770-37-6Relevant academic research and scientific papers
Metal array fabrication through self-assembly of Pt-complex-bound amino acids
Isozaki, Katsuhiro,Ogata, Kazuki,Haga, Yusuke,Sasano, Daisuke,Ogawa, Tetsuya,Kurata, Hiroki,Nakamura, Masaharu,Naota, Takeshi,Takaya, Hikaru
, p. 3936 - 3938 (2012)
A new type of Pt-complex-bound amino acid was synthesized by condensation of a cyclometalated Pt complex with the side-chain residue of N- and C-alkylated glutamic acid. Self-assembly of the Pt-bound lipophilic amino acid afforded a supramolecular gel in organic solvents, which comprised fibrous lamellar aggregates that supported a highly oriented Pt array.
Radiosynthesis and evaluation of 18F-labeled dopamine D4-receptor ligands
Willmann, Michael,Ermert, Johannes,Prante, Olaf,Hübner, Harald,Gmeiner, Peter,Neumaier, Bernd
, p. 43 - 52 (2020/08/03)
Introduction: The dopamine D4 receptor (D4R) has attracted considerable attention as potential target for the treatment of a broad range of central nervous system disorders. Although many efforts have been made to improve the performance of putative radioligand candidates, there is still a lack of D4R selective tracers suitable for in vivo PET imaging. Thus, the objective of this work was to develop a D4-selective PET ligand for clinical applications. Methods: Four compounds based on previous and new lead structures were prepared and characterized with regard to their D4R subtype selectivity and predicted lipophilicity. From these, 3-((4-(2-fluorophenyl)piperazin-1-yl)methyl)-1H-pyrrolo[2,3-b]pyridine I and (S)-4-(3-fluoro-4-methoxybenzyl)-2-(phenoxymethyl)morpholine II were selected for labeling with fluorine-18 and subsequent evaluation by in vitro autoradiography to assess their suitability as D4 radioligand candidates for in vivo imaging. Results: The radiosynthesis of [18F]I and [18F]II was successfully achieved by copper-mediated radiofluorination with radiochemical yields of 7% and 66%, respectively. The radioligand [18F]II showed specific binding in areas where D4 expression is expected, whereas [18F]I did not show any uptake in distinct brain regions and exhibited an unacceptable degree of non-specific binding. Conclusions: The compounds studied exhibited high D4R subtype selectivity and logP values compatible with high brain uptake, but only ligand [18F]II showed low non-specific binding and is therefore a good candidate for further evaluation. Advances in knowledge: The discovery of new lead structures for high-affinity D4 ligands opens up new possibilities for the development of suitable PET-radioligands. Implications for patient: PET-imaging of dopamine D4-receptors could facilitate understanding, diagnosis and treatment of neuropsychiatric and neurodegenerative diseases.
Nitrogen-modified graphene as a metal-free carbocatalyst for the solvent-free oxidative homo- and heterocoupling of amines
Ganbari, Alireza,Tavakol, Hossein
, (2021/11/04)
In this study, graphene oxide (GO) has been prepared using Hammers’ method and the produced GO was converted to nitrogen-modified GO (NGO) using hydrothermal reaction with ammonia and hydrazine. The morphology of the product was confirmed with FESEM images and XRD, TEM, Raman, TGA, EDS, BET and FTIR analyses were employed to study the structure and properties of the product. The produced NGO has been employed as a catalyst for oxidative coupling of amines to imines. The reaction was carried out at 110?°C, using 4 wt% of catalyst (versus the used amine), oxygen gas as oxidative agent, solvent-free condition in 4?h with 80% yield. To determine the versatility of the reaction, different derivatives of amines such as benzylamine, phenyl hydrazine, aniline, ethylenediamine, ethanol amine and homoveratrylamine have been examined in this reaction and successfully converted to the related imines via heterocoupling reactions. Finally, the recyclability of the reaction was investigated and the results showed only 10% decreasing in the yield after 6 runs.
