103-84-4Relevant articles and documents
Optimizing Water Exchange Rates and Rotational Mobility for High-Relaxivity of a Novel Gd-DO3A Derivative Complex Conjugated to Inulin as Macromolecular Contrast Agents for MRI
Granato, Luigi,Vander Elst, Luce,Henoumont, Celine,Muller, Robert N.,Laurent, Sophie
, (2018)
Thanks to the understanding of the relationships between the residence lifetime τM of the coordinated water molecules to macrocyclic Gd-complexes and the rotational mobility τR of these structures, and according to the theory for paramagnetic relaxation, it is now possible to design macromolecular contrast agents with enhanced relaxivities by optimizing these two parameters through ligand structural modification. We succeeded in accelerating the water exchange rate by inducing steric compression around the water binding site, and by removing the amide function from the DOTA-AA ligand [1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid mono(p-aminoanilide)] (L) previously designed. This new ligand 10[2(1-oxo-1-p-propylthioureidophenylpropyl]-1,4,7,10-tetraazacyclodecane-1,4,7-tetraacetic acid (L1) was then covalently conjugated to API [O-(aminopropyl)inulin] to get the complex API-(GdL1)x with intent to slow down the rotational correlation time (τR) of the macromolecular complex. The evaluation of the longitudinal relaxivity at different magnetic fields and the study of the 17O-NMR at variable temperature of the low-molecular-weight compound (GdL1) showed a slight decrease of the τM value (τM310 =?331?ns vs. τM310 =?450?ns for the GdL complex). Consequently to the increase of the size of the API-(GdL1)x complex, the rotational correlation time becomes about 360 times longer compared to the monomeric GdL1 complex (τR?=?33,700?ps), which results in an enhanced proton relaxivity.
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Venkataraman,K.,Wagle,D.R.
, p. 3037 - 3040 (1979)
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Hall
, p. 3188 (1964)
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Impregnated copper on Fe3O4: an efficient magnetically separable nanocatalyst for rapid and selective acylation of amines
Shokri, Zahra,Zeynizadeh, Behzad
, p. 2467 - 2474 (2017)
The present paper describes the synthesis of N-arylacetamides through acetylation of arylamines with Ac2O in the presence of magnetically recyclable Fe3O4/Cu NPs. All reactions were carried out efficiently in H2O within 2–10?min to give the products in 89–95% yields. Selective acetylation of amines versus alcohols was carried out successfully with this acetylating system. In addition, acetylation of amines and phenols was taken place with the same reactivity. Reusability of the nanocatalyst was examined 5 times without significant loss of its catalytic activity.
A binuclear Mn(ii) complex as an efficient catalyst for transamidation of carboxamides with amines
Singh, Divya Pratap,Allam, Bharat Kumar,Singh, Krishna Nand,Singh, Vinod Prasad
, p. 1155 - 1158 (2014)
A binuclear Mn(ii) complex has been synthesized and characterized by different structural methods. The complex contains two unique oxo-bridged metal centres and has been explored as an excellent catalyst for transamidation of carboxamides with amines under solvent-free conditions.
Harnessing the pyrroloquinoxaline scaffold for FAAH and MAGL interaction: Definition of the structural determinants for enzyme inhibition
Brindisi, Margherita,Brogi, Simone,Maramai, Samuele,Grillo, Alessandro,Borrelli, Giuseppe,Butini, Stefania,Novellino, Ettore,Allarà, Marco,Ligresti, Alessia,Campiani, Giuseppe,Di Marzo, Vincenzo,Gemma, Sandra
, p. 64651 - 64664 (2016)
This paper describes the development of piperazine and 4-aminopiperidine carboxamides/carbamates supported on a pharmacogenic pyrroloquinoxaline scaffold as inhibitors of the endocannabinoid catabolizing enzymes fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL). Structure-activity relationships and molecular modelling studies allowed the definition of the structural requirements for dual FAAH/MAGL inhibition and led to the identification of a small set of derivatives (compounds 5e, i, k, m) displaying a balanced inhibitory profile against both enzymes, with compound 5m being the frontrunner of the subset. Favorable calculated physico-chemical properties suggest further investigation for specific analogues.
