- 2-D lanthanide-organic complexes constructed from 6,7-dihydropyrido(2,3-d) pyridazine-5,8-dione: Synthesis, characterization and photoluminescence for sensing small molecules
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Four isostructural lanthanide-organic complexes [Ln(HPDH)(ox)(H 2O)]n (Ln = Eu3+1, Tb3+2, Sm 3+3, Gd3+4; H2PDH = 6,7-dihydropyrido(2,3-d) pyridazine-5,8-dione; H2ox = oxalic acid) have been synthesized successfully under hydrothermal conditions and characterized by means of elemental analysis, powder XRD, TG-DTA, IR and UV-vis spectroscopy. Complexes 1 and 2 were structurally characterized by single crystal X-ray diffraction analysis. All complexes are composed of 2-D layers, which further construct a 3-D supramolecular network. Each 2-D layer in complexes 1-4 is composed of 1-D Eu-ox infinite chains, which are further connected by biconnected HPDH - ligands. The photoluminescent properties of complexes 1-4 were studied in the solid state at room temperature. The singlet energy level (34722 cm-1) and the lowest triplet energy level (21786 cm-1) for the ligand H2PDH were calculated on the basis of its UV-vis absorbance edges (1 × 10-4 M in ethanol) and phosphorescence spectrum of complex 4 at 77 K, respectively. The complexes 1, 2, and 3 exhibit metal centered luminescence with characteristic red, green and pink emission, respectively. The energy transfer mechanism and photoluminescence properties were investigated. Complex 1, in which the energy transition from the triplet energy level (3ππ*) of ligand HPDH- to Eu3+ cation is more effective, has been selected as a representative to examine the potential for sensing small molecules by its luminescence properties in different emulsions. EtOH was found to be an excellent enhancing while DMF a highly quenching solvent in this study.
- Ahmad, Waqar,Zhang, Lijuan,Zhou, Yunshan
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- A series of mononuclear lanthanide complexes featuring 3-D supramolecular networks: Synthesis, characterization and luminescent properties for sensing guest molecules
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A new series of four isostructural mononuclear lanthanide complexes Ln(HPDH)3(H2O)3·H2O (Ln = Sm(iii) 1, Eu(iii) 2, Tb(iii) 3 and Dy(iii) 4; H2PDH = 6,7-dihydropyrido(2,3-d)pyridazine-5,8-dione) has been prepared and characterized by IR, elemental analysis, XRD and TG-DTA methods. Single crystal X-ray diffraction analysis of both complexes 1 and 3 revealed that the mononuclear discrete complexes form 3-D supramolecular networks via hydrogen bonds and offset stacking (-H...π) interactions. The photoluminescence study of the title complexes revealed the photoluminescent potential of the antenna ligand (H2PDH) toward the concerned lanthanide cations. The luminescence based sensing ability of the partially dehydrated complex Tb(HPDH)3(H2O)33a towards small solvent molecules, along with its reusability, has been studied. Isopropyl alcohol was found to be an excellent sensitizer, while tetrahydrofuran was a highly quenching solvent with a first order behavior towards the photoluminescence intensity. The photoluminescence intensity was found to decrease with the increase of the dielectric constant and normalized Dimroth-Reichardt E T parameter values for protic solvents, while reverse behavior was observed for dipolar aprotic solvents.
- Ahmad, Waqar,Zhang, Lijuan,Zhou, Yunshan
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- KRAS G12C INHIBITORS AND METHODS OF USING THE SAME
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Provided herein are KRAS G12C inhibitors, composition of the same, and methods of using the same. These inhibitors are useful for treating a number of disorders, including pancreatic, colorectal, and lung cancers.
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Paragraph 0306
(2018/07/29)
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- KRAS G12C INHIBITORS AND METHODS OF USING THE SAME
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Provided herein are KRAS G12C inhibitors, composition of the same, and methods of using the same. These inhibitors are useful for treating a number of disorders, including pancreatic, colorectal, and lung cancers.
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Paragraph 0529
(2018/12/04)
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- KRAS G12C INHIBITORS AND METHODS OF USING THE SAME
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Provided herein are KRAS G12C inhibitors, composition of the same, and methods of using the same. These inhibitors are useful for treating a number of disorders, including pancreatic, colorectal, and lung cancers.
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- 1, 2, 3, 4- [...] compound and process for the synthesis of
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The invention provides a synthetic and technological method of a 1,2,3,4-tetrahydrophthalazine compound used as an intermediate of bactericides and anti HIV (human immunodeficiency virus) and other new drugs. The 1,2,3,4-tetrahydrophthalazine compound is obtained by using various cheap and easily accessible phthalic acid or phthalic anhydride as a raw material for two steps of reaction. The method is easily accessible in raw material, low in cost, simple in reaction, easy in control, simple in processing and easy in amplification, and a large number of industrial by-product hydrazide can be found to be directly used as a raw material for the second step. The method is convenient to economic, reuses the industrial by-product as the raw material, and provides a feasible synthetic production and technological method of the 1,2,3,4-tetrahydrophthalazine compound for green chemical industry.
