106047-17-0Relevant articles and documents
Upgrading malic acid to bio-based benzoates via a Diels-Alder-initiated sequence with the methyl coumalate platform
Lee, Jennifer J.,Pollock Iii, Gerald R.,Mitchell, Donald,Kasuga, Lindsay,Kraus, George A.
, p. 45657 - 45664 (2014)
The conversion of naturally-occurring malic acid to the 2-pyrone methyl coumalate was optimized using a variety of acid catalysts. Coupling methyl coumalate with electron-rich dienophiles in an inverse electron-demand Diels-Alder (IEDDA)/decarboxylation/elimination domino sequence resulted in an investigation of the scope and limitations of the methodology. The thermal, metal-free, and one-pot procedure allows regioselective access to diverse aromatic compounds including tricyclic, biphenyl, and pyridinyl systems for elaboration. A comparison with analogous pyrones demonstrates the striking efficacy of methyl coumalate as a versatile platform for the generation of biorenewable functionalized benzoates. This journal is
An Indefinitely Air-Stable σ-NiII Precatalyst for Quantitative Cross-Coupling of Unreactive Aryl Halides and Mesylates with Aryl Neopentylglycolboronates
Malineni, Jagadeesh,Jezorek, Ryan L.,Zhang, Na,Percec, Virgil
, p. 2795 - 2807 (2016)
Three classes of Ni precatalysts based on π-NiII, π-Ni0 and σ-NiII complexes have been elaborated and employed in different laboratories for the functionalization and cross-coupling of otherwise inert aryl C-O, C-Cl, and C-F electrophiles. Various Ni precatalysts, ligands, boron sources, and reaction conditions that were developed in various research groups, necessitated the selection of the most suitable conditions for desired cross-coupling partners. Here a universal, bench-stable, easily prepared NiIICl(1-naphthyl)(PCy3)2/PCy3 σ-complex, for efficient and quantitative cross-coupling of aryl chlorides, bromides, iodides, mesylates, and fluorides with aryl neopentylglycolboronates is reported. This precatalyst will most probably help to advance the applications of Ni catalysis in organic, supramolecular, and macromolecular synthesis and will provide an easier access to the selection of reaction conditions for various transformations.
A convenient synthesis of methyl 4-substituted benzoates via Diels-Alder reaction in the presence of palladium on activated carbon
Matsushita,Sakamoto,Murakami,Matsui
, p. 3307 - 3313 (1994)
The thermal reaction of methyl 2-oxo-2H-pyran-5-carboxylates with substituted styrenes in the presence of 10% palladium on activated carbon afforded directly the corresponding methyl 4-biphenylcarboxylates in good yields. By the similar procedure, methyl 4-heteroaryl- and 4-alkyl-substituted benzoates were obtained from heteroaromatic olefines and alkenes, respectively.
Acylhydrazone as a novel off-On-Off fluorescence probe for the sequential detection of Al3+ and F-
Wu, Yi-Peng,Rahman, Faiz-Ur,Bhatti, Muhammad Zeeshan,Yu, Shang-Bo,Yang, Bo,Wang, Hui,Li, Zhan-Ting,Zhang, Dan-Wei
, p. 14978 - 14985 (2018)
A new acylhydrazone fluorescence probe, SPBH, was synthesized from salicylaldehyde and 4-(pyridin-4-yl)benzohydrazide (PBH). SPBH exhibited high selectivity and a sensitive fluorescence response towards Al3+, even in the presence of other competing metal ions in DMF/H2O (1:1, v/v) medium. And, the chemosensor can even detect Al3+ in the intracellular region of human non-small cell lung cancer H460 cells. The binding phenomenon of SPBH was investigated by 1H NMR spectroscopy and HR-MS. Mass spectrometry analysis showed a 1:1 complex formation of SPBH with Al3+. The Job plot also confirmed its 1:1 interaction. This SPBH/Al3+ complex exhibited excellent fluorescence turn-off properties towards the F- anion. Thus, SPBH acts as a sequential fluorescence Off-On-Off probe. The limits of detection for Al3+ and F- were calculated from the titration curve and found to be 1.1 × 10-7 M and 1.47 × 10-6 M, respectively.
Palladium-Catalyzed Electrophilic Functionalization of Pyridine Derivatives through Phosphonium Salts
Che, Yuan-Yuan,Deng, Xuezu,Feng, Chao,Lin, Ling-Zhi,Pei, Bingbing,Yue, Yanni
supporting information, p. 16414 - 16419 (2020/07/20)
Herein, we report a highly efficient and practical method for pyridine-derived heterobiaryl synthesis through palladium-catalyzed electrophilic functionalization of easily available pyridine-derived quaternary phosphonium salts. The nice generality of this reaction was goes beyond arylation, enabling facile incorporation of diverse carbon-based fragments, including alkenyl, alkynyl, and also allyl fragments, onto the pyridine core. Notably, the silver salt additive is revealed to be of vital importance for the success of this transformation and its pivotal role as transmetallation mediator, which guarantees a smooth transfer of pyridyl group to palladium intermediate, is also described.