Synthesis of Eight-Membered Nitrogen Heterocycles via a Heterogeneous PtI2-Catalyzed Cascade Cycloaddition Reaction of δ-Aminoalkynes with Electron-Deficient Alkynes
Li, Xinhong,Wang, Songmeng,Wang, Hongkai,Wang, Weilin,Liu, Lingyan,Chang, Weixing,Li, Jing
supporting information, p. 1525 - 1531 (2020/03/23)
A novel heterogeneous PtI2-catalyzed cascade reaction of δ-aminoalkynes was developed for the synthesis of various eight-membered nitrogen heterocycles in excellent yields. The reaction proceeds via a hydration of δ-aminoalkynes and subsequent intramolecular cyclization and intermolecular addition as well as ring-expansion cascade reaction with another electron-deficient alkynes. This method has the advantages of simple operation and mild reaction conditions. And the simple PtI2 with no any supports could be readily recycled through simple centrifugation without substantial loss of activity in 1,2-dichloroethane (DCE). The recyclability of PtI2 may be ascribed to its insolubility in DCE. The reaction constitutes a formal [6+2]-cycloaddition. (Figure presented.).
STEREOSELECTIVE PROCESS FOR PREPARING SUBSTITUTED POLYCYCLIC PYRIDONE DERIVATIVES
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Paragraph 0508-0509, (2020/08/20)
The present invention provides industrially suitable processes for preparing intermediates in the production of substituted polycyclic pyridone derivatives having a cap-dependent endonuclease inhibitory activity. In the process as shown below, wherein each symbol is as defined in the specification, an optically active substituted tricyclic pyridone derivative of the formula (VII) is obtained in high yield and high enantioselectivity by subjecting a compound of the formula (III) or (VI) to intramolecular cyclization with controlling stereochemistry to obtain a compound of the formula (IV) having a removable functional group on an asymmetric carbon, and then removing the functional group thereof.
A pharmaceutical model intermediate and its preparation method
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Paragraph 0038; 0047-0050, (2019/01/22)
The invention relates to a novel intermediate and its preparation method. The intermediate can be used for preparing amlodipine or pharmaceutically acceptable salts thereof; and amlodipine or salts thereof can be prepared through preparing the intermediate. The method is simple and safe to operate, avoids the use of flammable and explosive articles, and is in favor of the industrial mass production.
Fabrication of Ultrathin 2D Cu-BDC Nanosheets and the Derived Integrated MOF Nanocomposites
Zhan, Guowu,Fan, Longlong,Zhao, Feigang,Huang, Zhongliang,Chen, Bin,Yang, Xin,Zhou, Shu-feng
, (2019/01/14)
Freestanding 2D nanosheets with many unprecedented properties have been used in a myriad of applications. In this work, 2D copper-bearing metal-organic frameworks (MOFs; viz., Cu-BDC) nanosheets are successfully fabricated via a facile and benign methodology through using Cu2O nanocubes (≈60 nm) as a confined metal ion source and 1,4-benzenedicarboxylic acid (H2BDC) as an organic linker. The Cu2O nanocubes gradually release Cu+ ions which are further oxidized by the dissolved oxygen and serve as nutrients for construction of 2D frameworks. In contrast, the conventional solvothermal synthesis with copper salt exclusively yields bulk Cu-BDC with edge dimensions of 2–10 μm. Interestingly, the as-prepared Cu-BDC nanosheets show ultrathin thickness, oriented growth, and excellent crystallinity, which can be exploited as a platform for the design of a series of 2D-integrated nanocatalysts by loading various metal nanocrystals such as Au, Ag, Pt, and Ru, with 3-mercaptopropionic acid as molecular link. In addition, it is found that Cu-BDC/M composites with highly accessible active sites on the surface exhibit high catalytic activity in several condensation reactions between benzaldehyde and primary amines. The findings offer an alternative strategy for rational design and synthesis of 2D MOF nanosheets and the derived 2D nanocomposites for catalytic applications.
