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Jianming Zhao, Fen He, Fan Zhang, Xin Yang, Zhiyue Tian, Ying Xue
The role of water in the uncatalyzed aldol reaction of N-methyl-2,4-thiazolidinedione with N-methyl-isatin has been investigated using Monte Carlo statistical mechanics simulations utilizing the free-energy perturbation theory and the QM/MM model with PDDG/PM3 for the QM method under the "on water" and dimethyl sulfoxide (DMSO) environments. There are several conceivable orientations between thiazolidinedione and isatin in the process of C-C bond formation. However, the formation of C-C bond takes place between the re face of isatin and the si face of E-enol of the thiazolidinedione to form the preferred anti-type product, which results from enhancing hydrogen bonding interaction between water molecules and the oxygen atoms undergoing bond broken and bond formation during the reaction...
May 23, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
Guang-Jian Mei, Chen-Yu Bian, Guo-Hao Li, Shao-Li Xu, Wen-Qin Zheng, Feng Shi
The first catalytic asymmetric construction of the tryptanthrin skeleton has been established, taking advantage of a palladium(0)/chiral ligand-catalyzed enantioselective decarboxylative [4 + 2] cyclization of vinyl benzoxazinanones with isatins. This reaction has not only provided a direct and efficient method for constructing chiral tryptanthrin skeleta in high yields and excellent enantioselectivities (up to 97% yield, >99% ee) but also represents the first catalytic asymmetric decarboxylative cyclization of vinyl benzoxazinanones with isatins...
May 25, 2017: Organic Letters
Can Li, Han Lu, Xiao-Xue Sun, Guang-Jian Mei, Feng Shi
A chiral phosphoric acid-catalyzed asymmetric [3 + 3] cycloaddition of C3-substituted 2-indolylmethanols with isatin-derived azomethine ylides has been established, which afforded chiral spirooxindoles in considerable yields, moderate to good enantioselectivities and excellent diastereoselectivities (up to 85% yield, 96 : 4 er, all >95 : 5 dr).
May 24, 2017: Organic & Biomolecular Chemistry
Peng Qian, Ji-Hu Su, Yukang Wang, Meixiang Bi, Zhenggen Zha, Zhiyong Wang
2'-Aminoacetophenones undergo a C(sp3)-H oxidation and a following intramolecular C-N bond formation by virtue of a simply electrochemical oxidation in the presence of n-Bu4NI, providing various isatins with moderate to good yields. The reaction intermediates were detected, and a radical-based pathway was proposed.
May 24, 2017: Journal of Organic Chemistry
Jecika Maciel Velasques, Vanessa Carratu Gervini, Lisliane Kickofel, Renan Lira de Farias, Adriano Bof de Oliveira
The acetic acid-catalyzed reaction between 5-chloro-isatin and 4-methyl-thio-semicarbazide yields the title compound, C10H9ClN4OS (I) (common name: 5-chloro-isatin-4-methyl-thio-semicarbazone). The mol-ecule is nearly planar (r.m.s. deviation = 0.047 Å for all non-H atoms), with a maximum deviation of 0.089 (1) Å for the O atom. An S(6) ring motif formed by an intra-molecular N-H⋯O hydrogen bond is observed. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, forming chains propagating along the a-axis direction...
May 1, 2017: Acta Crystallographica. Section E, Crystallographic Communications
Liang-Liang Zhao, Xing-Shuo Li, Li-Li Cao, Rui Zhang, Xiao-Qian Shi, Jing Qi
A strategy for the NHC-catalyzed synthesis of dihydropyridinones and spirooxindoles has been developed via [3+3] annulation reactions of enals or isatin-derived enals with 2-aminoacrylates under oxidative conditions. In this efficient strategy, the 2-aminoacrylates served as nucleophiles. Modifying the standard base switched the carbon-carbon double bond formation from 5,6-positions to 3,4-positions to generate 5,6-dihydropyridinones and 3,4-dihydropyridinones, respectively. Meanwhile, a diverse set of spirooxindole derivatives were also synthesized in good to excellent yields...
May 17, 2017: Chemical Communications: Chem Comm
Shuai Gao, Jie Zang, Qianwen Gao, Xuewu Liang, Qinge Ding, Xiaoyang Li, Wenfang Xu, C James Chou, Yingjie Zhang
As a hot topic of epigenetic studies, histone deacetylases (HDACs) are related to lots of diseases, especially cancer. Further researches indicated that different HDAC isoforms played various roles in a wide range of tumor types. Herein a novel series of HDAC inhibitors with isatin-based caps and o-phenylenediamine-based zinc binding groups have been designed and synthesized through scaffold hopping strategy. Among these compounds, the most potent compound 9n exhibited similar if not better HDAC inhibition and antiproliferative activities against multiple tumor cell lines compared with the positive control entinostat (MS-275)...
