5234-26-4Relevant academic research and scientific papers
An Iron(III) Superoxide Corrole from Iron(II) and Dioxygen
Albert, Therese,Goldberg, David P.,Mo?nne-Loccoz, Pierre,Sacramento, Jireh Joy D.,Siegler, Maxime
, (2021/12/03)
A new structurally characterized ferrous corrole [FeII(ttppc)]? (1) binds one equivalent of dioxygen to form [FeIII(O2?.)(ttppc)]? (2). This complex exhibits a 16/18O2-isotope sensitive ν(O-O) stretch at 1128 cm?1 concomitantly with a single ν(Fe-O2) at 555 cm?1, indicating it is an η1-superoxo (“end-on”) iron(III) complex. Complex 2 is the first well characterized Fe-O2 corrole, and mediates the following biologically relevant oxidation reactions: dioxygenation of an indole derivative, and H-atom abstraction from an activated O?H bond.
PhIO-Mediated oxidative dethioacetalization/dethioketalization under water-free conditions
Du, Yunfei,Ouyang, Yaxin,Wang, Xi,Wang, Xiaofan,Yu, Zhenyang,Zhao, Bingyue,Zhao, Kang
, p. 48 - 65 (2021/06/16)
Treatment of thioacetals and thioketals with iodosobenzene in anhydrous DCM conveniently afforded the corresponding carbonyl compounds in high yields under water-free conditions. The mechanistic studies indicate that this dethioacetalization/dethioketalization process does not need water and the oxygen of the carbonyl products comes from the hypervalent iodine reagent.
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.).
Auto-tandem PET and EnT photocatalysis by crude chlorophyll under visible light towards the oxidative functionalization of indoles
Banu, Saira,Choudhari, Shubham,Patel, Girija,Yadav, Prem P.
supporting information, p. 3039 - 3047 (2021/05/05)
Chlorophyll is the most abundant photocatalytic pigment that enables plants to absorb solar energy and convert it to energy storage molecules. Herein, we report a tandem photocatalytic approach utilizing the natural pigment chlorophyll in crude form to achieve photoinduced electron transfer (PET) and energy transfer (EnT) towards the oxidative functionalization of indoles. Redox potentials, ESR, fluorescence quenching and UV experiments have evidenced the dual catalytic activity of chlorophyll. The highlight of the study is the auto-tandem photocatalytic role of chlorophyll to enable the green oxidation of indoles using molecular oxygen as the oxidant, water as the reaction medium, and photochemical energy from the visible region of the spectrum.
Visible-Light-Mediated Dearomatisation of Indoles and Pyrroles to Pharmaceuticals and Pesticides
Schilling, Waldemar,Zhang, Yu,Riemer, Daniel,Das, Shoubhik
supporting information, p. 390 - 395 (2019/12/15)
Dearomatisation of indole derivatives to the corresponding isatin derivatives has been achieved with the aid of visible light and oxygen. It should be noted that isatin derivatives are highly important for the synthesis of pharmaceuticals and bioactive compounds. Notably, this chemistry works excellently with N-protected and protection-free indoles. Additionally, this methodology can also be applied to dearomatise pyrrole derivatives to generate cyclic imides in a single step. Later this methodology was applied for the synthesis of four pharmaceuticals and a pesticide called dianthalexin B. Detailed mechanistic studies revealed the actual role of oxygen and photocatalyst.
Modeling Tryptophan/Indoleamine 2,3-Dioxygenase with Heme Superoxide Mimics: Is Ferryl the Key Intermediate?
Mondal, Pritam,Wijeratne, Gayan B.
, p. 1846 - 1856 (2020/01/31)
Tryptophan oxidation in biology has been recently implicated in a vast array of paramount pathogenic conditions in humans, including multiple sclerosis, rheumatoid arthritis, type-I diabetes, and cancer. This 2,3-dioxygenative cleavage of the indole ring of tryptophan with dioxygen is mediated by two heme enzymes, tryptophan 2,3-dioxygenase (TDO) and indoleamine 2,3-dioxygenase (IDO), during its conversion to N-formylkynurenine in the first and rate-limiting step of kynurenine pathway. Despite the pivotal significance of this enzymatic transformation, a vivid viewpoint of the precise mechanistic events is far from complete. A heme superoxide adduct is thought to be the active oxidant in both TDO and IDO, which, following O-O bond cleavage, presumably generates a key ferryl (FeIV=O) reaction intermediate. This study, for the first time in model chemistry, demonstrates the potential of synthetic heme superoxide adducts to mimic the bioinorganic chemistry of indole dioxygenation by TDO and IDO, challenging the widely accepted categorization of these metal adducts as weak oxidants. Herein, an electronically divergent series of ferric heme superoxo oxidants mediates the facile conversion of an array of indole substrates into their corresponding 2,3-dioxygenated products, while shedding light on an unequivocally occurring, putative ferryl intermediate. The oxygenated indole products have been isolated in a?31% yield, and characterized by LC-MS, 1H and 13C NMR, and FT-IR methodologies, as well as by 18O2(g) labeling experiments. Distinctly, the most electron-deficient superoxo adduct is observed to react the fastest, specifically with the most electron-rich indole substrate, underscoring the cruciality of electrophilicity of the heme superoxide moiety in facilitating the initial indole activation step. Comprehensive understanding of such mechanistic subtleties will benefit future attempts in the rational design of salient therapeutic agents, including next generation anticancer drug targets with amplified effectivity.
