59-48-3Relevant articles and documents
Oxidation of indole with CPO and GOx immobilized on mesoporous molecular sieves
Jung, Dirk,Hartmann, Martin
, p. 378 - 383 (2010)
Green chemistry and environmentally benign reaction engineering play an important role for future industrial processes. It is expected that the number of chemical reactions carried out via enzymatic catalysis will increase strongly. To achieve this aim, stable (viz. leaching and deactivation is prevented) heterogeneous biocatalysts are required. In this study, cross-linked enzyme aggregates of chloroperoxidase were grown in large-pore mesocellular foams (MCF). By changing the various synthesis parameters, the specific activity and the effective activity (viz. the enzyme activity units per mmol of adsorbed enzyme) are improved. The resulting biocatalysts composed of cross-linked chloroperoxidase and cross-linked glucose oxidase were tested in the oxidation of indole. The catalytic test under continuous operation conditions in a fixed-bed reactor confirmed that the cross-linked enzymes are less prone to leaching compared to the physically adsorbed enzymes in the pores of MCF or SBA-15.
Synthesis, Docking, and Bioavailability of 2′-Oxo-3-phenylspiro[cyclopropane-1,3′-indoline]-2,2-dicarbonitriles as Antibacterial Agents In Silico
Avula, Vijay Kumar Reddy,Chintha, Venkata Ramaiah,Vallela, Swetha,Anireddy, Jaya Shree,Chamarthi, Naga Raju,Wudayagiri, Rajendra
, p. 209 - 217 (2019)
An efficient method has been developed for the synthesis of N-alkylated 2′-oxo-3-phenylspiro[cyclopropane-1,3′-indoline]-2,2-dicarbonitrile from 3-chloroindolin-2-one and 2-benzylidenemalononitrile by using triethylamine as a base at room temperature and obtained the products in moderate to good yields. In extension, the scope of the reaction has been investigated by stepwise and one-pot methods. Furthermore, in silico antibacterial activity was carried out in order to understand possible binding modes of novel derivatives with the active site of DNA gyrase A enzyme, and the results were well complemented. Additionally, absorption, distribution, metabolism, and excretion properties of compounds have shown drug likeness with good oral absorption and moderate blood–brain barrier permeability.
Kinetics and mechanism of meso-tetraphenylporphyriniron(III) chloride catalyzed oxidation of indole by peroxomonosulphate
Kungumathilagam,Karunakaran
, p. 4311 - 4314 (2013)
Mechanistic study on meso-tetraphenylporphyriniron(III) chloride (TPP) catalyzed oxidation of indole by peroxomonosulphate in aqueous acetonitrile medium have been carried out. The reaction follows a fractional order (0.57) with respect to substrate and first order with respect to oxidant. The order with respect to catalyst was found to be one. Increase in percentage of acetonitrile decreased the rate of the reaction. The added H+ did not affect the reaction rate. The reaction fails to initiate polymerization and free radical mechanism is ruled out. Activation and thermodynamic parameters have been computed. Nucleophilic attack of the ethylenic bond on the persulphate oxygen in presence of mesotetraphenylporphyriniron( III) chloride is envisaged to explain the reactivity. A suitable kinetic scheme based on the observations was proposed. Significant catalytic activity is observed for the reaction system in the presence of meso-tetraphenylporphyriniron(III) chloride.
Paramagnetic nuclear magnetic resonance relaxation and molecular mechanics studies of the chloroperoxidase-indole complex: Insights into the mechanism of chloroperoxidase-catalyzed regioselective oxidation of indole
Zhang, Rui,He, Qinghao,Chatfield, David,Wang, Xiaotang
, p. 3688 - 3701 (2013)
To unravel the mechanism of chloroperoxidase (CPO)-catalyzed regioselective oxidation of indole, we studied the structure of the CPO-indole complex using nuclear magnetic resonance (NMR) relaxation measurements and computational techniques. The dissociation constant (KD) of the CPO-indole complex was calculated to be approximately 21 mM. The distances (r) between protons of indole and the heme iron calculated via NMR relaxation measurements and molecular docking revealed that the pyrrole ring of indole is oriented toward the heme with its 2-H pointing directly at the heme iron. Both KD and r values are independent of pH in the range of 3.0-6.5. The stability and structure of the CPO-indole complex are also independent of the concentration of chloride or iodide ion. Molecular docking suggests the formation of a hydrogen bond between the NH group of indole and the carboxyl O of Glu 183 in the binding of indole to CPO. Simulated annealing of the CPO-indole complex using r values from NMR experiments as distance restraints reveals that the van der Waals interactions were much stronger than the Coulomb interactions in the binding of indole to CPO, indicating that the association of indole with CPO is primarily governed by hydrophobic rather than electrostatic interactions. This work provides the first experimental and theoretical evidence of the long-sought mechanism that leads to the "unexpected" regioselectivity of the CPO-catalyzed oxidation of indole. The structure of the CPO-indole complex will serve as a lighthouse in guiding the design of CPO mutants with tailor-made activities for biotechnological applications.
