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Zhenzhen Xie, Guangcheng Wang, Jing Wang, Ming Chen, Yaping Peng, Luyao Li, Bing Deng, Shan Chen, Wenbiao Li
A series of novel isatin-thiazole derivatives were synthesized and screened for their in vitro α-glucosidase inhibitory activity. These compounds displayed a varying degree of α-glucosidase inhibitory activity with IC50 ranging from 5.36 ± 0.13 to 35.76 ± 0.31 μm as compared to the standard drug acarbose (IC50 = 817.38 ± 6.27 μm). Among the series, compound 6p bearing a hydroxyl group at the 4-position of the right phenyl and 2-fluorobenzyl substituent at the N1-positions of the 5-methylisatin displayed the highest inhibitory activity with an IC50 value of 5...
April 20, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Bing Lin, Gen Zhou, Yi Gong, Qi-Di Wei, Min-Yi Tian, Xiong-Li Liu, Ting-Ting Feng, Ying Zhou, Wei-Cheng Yuan
Described herein is the development of a facile and efficient methodology for the synthesis of novel turmerone motif-fused 3,3'-pyrrolidinyl-dispirooxindoles 3-5 via a multicomponent 1,3-dipolar cycloaddition of dienones 2 with azomethine ylides (thermally generated in situfrom isatins and proline or thioproline or sarcosine). Products bearing four or three consecutive stereocenters consist of two oxindole moieties and a pyrrolidinyl core, including vicinal spiroquaternary stereocenters fused in one ring structure were smoothly obtained in high yields (up to 93% yield) with good diastereoselectivity (up to >20:1)...
April 17, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
P V Ershov, E O Yablokov, Yu V Mezentsev, L A Kalushskiy, A V Florinskaya, A V Veselovsky, O V Gnedenko, A A Gilep, S A Usanov, A E Medvedev, A S Ivanov
Cytochromes P450 (CYP) are involved in numerous biochemical processes including metabolism of xenobiotics, biosynthesis of cholesterol, steroid hormones etc. Since some CYP catalyze indol oxidation to isatin, we have hypothesized that isatin can regulate protein-protein interactions (PPI) between components of the CYP system thus representing a (negative?) feedback mechanism. The aim of this study was to investigate a possible effect of isatin on interaction of human CYP with cytochrome b5 (CYB5A). Using the optical biosensor test system employing surface plasmon resonance (SPR) we have investigated interaction of immobilized CYB5A with various CYP in the absence and in the presence of isatin...
March 2017: Biomedit︠s︡inskai︠a︡ Khimii︠a︡
Timothy R Hodges, Noah M Benjamin, Stephen F Martin
A unique approach to gliocladin C and related alkaloids was developed that features an unprecedented nucleophilic addition of a diketopiperazine to an isatin derivative followed by a Friedel-Crafts alkylation of the resultant tertiary alcohol with indole to set the key quaternary center. Chemoselective oxindole reduction and cyclization delivered a pivotal hexahydropyrrolo[2,3-b]indole diketopiperazine intermediate that was readily converted into (±)-gliocladin C, (±)-T988C, and (±)-gliocladine C, culminating in the shortest approach to these alkaloids reported to date...
April 17, 2017: Organic Letters
Sai Prathima Parvathaneni, Bikshapathi Raktani, Y Poornachandra, Hima Bindu Vittam, G Jagadeeshkumar, Jagadeesh Nanubolu, C Ganesh, Jayathirtha Rao Vaidya
An expeditious approach for direct alkynylation of isatins (ketones) has been developed using tetrabutylammonium fluoride (TBAF) as a catalyst in THF solvent at room temperature under metal-free conditions. Furthermore this method is an economically viable process that also compliments green aspects like being a ligand/metal free process under ambient conditions. This reaction tolerated a wide range of substrates with good to excellent yields (80-94%). All the 3-hydroxy-3-ethynylindolin-2-one derivatives were subjected for in vitro cytotoxic activity on five different cancer cell lines...
April 12, 2017: Anti-cancer Agents in Medicinal Chemistry
Wenyan Sun, Li Zhang, Lin Hou, Chuanxia Ju, Shengmin Zhao, Yaoyue Wei
Isatin was reported to possess anticancer activities through its effect on tumor proliferation, apoptosis, and metastasis in vitro and in vivo. This study aimed to elucidate the underlying mechanism behind isatin's ability to inhibit neuroblastoma cell metastasis. Our results demonstrated that isatin could inhibit neuroblastoma cell proliferation, invasion, and migration in a dose-dependent manner. Moreover, isatin inhibited the expression level of monoamine oxidase A as well as that of its downstream protein hypoxia-inducible factor 1α...