March 19, 2017: Bioorganic & Medicinal Chemistry
Lei Zhang, Hong Lu, Guo-Qiang Xu, Zhu-Yin Wang, Peng-Fei Xu
A PPh3 mediated reductive annulation reaction between isatins and 4,4-dicyano-2-methylenebut-3-enoates was developed. The reaction provided an alternative method for constructing five- and three-membered all-carbon spirooxindole compounds. Lithium chloride as a Lewis acid played a key role in the synthesis of spirocyclopentenyl oxindole compounds.
May 19, 2017: Journal of Organic Chemistry
Anshu Dandia, Shahnawaz Khan, Pragya Soni, Aayushi Indora, Dinesh Kumar Mahawar, Prateek Pandya, Chetan Singh Chauhan
A simple, environmentally benign and highly proficient microwave assisted one-pot approach for the synthesis of antimicrobial spiropyrrolidine/thiapyrrolizidine oxindole derivatives is reported assembling two pharmacophoric moieties (1,3-indanedione and pyrrolidine/thiapyrrolizidine) in a single molecular framework via three-component 1,3-dipolar cycloaddition reaction of substituted isatin, sarcosine/1,3-thiazoles-4-carboxylic acid and Knoevenagel adduct (2-Cyano-3-phenyl-acrylic acid ethyl ester or 2-Benzylidene-malononitrile) in 2,2,2-trifluoroethanol as a reusable green solvent...
April 27, 2017: Bioorganic & Medicinal Chemistry Letters
Tarek B Ahmad, David Rudd, Joshua Smith, Michael Kotiw, Peter Mouatt, Lisa M Seymour, Lei Liu, Kirsten Benkendorff
Marine molluscs are rich in biologically active natural products that provide new potential sources of anti-inflammatory agents. Here we used bioassay guided fractionation of extracts from the muricid Dicathais orbita to identify brominated indoles with anti-inflammatory activity, based on the inhibition of nitric oxide (NO) and tumour necrosis factor α (TNFα) in lipopolysaccharide (LPS) stimulated RAW264.7 macrophages and prostaglandin E2 (PGE2) in calcium ionophore-stimulated 3T3 ccl-92 fibroblasts. Muricid brominated indoles were then compared to a range of synthetic indoles to determine structure-activity relationships...
May 6, 2017: Marine Drugs
Yan-Shuo Zhu, Bei-Bei Yuan, Jiao-Mei Guo, Shao-Jing Jin, Hua-Hui Dong, Qi-Lin Wang, Zhan-Wei Bu
An efficient Cu(OTf)2-catalyzed Friedel-Crafts alkylation/cyclizaiton sequence of 3-substituted indoles with isatin-derived oxodienes was developed, and a series of structurally complex and diverse pyrrolo[1,2-a]indole spirooxindoles were first obtained in up to 99% yields. This protocol proved to be quite general and was also robust for the synthesis of 9H-pyrrolo[1,2-a]indoles.
May 10, 2017: Journal of Organic Chemistry
Akira Hara, Satoshi Endo, Toshiyuki Matsunaga, Ossama El-Kabbani, Takeshi Miura, Toru Nishinaka, Tomoyuki Terada
Human carbonyl reductase 1 (CBR1), a member of the short-chain dehydrogenase/reductase (SDR) superfamily, reduces a variety of carbonyl compounds including endogenous isatin, prostaglandin E2 and 4-oxo-2-nonenal. It is also a major non-cytochrome P450 enzyme in the phase I metabolism of carbonyl-containing drugs, and is highly expressed in the intestine. In this study, we found that long-chain fatty acids and their CoA ester derivatives inhibit CBR1. Among saturated fatty acids, myristic, palmitic and stearic acids were inhibitory, and stearic acid was the most potent (IC50 9µM)...
April 24, 2017: Biochemical Pharmacology
Cheng Peng, Jiaojiao Zhai, Mingqiang Xue, Fan Xu
Lanthanide amide-catalyzed one-pot reaction of isatins, dialkyl phosphite, and activated alkenes was developed and a series of spiro[cyclopropan-1,3'-oxindoles] were obtained in moderate to excellent yields. The reaction is stereoselective and the two substituents at the 2 and 3-positions of the cyclopropane in the major product are in the trans configuration. A four-step mechanism involving the Pudovik reaction, Brook rearrangement, Michael addition, and intramolecular nucleophilic substitution is proposed, and an umpolung strategy was used in the process...
May 10, 2017: Organic & Biomolecular Chemistry
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...
May 5, 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...
July 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
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