Synthesis of Imines via Reactions of Benzyl Alcohol with Amines Using Half-Sandwich (η6-p-cymene) Ruthenium(II) Complexes Stabilised by 2-aminofluorene Derivatives
Vinoth, Govindasamy,Indira, Sekar,Bharathi, Madheswaran,Durgadevi, Anandhan,Abinaya, Ravikumar,Alves, Luis G.,Martins, Ana Margarida,Bharathi, Kuppannan Shanmuga
, (2019/09/03)
A new class of half-sandwich (η6-p-cymene) ruthenium(II) complexes supported by 2-aminofluorene derivatives [Ru(η6-p-cymene)(Cl)(L)] (L?=?2-(((9H-fluoren-2-yl)imino)methyl)phenol (L1), 2-(((9H-fluoren-2-yl)imino)methyl)-3-methoxyphenol (L2), 1-(((9H-fluoren-2-yl)imino)methyl)naphthalene-2-ol (L3) and N-((1H-pyrrol-2-yl)methylene)-9H-fluorene-2-amine (L4)) were synthesized. All compounds were fully characterized by analytical and spectroscopic techniques (IR, UV–Vis, NMR) and also by mass spectrometry. The solid state molecular structures of the complexes [Ru(η6-p-cymene)(Cl)(L2)], [Ru(η6-p-cymene)(Cl)(L3)] and [Ru(η6-p-cymene)(Cl)(L4)] revealed that the 2-aminofluorene and p-cymene moieties coordinate to ruthenium(II) in a three-legged piano-stool geometry. The synthesized complexes were used as catalysts for the dehydrogenative coupling of benzyl alcohol with a range of amines (aliphatic, aromatic and heterocyclic). The reactions were carried out under thermal heating, ultrasound and microwave assistance, using solvent or solvent free conditions, and the catalytic performance was optimized regarding the solvent, the type of base, the catalyst loading and the temperature. Moderately high to very high isolated yields were obtained using [Ru(η6-p-cymene)(Cl)(L4)] at 1?mol%. In general, microwave irradiation produced better yields than the other two techniques irrespective of the nature of the substituents.
Manganese catalyzed reductive amination of aldehydes using hydrogen as a reductant
Wei, Duo,Bruneau-Voisine, Antoine,Valyaev, Dmitry A.,Lugan, No?l,Sortais, Jean-Baptiste
supporting information, p. 4302 - 4305 (2018/05/03)
A one-pot two-step procedure was developed for the alkylation of amines via reductive amination of aldehydes using molecular dihydrogen as a reductant in the presence of a manganese pyridinyl-phosphine complex as a pre-catalyst. After the initial condensation step, the reduction of imines formed in situ is performed under mild conditions (50-100 °C) with 2 mol% of catalyst and 5 mol% of tBuOK under 50 bar of hydrogen. Excellent yields (>90%) were obtained for a large combination of aldehydes and amines (40 examples), including aliphatic aldehydes and amino-alcohols.
Amberlyst-15 catalysed oxidative esterification of aldehydes using a H2O2 trapped oxidant as a terminal oxidant
Gayakwad, Eknath M.,Patil, Vilas V.,Shankarling, Ganapati S.
, p. 2695 - 2701 (2017/04/03)
A simple and efficient method has been developed for the selective oxidative esterification of aldehydes using commercially available Amberlyst-15 as a catalyst. H2O2 released from a clathrate structured 4Na2SO4·2H2O2·NaCl oxidant serves as an efficient source of terminal oxidants. Various aromatic, heteroaromatic, and aliphatic aldehydes undergo selective esterification to give good to excellent yield. The heterogeneous catalyst, Amberlyst-15, exhibits high reactivity and can be recycled over several runs. The 4Na2SO4·2H2O2·NaCl oxidant was found to be superior to commonly used oxidizing agents providing an anhydrous, easy to handle and stable form of H2O2