April 4, 2017: Anti-cancer Drugs
Zahid Khan, Zahida Tasneem Maqsood, Asad Tanoli
Schiff bases are versatile organic compounds and are widely studied for their broad range of biological applications. Extensive experimental data is available on these compounds but theoretical aspects are not comprehensively studied so far. This paper reports quantum mechanical calculation of a Schiff base to theoretically explore the electronic structure. Semi empirical (Austin Model 1, and Parametric Method 3) methods were employed to predict the optimized geometry and calculate various electronic properties e...
November 2016: Pakistan Journal of Pharmaceutical Sciences
V U Bhaskara Rao, Krishna Kumar, Tamal Das, Kumar Vanka, Ravi P Singh
An efficient, metal-free approach to 3-substituted 3-hydroxyoxindole by DBU-mediated highly diastereoselective addition of aryl acetonitrile to N-protected isatin under mild conditions has been developed. The reaction proceeds smoothly to produce respective cyanomethylated adducts in good yield and excellent diastereoselectivity. Further transformation of the cyanide group allowed the synthesis of an advance intermediate of corresponding (±) CPC analogue. The mechanistic insight toward the aldol-type cyanomethylation of N-tritylisatin with benzyl cyanide was obtained by DFT calculations...
April 6, 2017: Journal of Organic Chemistry
Marc Montesinos-Magraner, Carlos Vila, Gonzalo Blay, Isabel Fernández, M Carmen Muñoz, José R Pedro
A Cinchona-derived squaramide catalyzes the reaction between hydroxyindoles and isatins leading to enantioenriched indoles substituted in the carbocyclic ring. The reaction proceeds efficiently with differently substituted isatins, yielding the desired products with excellent regioselectivity, good yields, and high enantiocontrol. Moreover, every position of the carbocyclic ring of the indole can be functionalized by using the appropriate starting hydroxyindole. The OH group was removed smoothly upon hydrogenolysis of the corresponding triflate...
April 7, 2017: Organic Letters
Priscila Maria Dellamatrice, Maria Estela Silva-Stenico, Luiz Alberto Beraldo de Moraes, Marli Fátima Fiore, Regina Teresa Rosim Monteiro
Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black), and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations...
January 2017: Brazilian Journal of Microbiology: [publication of the Brazilian Society for Microbiology]
Ying-Chun Chen, Gu Zhan, Ming-Lin Shi, Wei-Jia Lin, Yang Ouyang, Wei Du
Nitrones commonly act as 1,3-dipoles and electrophiles to furnish valuable isoxazolidine and N-hydroxyl products, respectively. They also can be converted to nitrone ylide species, and undergo [3+2] formal cycloadditions to access N-hydroxyl pyrrolidines. Here we first present asymmetric direct aza-vinylogous-type additions of nitrones from isatins to nitroalkenes catalyzed by a bifunctional thiourea-tertiary amine, producing highly functionalized nitrones with extended carbon skeletons in excellent stereoselectivity...
March 23, 2017: Chemistry: a European Journal
A E Medvedev, O A Buneeva, A T Kopylov, O V Tikhonova, M V Medvedeva, L N Nerobkova, I G Kapitsa, V G Zgoda
Mitochondria play an important role in molecular mechanisms of neuroplasticity, adaptive changes of the brain that occur in the structure and function of its cells in response to altered physiological conditions or development of pathological disorders. Mitochondria are a crucial target for actions of neurotoxins, causing symptoms of Parkinson's disease in various experimental animal models, and also neuroprotectors. Good evidence exists in the literature that mitochondrial dysfunction induced by the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) influences functioning of the ubiquitin-proteasomal system (UPS) responsible for selective proteolytic degradation of proteins from various intracellular compartments (including mitochondria), and neuroprotective effects of certain antiparkinsonian agents (monoamine oxidase inhibitors) may be associated with their effects on UPS...
March 2017: Biochemistry. Biokhimii︠a︡
Christian Paul Ortmeyer, Günter Haufe, Katrin Schwegmann, Sven Hermann, Michael Schäfers, Frederik Börgel, Bernhard Wünsch, Stefan Wagner, Verena Hugenberg
BODIPYs (boron dipyrromethenes) are fluorescent dyes which show high stability and quantum yields. They feature the possibility of selective (18)F-fluorination at the boron-core. Attached to a bioactive molecule and labeled with [(18)F]fluorine, the resulting compounds are promising tracers for multimodal imaging in vivo and can be used for PET and fluorescence imaging. A BODIPY containing a phenyl and a hydroxy substituent on boron was synthesized and characterized. Fluorinated and hydroxy substituted dyes were coupled to an isatin-based caspase inhibitor via cycloaddition and the resulting compounds were evaluated in vitro in caspase inhibition assays...