Experimental and density functional theory insights into the effect of withdrawing ligands on the fluorescence yield of Ru(II)-based complexes
Ali, Basant A.,Sharmoukh, Walid,Elnagar, Mohamed M.,Hassan, Zeinab M.,Allam, Nageh K.
, (2018/12/14)
The quality of emission spectra of metal complexes gives good insights into their performance in many optoelectronic applications. Herein, the effect of the number and position of various ligand structures on the emission spectra of Ru bipyridine complexes was studied. Specifically, the use of a different number of withdrawing groups (COOH) was investigated in detail. The complexes were first investigated using density functional theory (DFT) and time-dependent DFT calculations and then confirmed experimentally. The bandgap energy, reactivity, emission spectra and Stokes shift were found to depend on the number and position of the withdrawing groups attached to the Ru(bpy)22+ complexes. Upon increasing the number of withdrawing groups, the electrons were found to be withdrawn from the carbon orbitals and resonated to reach the metal, and accumulated around it, thus enhancing the metal-to-ligand charge transfer mechanism instead of the ligand-to-ligand charge transfer mechanism. The complexes with more withdrawing groups showed spectra with more intense emission peaks with shorter lifetime, indicating the enhancement in the photoactivity of the complexes. Ligands with ring nitrogens with two COOH groups showed the greatest effect on the enhancement of the emission spectra with a lifetime of 0.5359?ns. The resulting collective emission spectra covered a wide wavelength range, making the investigated complexes a good choice for many optoelectronic applications.
PYRROLOPYRIMIDINE COMPOUNDS USED AS TLR7 AGONIST
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Paragraph 0101, (2017/07/29)
The present invention relates to a pyrrolopyrimidine compound as TLR7 agonist, and particularly relates to a compound of formula (I) or a pharmaceutically acceptable salt thereof, a preparation process thereof, a pharmaceutical composition containing such compounds and use thereof for manufacturing a medicament against viral infection.
Pyrrolo pyrimidine ring compound, its use and pharmaceutical composition (by machine translation)
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Page/Page column 50; 51, (2017/07/31)
The invention relates to an as TLR7 agonist of the pyrrolo pyrimidine compounds, specifically on a compound of formula (I) compound or its pharmaceutically acceptable salt, preparation method thereof, containing the compounds of the pharmaceutical composition, and its use for the preparation of antiviral drug use. Formula (I) (by machine translation)
Discovery and mechanism study of SIRT1 activators that promote the deacetylation of fluorophore-labeled substrate
Wu, Jiahui,Zhang, Dengyou,Chen, Lei,Li, Jianneng,Wang, Jianling,Ning, Chengqing,Yu, Niefang,Zhao, Fei,Chen, Dongying,Chen, Xiaoyan,Chen, Kaixian,Jiang, Hualiang,Liu, Hong,Liu, Dongxiang
, p. 761 - 780 (2013/04/10)
SIRT1 is an NAD+-dependent deacetylase, whose activators have potential therapeutic applications in age-related diseases. Here we report a new class of SIRT1 activators. The activation is dependent on the fluorophore labeled to the substrate. To elucidate the activation mechanism, we solved the crystal structure of SIRT3/ac-RHKKac-AMC complex. The structure revealed that the fluorophore blocked the H-bond formation and created a cavity between the substrate and the Rossmann fold. We built the SIRT1/ac-RHKK ac-AMC complex model based on the crystal structure. Km and Kd determinations demonstrated that the fluorophore decreased the peptide binding affinity. The binding modes of SIRT1 activators indicated that a portion of the activators interacts with the fluorophore through π-stacking, while the other portion inserts into the cavity or interacts with the Rossmann fold, thus increasing the substrate affinity. Our study provides new insights into the mechanism of SIRT1 activation and may aid the design of novel SIRT1 activators.
Nickel-catalyzed cross-coupling of phenols and arylboronic acids through an in situ phenol activation mediated by PyBroP
Chen, Guo-Jun,Huang, Jie,Gao, Lian-Xun,Han, Fu-She
supporting information; experimental part, p. 4038 - 4042 (2011/05/05)
A new method for the Suzuki-Miyaura cross-coupling of phenols and arylboronic acids through in situ phenol activation mediated by PyBroP is presented. The reaction proceeds efficiently by using cost-effective, markedly stable [NiCl2(dppp)] (dppp=1,3-bis(diphenylphosphino)propane) as the catalyst in only 5 mol % loading, as well as in the absence of extra ligands. The method exhibits broad applicability and high efficiency towards a wide range of both phenols and boronic acids, including activated, nonactivated, deactivated, and heteroaromatic coupling partners. In addition, various functional groups, such as ether, amino, cyano, ester, and ketone groups, are compatible with this transformation. Notably, arylboronic acids containing an unprotected NH2 group and 2-heterocyclic boronic acids, which are generally problematic for coupling under conventional conditions, are also viable substrates, although moderate yields were obtained for sterically hindered substrates. Consequently, the in situ cross-coupling methodology coupled with the use of an inexpensive and stable nickel catalyst provides a rapid and efficient pathway for the assembly of biaryls and heterobiaryls with structural diversity from readily available phenol compounds.