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- Design, synthesis of 6-substituted-pyrido[3,2-d]pyridazine derivatives with anticonvulsant activity
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Aim to find new compounds with stronger anticonvulsant activity and lower neurotoxicity, a novel series of 6-substituted-pyrido[3,2-d]pyridazine derivatives was synthesized using furo[3,4-b]pyridine-5,7-dione as the starting material. We evaluated their a
- Dong, Zheng-Qi,Liu, Xiao-Mei,Wei, Cheng-Xi,Quan, Zhe-Shan
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p. 595 - 601
(2015/08/18)
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- Addressing PXR liabilities of phthalazine-based hedgehog/smoothened antagonists using novel pyridopyridazines
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Pyridopyridazine antagonists of the hedgehog signaling pathway are described. Designed to optimize our previously described phthalazine smoothened antagonists, a representative compound eliminates a PXR liability while retaining potency and in vitro metab
- Kaizerman, Jacob A.,Aaron, Wade,An, Songzhu,Austin, Richard,Brown, Matt,Chong, Angela,Huang, Tom,Hungate, Randall,Jiang, Ben,Johnson, Michael G.,Lee, Gary,Lucas, Brian S.,Orf, Jessica,Rong, Minqing,Toteva, Maria M.,Wickramasinghe, Dineli,Xu, Guifen,Ye, Qiuping,Zhong, Wendy,McMinn, Dustin L.
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scheme or table
p. 4607 - 4610
(2010/10/02)
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- ANNELATED PYRIDAZINES FOR THE TREATMENT OF TUMORS DRIVEN BY INAPPROPRIATE HEDGEHOG SIGNALLING
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The present invention relates generally to compounds represented in Formula (I), pharmaceutical compositions comprising them and methods of treating of diseases or disorders such as cancer.
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Page/Page column 77
(2009/04/25)
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- Pentaaza-cyclopental[a]naphthalene derivatives as ligands for GABAa α5 receptors
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A class of 1,2,3a,4,x-pentaaza-cyclopenta[a]naphthalene compounds (x=6, 7, 8 or 9) is described. The compounds have a high affinity for the GABAAα5 receptors and show inverse agonist activity thereat. The compounds are useful in therapy where cognition enhancement is required.
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- New synthesis of pyrido[2,3-d] and [3,2-d]oxazines
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N-Hydroxyquinolinimide 1 reacts with each of aromatic arnines, hydrazine hydrate and aromatic hydrocarbons to give arylcarbamoyl pyridines 2, pyrrolopyridines 3, pyridopyridazines 4 and pyridooxazinones 5 and 6. The heterocycles 5 and 6 can be transformed
- Fahmy, Amin F.,Sauer, Juergen,Youssef, Mohamed Salah K.,Halim, Mohamed Said Abdel,Hassan, Mamdouh A.
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p. 2871 - 2886
(2007/10/03)
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- Method of quantitative determination of peroxide, a peroxidation-active substance or a pyrazolopyridopyridazine derivative
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Disclosed is a chemiluminescent method of quantitatively determining one of peroxide, a peroxidation-active substance or a pyrazolopyridopyridazine derivative represented by the formula (I): wherein R1represents hydrogen, lower alkyl, optionally substituted aryl, optionally substituted heterocyclic group, substituted sulfonyl, substituted sulfinyl, substituted thio etc.; R2represents hydrogen, lower alkyl, optionally substituted aryl, etc., or a salt thereof;, characterized by subjecting an unknown amount of one substance selected from the peroxide, peroxidation-active substance and pyrazolopyridopyridazine derivative to react with a known amount of the remaining two substances.
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- Mechanistic Aspects of Diazaquinone Chemiluminescence
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Twelve cyclic hydrazides of aromatic and heterocyclic o-dicarboxylic acids were converted into diazaquinones by treatment with t-butyl hypochlorite.Chemiluminescence was produced from all diazaquinones on treatment with HO2- derived from hydrogen peroxide and potassium hydroxide.Diazaquinones derived from pyridine and pyrazine o-dicarboxylic acid hydrazides afforded chemiluminescence with hydrogen peroxide alone.Such nitrogen bases and N-oxides increase the nucleophilicity of hydrogen peroxide by complex formation and this effect was also exemplified by observation of chemiluminescence from phthalazine-1,4-diones, hydrogen peroxide and either pyridine or pyridine N-oxide.Highly reactive diazaquinones emit light with aqueous alkali and oxygen.No chemiluminescence was produced with organic bases and oxygen which suggests the involvement of a different mechanism compared with the hydroperoxide anion case.
- Paul, D. Brenton
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p. 1001 - 1008
(2007/10/02)
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- Benzocyclobutenes. Part 4. Synthesis of Benzocyclobutene-1,2-diones by Pyrolytic Methods
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Oxidation of the cyclic hydrazides prepared from phthalic anhydrides in the presence of anthracene gives the corresponding Diels-Alder adducts which, on flash vacuum pyrolysis, give benzocyclobutene-1,2-dione (BBD) and its 4-chloro, 3,6- and 4,5-dichloro, 4,5-dibromo, and 4,5-dimethyl derivatives in 75-98percent yield.Cyclobuta- and cyclobuta-naphthalene-1,2-dione as well as cyclobuta- and cyclobuta-pyridine-1,2-dione have been prepared similarly; the last three of these diones are very unstable.Cyclobutanaphthalene-1,2-dione has also been made by pyrolysis of benzindene-1,2,3-trione.Attempts to make thiophen and furan analogues of BBD from appropriate anthracene adducts failed as did attempts to make tetrachloro- and tetrabromo-derivatives of BBD by the pyrolysis of tetrahalogenophthalimidosulphoximides.
- Gould, Ken J.,Hacker, Nigel P.,McOmie, John F. W.,Perry, David H.
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p. 1834 - 1840
(2007/10/02)
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