Dual Effects of Cyclopentadienyl Ligands on Rh(III)-Catalyzed Dehydrogenative Arylation of Electron-Rich Alkenes
Lin, Weidong,Li, Weiwei,Lu, Dandan,Su, Feng,Wen, Ting-Bin,Zhang, Hui-Jun
, p. 8070 - 8076 (2018/08/01)
Despite extensive research on transition metal-catalyzed Fujiwara-Moritani type C-H olefinations, the alkenes used in these transformations are still mainly limited to active acrylate esters and styrenes. Selective aryl C-H olefination with electron-rich alkenes is recognized as a challenging issue. We herein report that simple and readily accessible electron-deficient [CpRh(III)] and [CpCF3Rh(III)] (CpCF3 = C5Me4CF3) complexes are powerful catalysts for dehydrogenative arylation of electron-rich alkenes, including vinyl acetates, enamides, and vinyl ethers. Employing an electron-withdrawing Cp or CpCF3 ligand instead of the privileged Cp? (C5Me5) ligand not only can facilitate the electrophilic aryl C-H rhodation but also can lower the olefin insertion barrier. Both electron-withdrawing and electron-donating directing groups such as -CONR2 and -NHAc could be employed in these reactions, which provides convenient routes toward a series styryl acetates, N-acetylindoles, and aryl methyl ketones.
2-aryl-2,3-dihydro-4(1H)-quinolinone semicarbazone compound and application thereof
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, (2018/10/19)
The invention relates to the field of medicine technology, and a series of novel 2-aryl-2,3-dihydrogen-4(1H)-quinolinone semicarbazone derivatives (I) and pharmaceutically acceptable salts, solvates,optical isomers or polymorphs are designed and synthesized. The derivative (I) and its pharmaceutically acceptable salt, solvate, optical isomer or polymorph can be mixed as an active ingredient witha pharmaceutically acceptable carrier to prepare a pharmaceutical composition. A double dilution method is used for test of the antifungal activity of the derivative (I) and its pharmaceutically acceptable salt, solvate, optical isomer or polymorph, and the results show that the derivative has stronger killing effect on clinically common pathogenic fungi, and is expected to overcome the defects oflarge toxic and side effects, easy generation of drug resistance of azole antifungal medicines which are widely used clinically. The specific formula is shown in the description.
Thiazolidine derivatives or salts thereof as an active ingredient an inhibitor Pim
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Paragraph 0721; 0722, (2018/10/19)
PROBLEM TO BE SOLVED: To provide compounds which have excellent Pim inhibitory action and are useful as pharmaceuticals.SOLUTION: A compound is a thiazolidine derivative represented by the general formula (1) in the figure, or a salt thereof. (In the formula, X represents O or S; Rrepresents a hydrogen atom or a Calkyl group; Z, Z, Z, Z, Zand Zeach independently represent CH or N; Y represents an optionally substituted, divalent Caromatic hydrocarbon group or the like; Am represents a disubstituted amino group, or an optionally substituted, nitrogen-containing saturated heterocyclic group; and Rand Reach independently represent a hydrogen atom, a halogen atom, an alkyl group or the like.)
Palladium-catalyzed hydroformylation of terminal arylacetylenes with glyoxylic acid
Liu, Yang,Cai, Liangzhen,Xu, Sheng,Pu, Weiwen,Tao, Xiaochun
supporting information, p. 2166 - 2168 (2018/03/06)
A simple, practical and governable palladium-catalyzed hydroformylation of terminal arylacetylenes has been disclosed. The reaction proceeds under syngas-free conditions, using readily available glyoxylic acid as the formyl source, under mild conditions, giving rise to a broad range of α,β-unsaturated aldehydes.