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Soloway,Friess
, p. 5000 (1951)
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Kenner,Stedman
, p. 2069,2075 (1952)
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Cohen,Harrison
, p. 1060 (1897)
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The effect of flavonoid aglycones on the CYP1A2, CYP2A6, CYP2C8 and CYP2D6 enzymes activity
Boji?, Mirza,Kond?a, Martin,Rimac, Hrvoje,Benkovi?, Goran,Male?, ?eljan
, (2019)
Cytochromes P450 are major metabolic enzymes involved in the biotransformation of xenobiotics. The majority of xenobiotics are metabolized in the liver, in which the highest levels of cytochromes P450 are expressed. Flavonoids are natural compounds to which humans are exposed through everyday diet. In the previous study, selected flavonoid aglycones showed inhibition of CYP3A4 enzyme. Thus, the objective of this study was to determine if these flavonoids inhibit metabolic activity of CYP1A2, CYP2A6, CYP2C8, and CYP2D6 enzymes. For this purpose, the O-deethylation reaction of phenacetin was used for monitoring CYP1A2 enzyme activity, coumarin 7-hydroxylation for CYP2A6 enzyme activity, 6-α-hydroxylation of paclitaxel for CYP2C8 enzyme activity, and dextromethorphan O-demethylation for CYP2D6 enzyme activity. The generated metabolites were monitored by high-performance liquid chromatography coupled with diode array detection. Hesperetin, pinocembrin, chrysin, isorhamnetin, and morin inhibited CYP1A2 activity; apigenin, tangeretin, galangin, and isorhamnetin inhibited CYP2A6 activity; and chrysin, chrysin-dimethylether, and galangin inhibited CYP2C8. None of the analyzed flavonoids showed inhibition of CYP2D6. The flavonoids in this study were mainly reversible inhibitors of CYP1A2 and CYP2A6, while the inhibition of CYP2C8 was of mixed type (reversible and irreversible). The most prominent reversible inhibitor of CYP1A2 was chrysin, and this was confirmed by the docking study.
Ruthenium(III) acetylacetonate [Ru(acac)3] -An efficient recyclable catalyst for the acetylation of phenols, alcohols, and amines under neat conditions
Varala, Ravi,Nasreen, Aayesha,Adapa, Srinivas R.
, p. 148 - 152 (2007)
A catalytic amount of ruthenium(III) acetylacetonate (2 mol%) [Ru(acac)3] enables solvent-free acetylation of phenols, alcohols, and amines at ambient temperature in good to excellent yields. Furthermore, the catalyst could be recovered and reused at least three times without a significant loss in yields.
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Tanaka
, p. 213,214 (1970)
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Eco-friendly reductive acetamidation of arylnitro compounds by thioacetate anion through in situ catalytic regeneration: application in the synthesis of Acetaminophen
Bhattacharya, Apurba,Suarez, Victor,Tamez Jr., Victoriano,Wu, Jiejun
, p. 3221 - 3223 (2006)
A novel one-step reductive acetamidation of arylnitro compounds mediated by thioacetate anion in thioacetic acid via in situ catalytic regeneration was developed and applied to an efficient synthesis of Acetaminophen.
Selective N-acetylation of aromatic amines using acetonitrile as acylating agent
Saikia, Ujwal Pratim,Hussain, Farhaz L.,Suri, Mrinaly,Pahari, Pallab
, p. 1158 - 1160 (2016)
A method for N-acetylation of amines has been developed using acetonitrile as an acylating agent and in situ generated trimethylsilyl iodide as the catalyst under microwave heating condition. The reaction is selective toward aromatic amines while aliphatic amines remain intact. The process eliminates the requirement of toxic acylating reagents like acetic anhydride and acetyl chloride.
