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
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, (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.
Fenton chemistry enables the catalytic oxidative rearrangement of indoles using hydrogen peroxide
Zhao, Guodong,Liang, Lixin,Wang, Eryu,Lou, Shaoyan,Qi, Rui,Tong, Rongbiao
supporting information, p. 2300 - 2307 (2021/04/12)
Oxidative rearrangement of indoles is an important transformation to yield 2-oxindoles and spirooxindoles, which are present in many pharmaceutical agents and bioactive natural products. Previous oxidation methods show either broad applicability or greenness but rarely achieve both. Reported is the discovery of Fenton chemistry-enabled green catalytic oxidative rearrangement of indoles, which has wide substrate scope (42 examples) and greenness (water as the only stoichiometric byproduct) at the same time. Detailed mechanistic studies revealed that the Fenton chemistry generated hydroxyl radicals that further oxidize bromide to reactive brominating species (RBS: bromine or hypobromous acid). Thisin situgenerated RBS is the real catalyst for the oxidative rearrangement. Importantly, the RBS is generated under neutral conditions, which addresses a long-lasting problem of many haloperoxidase mimics that require a strong acid for the oxidation of bromide with hydrogen peroxide. It is expected that this new catalytic Fenton-halide system will find wide applications in organic synthesis.
Green method for preparing oxindole derivative
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Paragraph 0027-0029, (2021/06/26)
The invention relates to the technical field of green organic synthesis, and provides a green method for preparing oxindole derivatives, which comprises the following steps: taking indole compounds with different functional groups as raw materials, under the conditions of room temperature, opening and neutral, adopting MBrx (M is Fe,Fe,Ce and the like) as a catalyst with X equal to 2 or 3, and adopting hydrogen peroxide as a sole oxidant to generate active bromine (RBS) in situ, and catalytically synthesizing the oxindole derivative. According to the method disclosed by the invention, MBrx (such as FeBr2, CeBr3 and the like) is used as the catalyst, so that an expensive or complex catalyst is avoided, and the method is green, environment-friendly, safe, simple, efficient, mild in reaction condition and wide in substrate application range, has a relatively good application prospect and is expected to be widely applied to organic synthesis, fine chemical engineering and pharmaceutical industry.
Inversion kinetics of someE/Z3-(benzylidene)-2-oxo-indoline derivatives and theirin silicoCDK2 docking studies
Mansour, Hany S.,Abd El-Wahab, Hend A. A.,Ali, Ahmed M.,Aboul-Fadl, Tarek
, p. 7839 - 7850 (2021/03/03)
The structure-based design of some CDK2 inhibitors with a 3-(benzylidene)indolin-2-one scaffold as potential anticancer agents was realized. Target compounds were obtained asE/Zmixtures and were resolved to correspondingE- andZ-diastereomers.In silicostudies using MOE 2019.01 software revealed better docking on the targeted enzyme for theZ-diastereomer compared to theE-one. A time-dependent kinetic isomerization study was carried out for the inversion ofE/Zdiastereomers in DMSO-d6at room temperature, and were found to obey the first order kinetic reactions. Furthermore, a determination of the kinetic inter-conversion rate order by graphical analysis method and calculation of the rate constant and half-life of this kinetic process were carried out. For the prediction of the stability of the diastereomer(s), a good multiple regression equation was generated between the reaction rates of isomerization and some QM parameters with significantpvalue.