Kinetics and mechanism of oxidation of indole by HSO5 -
Meenakshisundaram, Subbiah,Sarathi
, p. 46 - 51 (2007)
Mechanistic studies on the oxidation of indole [IND] by HSO 5- in aqueous CH3CN medium (80:20 v/v) have been carried out, and the reaction is characterized by the rate law -d[HSO 5-]/dt = k[IND][HSO5-]HSO5 - and SO52- are probably the respective electrophiles in acidic and basic mediums. Nucleophilic attack of the ethylenic bond on the persulfate oxygen is envisaged to explain the reactivity. The reaction fails to initiate polymerization, and a radical mechanism is ruled out. Thermodynamic parameters very much suggest a bimolecular process. No significant catalytic activity is observed for the reaction system in the presence of Ag+, Cu2+, and heteroaromatic N-bases.
Transition-metal-catalyzed electrophilic activation of 1,1-difluoro-1- alkenes: Oxindole synthesis via intramolecular amination
Tanabe, Hiroyuki,Ichikawa, Junji
, p. 248 - 249 (2010)
In the presence of a catalytic amount of palladium(II) chloride, β,β-difluorostyrenes bearing a sulfonamido group at the ortho position were treated with trimethylsilyl trifluoro-methanesulfonate to afford oxindoles in high yield. The reactions proceeded via 5-endo-trig cyclization, hydrolysis, and desulfonylation. This sequence allowed the transformation of difluorostyrenes into free oxindoles in a one-pot operation.
Dihalide impurity in ziprasidone hydrochloride intermediate and preparation method of dihalide impurity
-
, (2021/05/01)
The invention provides a dihalide impurity in a ziprasidone hydrochloride intermediate. The dihalide impurity has a structure shown as a formula 1. On the basis that the ziprasidone hydrochloride intermediate can bring in the dechlorination impurity or the preparation process contains the dechlorination step, the dechlorination impurity with a specific structure is obtained, and the preparation steps of the corresponding impurity are provided, so a corresponding technical support is provided for preparation of ziprasidone hydrochloride. The synthesis method provided by the invention has the advantages of simple process, strong controllability and mild conditions, can be used for quality standard establishment and quality control links of ziprasidone hydrochloride process research and development, production and the like, and provides technical support for ziprasidone hydrochloride medication safety. The method can be used for quality research such as qualitative and quantitative analysis of impurities in ziprasidone hydrochloride synthesis, so that the quality of ziprasidone hydrochloride can be improved, and important guiding significance is provided for reducing the medication risk of ziprasidone hydrochloride.
A novel methodology for the efficient synthesis of 3-monohalooxindoles by acidolysis of 3-phosphate-substituted oxindoles with haloid acids
Huang, Tiao,Kong, Dulin,Li, Yue,Liu, Li,Wu, Mingshu
, p. 2321 - 2328 (2021/09/22)
A novel method for the synthesis of 3-monohalooxindoles by acidolysis of isatin-derived 3-phosphate-substituted oxindoles with haloid acids was developed. This synthetic strategy involved the preparation of 3-phosphate-substituted oxindole intermediates and SN1 reactions with haloid acids. This new procedure features mild reaction conditions, simple operation, good yield, readily available and inexpensive starting materials, and gram-scalability.
Oxidative Cleavage of Indoles Mediated by Urea Hydrogen Peroxide or H2O2 in Polar Solvents
Llopis, Natalia,Gisbert, Patricia,Baeza, Alejandro
supporting information, p. 3245 - 3249 (2021/06/08)
The oxidative cleavage of indoles (Witkop oxidation) involving the use of H2O2 or urea hydrogen peroxide in combination with a polar solvent has been described. Among these solvents, 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) stands out as the one affording the corresponding 2-ketoacetanilides generally in higher yields The protocol described has also enabled the oxidation of different pyrroles and furans derivatives. Furthermore, the procedure was implemented in a larger-scale and HFIP was distilled from the reaction mixture and reused (up to 4 cycles) without a significant detriment in the reaction outcome, which remarks its sustainability and applicability. (Figure presented.).
Design, synthesis, and in vitro and in vivo anti-angiogenesis study of a novel vascular endothelial growth factor receptor-2 (VEGFR-2) inhibitor based on 1,2,3-triazole scaffold
Wang, De-pu,Liu, Kai-li,Li, Xin-yang,Lu, Guo-qing,Xue, Wen-han,Qian, Xin-hua,Mohamed O, Kamara,Meng, Fan-hao
, (2020/12/21)
In the past five years, our team had been committed to click chemistry research, exploring the biological activity of 1,2,3-triazole by synthesizing different target inhibitors. In this study, a series of novel indole-2-one derivatives based on 1,2,3-triazole scaffolds were synthesized for the first time, and their inhibitory activity on vascular endothelial growth factor receptor-2 (VEGFR-2) was tested. Most of the compounds had shown promising activity in the VEGFR-2 kinase assay and had low toxicity to human umbilical vein endothelial cells (HUVECs). The compound 13d (IC50 = 26.38 nM) had better kinase activity inhibition ability than sunitinib (IC50 = 83.20 nM) and was less toxic to HUVECs. Moreover, it had an excellent inhibitory effect on HT-29 and MKN-45 cells. On the one hand, by tube formation assay, transwell, and Western blot analysis, compound 13d could inhibit VEGFR-2 protein phosphorylate on HUVECs, thereby inhibiting HUVECs migration and tube formation. In vivo study, the zebrafish model with VEGFR-2 labeling also verified that compound 13d had more anti-angiogenesis ability than sunitinib. On the other hand, molecular docking and molecular dynamics (MD) simulation results showed that compound 13d could stably bind to the active site of VEGFR-2. Based on the above findings, compound 13d could be considered an effective anti-angiogenesis drug and has more development value than sunitinib.