1,2-Diethoxyethane catalyzed oxidative cleavage of gem-disubstituted aromatic alkenes to ketones under minimal solvent conditions
Liu, Kai-Jian,Deng, Ji-Hui,Zeng, Tang-Yu,Chen, Xin-Jie,Huang, Ying,Cao, Zhong,Lin, Ying-Wu,He, Wei-Min
, p. 1868 - 1872 (2020)
Aerobic oxidation using pure dioxygen gas as the oxidant has attracted much attention, but its application in synthetic chemistry has been significantly hampered by the complexity of catalytic system and potential risk of high-energy dioxygen gas. By employing 1,2-diethoxyethane as a catalyst and ambient air as an oxidant, an efficient protocol for the construction of various aryl-alkyl and diaryl ketones through oxidative cleavage of gem-disubstituted aromatic alkenes under minimal solvent conditions has been achieved.
Activation of Superoxide; Efficient Desulphurization of Thioamides to the Corresponding Amides using a Peroxyphosphorus Intermediate generated from Phenylphosphonic Dichloride and Superoxide
Kim, Yong Hae,Lim, Sang Chul,Chang, Hae Sung
, p. 36 - 37 (1990)
Treatment of thioamides with a peroxyphosphorus intermediate generated from phenylphosphonic dichloride and superoxide (O2-radical-anion) at -4 deg C in acetonitrile gave the corresponding amides in excellent yields.
Convenient, cost-effective, and mild method for the N-acetylation of anilines and secondary amines
Prasad,Srinivasa,Channe Gowda
, p. 1189 - 1195 (2005)
An efficient, cost-effective, and mild method for the N-acetylation of anilines and secondary amines with ammonium acetate in acetic acid media at reflux temperature in good yield is described. Copyright Taylor & Francis, Inc.
Acyl transfer catalysis with 1,2,4-Triazole anion
Yang, Xing,Birman, Vladimir B.
, p. 1499 - 1502 (2009)
1,2,4-Triazole anion has been identified as an active acyl transfer catalyst suitable for the aminolysis and transesterification of esters.
Cyanuric chloride catalyzed Beckmann rearrangement of ketoximes in biodegradable ionic liquids
Maia, Angelamaria,Albanese, Domenico C.M.,Landini, Dario
, p. 1947 - 1950 (2012)
Imidazolium-based ionic liquids (ILs) containing ester moieties in the side chain were successfully used as an alternative to traditional ILs in the Beckmann rearrangement of ketoximes catalyzed by 2,4,6-trichloro[1,3,5]triazine. The procedure is mild and suitable for both aromatic and cycloaliphatic substrates affording the rearrangement products in good to quantitative yields. The process is eco-sustainable since these ILs are biodegradable and in addition they can be recovered and reused.
Beckmann rearrangement of O-4-pentenyl oxime through N- bromosuccinimide-mediated activating process
Kitagawa, Osamu,Fujita, Masao,Okada, Midori,Taguchi, Takeo
, p. 32 - 35 (1997)
Beckmann rearrangement of O-4-pentenyl oxime derivatives proceeds in good yield under mild conditions through the formation of a cationic tetrahydrofuranium intermediate in the halocyclization reaction with N- bromosuccinimide.
The ortho-substituted N,N-diacetylaniline as a selective acetylating reagent
Murakami, Yasuoki,Kondo, Kazuhiro,Miki, Kazuki,Akiyama, Yoko,Watanabe, Toshiko,Yokoyama, Yuusaku
, p. 3751 - 3754 (1997)
Selective acetylation of the less hindered amino group in the presence of the more hindered amino group with the use of 2-trifluoromethyl-N,N-diacetylaniline 2c is described. This acetylation with 2c yielded the corresponding less hindered monoacetamide exclusively, simply, conveniently, and in good yields.