February 16, 2017: Bioorganic & Medicinal Chemistry
Chao-Ming Wang, Peng-Ju Xia, Jun-An Xiao, Jun Li, Hao-Yue Xiang, Xiao-Qing Chen, Hua Yang
Reductive dimerization of isatin and its derivatives can be regarded as a step-economical pathway to construct 3,3'-disubstituted bisoxindoles, which was unfortunately accompanied by severe direct reduction as well as low efficiency. A visible-light driven, photoredox-catalytic protocol was developed to readily furnish 3,3'-dihydroxy- (dl-, > 20:1 dr) and 3,3'-diamino-bisoxindoles (meso-, 3.5:1 to 5:1 dr) in moderate to good yields, successfully circumventing the common problem. Two vicinal quaternary carbon centers were effectively assembled under the irradiation of visible light...
March 28, 2017: Journal of Organic Chemistry
Jianfeng Xu, Shiru Yuan, Jingyi Peng, Maozhong Miao, Zhengkai Chen, Hongjun Ren
An asymmetric [2+2] annulation reaction through direct α-carbon functionalization of simple aldehydes via oxidative N-heterocyclic carbene catalysis is disclosed. These in situ generated triazolium enolate intermediates undergo a highly stereoselective Mannich reaction with isatin-derived ketimines followed by intramolecular lactamization to afford enantioenriched spirooxindole β-lactams bearing two vicinal stereogenic centers.
March 9, 2017: Chemical Communications: Chem Comm
Negar Lashgari, Alireza Badiei, Ghodsi Mohammadi Ziarani, Farnoush Faridbod
A highly ordered mesoporous silica material functionalized with isatin (SBA-Pr-IS) was designed and synthesized. Characterization techniques including XRD, TGA, BET, SEM, and FT-IR were employed to characterize the pore structure, textural properties, microscopic morphology, and molecular composition of grafted organic moieties of SBA-Pr-IS. The successful attachment of the organic moiety (0.34 mmol g(-1)) without the SBA-15 structure collapsing after the modification steps was confirmed. Fluorescence characterization of SBA-Pr-IS was examined upon addition of a wide variety of cations in aqueous medium and it showed high sensitivity toward Hg(2+) ions...
March 7, 2017: Analytical and Bioanalytical Chemistry
Shailendra K Singh, Nisha Chandna, Nidhi Jain
An efficient and facile method to synthesize N-Mannich bases has been developed using an inexpensive copper(I) bromide/air catalyst system at ambient temperature. A cross-dehydrogenative coupling of N,N-dimethylarylamines occurs efficiently with aromatic heterocyclic amides (oxindoles, isatins), cyclic amides (lactams), simple amides (benzamide), as well as imides (succinimide, phthalimide) to furnish the corresponding amidated/imidated derivatives in good to excellent yields. Preliminary mechanistic and isotope-labeling studies suggest the reaction follows a radical pathway and involves an iminium ion intermediate...
March 1, 2017: Organic Letters
Huwaida M E Hassaneen, Elshimaa M Eid, Hamid A Eid, Thoraya A Farghaly, Yahia Nasser Mabkhot
This article presents the synthesis of new derivatives of spirooxindole-spiropiperidinone- pyrrolidines 6a-j and spirooxindole-spiropiperidinone-pyrrolizines 8a-j, through a 1,3-dipolar cycloaddition reaction of azomethineylides generated from isatin, sarcosine, and l-proline, through a decarboxylative route with dipolarophile 4a-j. All of the newly synthesized compounds were evaluated for their antimicrobial activities and their minimum inhibitory concentration (MIC) against most of the test organisms. The tested compounds displayed excellent activity against all of the tested microorganisms...
February 26, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Xiangbin Bai, Guangkuo Zeng, Tianju Shao, Zhiyong Jiang
Reported herein is the first example of 2-allylazaarenes in asymmetric catalysis. Highly γ-selective allylation was demonstrated for activated ketones, including isatins and trifluoromethyl ketones. In the presence of either an amino-acid-based tertiary amine or quaternary ammonium salt catalyst, two series of tertiary hydroxy-containing moieties were installed at the remote δ-position of azaarenes in good chemical yields, excellent enantioselectivities, and E/Z ratios. The success of current γ-selective reactions should provide inspiration for expansion to other allylazaarene derivatives and would open up new paradigms for the synthesis of chiral γ- and/or δ-functionalized azaarenes...
February 27, 2017: Angewandte Chemie
Wengang Guo, Yan Liu, Can Li
The first enantioselective catalytic 1,2-hydroperoxidation has been achieved in the presence of PEG-600 using an acid-base bifunctional chiral squaramide as the organocatalyst, affording a range of enantioenriched α-N-substituted hydroperoxides bearing an oxindole moiety with excellent stereoselectivities (up to 99% ee).
February 23, 2017: Organic Letters
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