support using Al/NiCl2·6H2O and Al/NH4Cl is described. This solid phase reduction technique has been applied towards the synthesis
- Kamal, Ahmed,Reddy, K. Laxma,Devaiah,Reddy, G. Suresh Kumar
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p. 4741 - 4745
(2007/10/03)
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- Ring-substituted 11-oxo-11H-indeno[1,2-b]quinoline-6-carboxamides with similar patterns of cytotoxicity to the dual topo I/II inhibitor DACA
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A series of ring-substituted analogues of the topoisomerase inhibitor 11-oxo-11H-indeno[1,2-b]quinoline-6-carboxamides was prepared and evaluated. The compounds were prepared by Pfitzinger reaction of the appropriate isatin-7-carboxylic acids and 1-indanones, followed by selective thermal decarboxylation of the resulting tetracyclic diacids, subsequent oxidation of the methylene group with alkaline permanganate under carefully controlled conditions, and 1,1'-carbonyldiimidazole-induced amidation. The compounds were evaluated in a panel of cell lines in culture. The largest increases in cytotoxicity (five to tenfold) were shown by 4-substituted analogues, with the 4-Cl derivative having an IC50 of 8nM against the Lewis lung carcinoma. Copyright (C) 1999 Elsevier Science Ltd.
- Deady, Leslie W.,Desneves, Jose,Kaye, Anthony J.,Thompson, Michelle,Finlay, Graeme J.,Baguley, Bruce C.,Denny, William A.
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p. 2801 - 2809
(2007/10/03)
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- Improved synthesis of 2-amino-5-chlorophenyl-2'-pyrrylketone, a key intermediate in the synthesis of HIV Tat-antagonists
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The reaction of a 2-phenylbenzoxazinone with pyrryl Grignard reagent is very efficient compared with that of a 2-methylbenzoxazinone. The title compound was prepared from 5-chloroanthranilic acid via the 2-phenylbenzoxazinone in 92% overall yield. This method was also successfully applied to the synthesis of 2-aminobenzophenones.
- Okabe,Sun
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p. 1861 - 1866
(2007/10/02)
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- SYNTHESIS OF 2-AMINO-3,5-DICHLOROBENZOIC ACID.
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A method has been devised for synthesis of 2-amino-3, 5-dichlorobenzoic acid by chlorination of 2-aminobenzoic acid with chlorine generated in the reaction of hydrochloric acid with hydrogen peroxide in presence of amides - formamide and N, N-dimethylformamide, with dielectric constants of 111. 5 and 37. 6 respectively at 20 degree . The influence of the chlorination temperature on the yield and quality of 2-amino-3,5-dichlorobenzoic acid was studied. Chlorination at temperatures above 55 degree increases the consumption of hydrogen peroxide by a factor of 1. 5-2. 0 and the reaction is accompanied by copious frothing and evolution of chlorine. Chlorination at 20-35 degree proceeds slowly and requires increase of the chlorination time to 30-40 h. The optimal temperature range for obtaining the maximum yield and highest quality of the product is 40-55 degree .
- Borodina
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p. 1087 - 1089
(2007/10/02)
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