Indium mediated reductive acylations of nitroarenes towards N,O-diacylated N-arylhydroxylamines
Kim,Jae Wook Cheong,Han,Jun,Baik,Lee
, p. 3577 - 3586 (2001)
By applying indium, Ac2O, MeOH, and catalytic amount of InCl3 in CHCl3 solution, nitroarenes were transformed into N,O-diacylated N-arylhydroxylamines in moderate to excellent yields.
Iterative C?H Functionalization Leading to Multiple Amidations of Anilides
Park, Juhyeon,Lee, Jia,Chang, Sukbok
, p. 4256 - 4260 (2017)
Polyaminobenzenes were synthesized by the ruthenium-catalyzed iterative C?H amidation of anilides using dioxazolones as an amino source. This strategy could be implemented by the sequential activation of C?H bonds of formerly generated compounds by cascade chelation assistance of newly installed amide groups. Computational studies provided a rationale.
Zinc(II)-Catalyzed Synthesis of Secondary Amides from Ketones via Beckmann Rearrangement Using Hydroxylamine-O-sulfonic Acid in Aqueous Media
Verma, Saumya,Kumar, Puneet,Khatana, Anil K.,Chandra, Dinesh,Yadav, Ajay K.,Tiwari, Bhoopendra,Jat, Jawahar L.
, p. 3272 - 3276 (2020)
A zinc(II)-catalyzed single-step protocol for the Beckmann rearrangement using hydroxylamine-O-sulfonic acid (HOSA) as the nitrogen source in water was developed. This direct method efficiently produces secondary amides under open atmosphere in a pure form after basic aqueous workup. It isenvironmentally benign and operationally simple.
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Horino,Inoue
, p. 2403 (1979)
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Noncross-linked polystyrene nanoencapsulation of ferric chloride: A novel and reusable heterogeneous macromolecular Lewis acid catalyst toward selective acetylation of alcohols, phenols, amines, and thiols
Alinejad, Sara,Donyapeyma, Ghazaleh,Rahmatpour, Ali
, (2022/01/24)
Ferric chloride has been successfully nanoencapsulated for the first time on a non-cross-linked polystyrene matrix as the shell material via the coacervation technique. The resulting polystyrene nanoencapsulated ferric chloride was used as a novel and rec
Protodesilylation of Arylsilanes by Visible-Light Photocatalysis
García Manche?o, Olga,Kuhlmann, Jan H.,Uygur, Mustafa
supporting information, p. 1689 - 1694 (2022/03/14)
The first visible-light-mediated photocatalytic, metal- and base-free protodesilylation of arylsilanes is presented. The C(sp2)-Si bond cleavage process is catalyzed by a 5 mol % loading of a commercially available acridinium salt upon blue-light irradiation. Two simple approaches have been identified employing either aerobic or hydrogen atom transfer cocatalytic conditions, which enable the efficient and selective desilylation of a broad variety of simple and complex arylsilanes under mild conditions.
Magnetically recyclable silica-coated ferrite magnetite-K10montmorillonite nanocatalyst and its applications in O, N, and S-acylation reaction under solvent-free conditions
Kumar, Pushpendra,Patil, Shripad M.,Tandon, Nitin,Tandon, Runjhun
, p. 21291 - 21300 (2021/07/01)
Novel silica-coated ferrite nanoparticles supported with montmorillonite (K10) have been prepared successfully by using a simple impregnation method. Further, these nanoparticles were characterized by using different analytical methods like FT-IR, PXRD, EDS, and FE-SEM techniques. In addition, these nanoparticles have been explored for their catalytic activity for the O, N, and S-acylation reactions under solvent-free conditions which gave moderate to excellent yields in a much shorter reaction time. Moreover, these nanoparticles could easily be separated out from the reaction medium after the reaction completion by using an external magnetic field and have been re-used for 10 cycles without any significant loss of the catalytic activity.
