- The First 1-Hydroxypropylidenebisphosphonic Acid with 1,8-Naphthyridinone Substituent: Synthesis and Structure
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1-Hydroxy-3-(5,7-dimethyl-2-oxo-1,2-dihydro-1,8-naphthyridin-1-yl)propylidenebisphosphonic acid has been synthesized. The structure of the acid and its precursors synthesized for the first time, 3-(5,7-dimethyl-2-oxo-1,2-dihydro-1,8-naphthyridin-1-yl)propionic acid and the corresponding methyl ester, in the solid state and in the DMSO solution has been elucidated by means of vibrational (IR and Raman) and multinuclear (1H, 13C, and 31P) NMR spectroscopy.
- Bodrin,Pasechnik,Matveeva,Aysin,Matveev,Goryunov,Strelkova,Brel
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- Intense one- and two-photon excited fluorescent Bis(BF2) core complex containing a 1,8-naphthyridine derivative
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The first bis(BF2) core complex containing a 1,8-naphthyridin derivative (1,2-bis(5,7-dimethyl-1,8-naphthyridin-2-yl)hydrazine) and with yellow-green emission as well as a high quantum yield was synthesized and structurally characterized, and the compound exhibits two-photon absorption and excited fluorescence properties.
- Li, Huifang-Jie,Fu, Wen-Fu,Li, Li,Gan, Xin,Mu, Wei-Hua,Chen, Wei-Qiang,Duan, Xuan-Ming,Song, Hai-Bin
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- 1,8-Naphthyridine-Derived Ni2+/Cu2+-Selective fluorescent chemosensor with different charge transfer processses
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A highly fluorescent chemosensor based on 1,8-naphthyridine with high sensitivity and selectivity toward Ni2+/Cu2+ over other cations both in aqueous solution over a wide pH range (4-10) and in cellular environments was developed. Counteranions such as acetate, sulfate, nitrate, and perchlorate have no influence on the detection of such metal ions. Ethylenediamine showed high selectivity toward the in situ-prepared Cu 2+ complex over the Ni2+ complex, which can be applied to distinguish Ni2+ and Cu2+. The Ni2+-induced fluorescence on-off mechanism was revealed to be mediated by intramolecular charge transfer from the metal to the ligand, while that by Cu2+ involves intramolecular charge transfer from the ligand to the metal, as confirmed by picosecond time-resolved fluorescence spectroscopy and time-dependent density functional theory calculations.
- Li, Zhanxian,Zhao, Wanying,Li, Xiaoya,Zhu, Yanyan,Liu, Chunmei,Wang, Lina,Yu, Mingming,Wei, Liuhe,Tang, Mingsheng,Zhang, Hongyan
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- A reversible fluorescent chemosensor for the rapid sensing of CN- in water: Utilization of the intramolecular charge transfer blocking
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A reversible and water-soluble 2,4-dimethyl-7-amino-1,8-naphthyridine (ZR) was synthesized to fluorescently sense CN- in water. Interestingly, the deprotonation reaction between cyanide and the primary amine would block the intramolecular charge transfer of the electron donor and acceptor, thus, affecting the ICT efficiency and optical properties of the sensing system.
- Wei, Tai-Bao,Zhu, Yuan-Rong,Li, Hui,Yan, Guo-Tao,Lin, Qi,Yao, Hong,Zhang, You-Ming
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- Synthesis, structures and spectroscopic properties of new 1,2-bis[2-(4-methyl-7-acetylamino-1,8-naphthyridine)]ethylene ligand and its binuclear copper(I) complexes
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The synthesis, characterization, spectroscopic properties of a new ligand 1,2-bis[2-(4-methyl-7-acetylamino-1,8-naphthyridine)]ethylene (L) and its two binuclear Cu(I) complexes containing triphenylphosphine (PPh3) or bis(diphenylphosphino)methane (dppm), [Cu2(L)(PPh3) 4](BF4)2·2CH2Cl2 (1·2CH2Cl2) and [Cu2(L)(dppm) 2](BF4)2·4H2O (2·4H2O) are reported. The structural investigation of these compounds based on X-ray crystal analysis shows that the copper(I) centers adopt different coordination geometries, O(N)CuP2+ and NCuP2+ for complexes 1 and 2, respectively. Upon irradiation of a degassed organic solution of L at 365 nm, photoinduced isomerization reaction and an intramolecular proton transfer of ligand L were detailed studied by absorption spectral changes. A spectroscopic investigation involving time-dependent density functional theory calculations allows assignment of the excited states that relate to emission and transient absorption spectra. The observed lower-energy absorption bands appearing in the region of 413 and 418 nm for 1 and 2 in dichloromethane are assigned to ligand-to-ligand charge transfer (LLCT, phosphine → napy) transition in nature. Compared with well-structured solid-state emission originating from ππ transition of ligand L, complexes 1 and 2 exhibit intense room-temperature solid-state emissions with λmax at 586 and 620 nm, respectively. The energy and the shape of the emission bands are clearly different from that of the ligand, indicating the emissions come from different excited states.
- Li, Zhan-Xian,Li, Cong,Mu, Wei-Hua,Xiong, Shao-Xiang,Fu, Wen-Fu
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- A novel Schiff-base fluorescent probe based on 1,8-naphthyridine and naphthalimide for Al3+
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A novel Schiff-base, 7-acetamino-4-methyl-1,8-naphthyridine-2-carbaldehyde-(1′,8′-naphthalenedicarbonyl) hydrazone (HL) was designed, synthesized and evaluated as a fluorescent probe. The fluorescence properties of this probe towards various metal ions were investigated by UV–vis and fluorescence spectra in methanol. Test results indicated that the probe had high selectivity towards Al3+ over other commonly coexisting metal ions. Upon addition of Al3+, the fluorescence intensity at 414?nm increased significantly due to the inhibition of the PET process. The binding constant (Ka) of Al3+ binding to HL was calculated to be 5.64?×?104?M?1 from a Benesi-Hildebrand plot, and the detection limit (LOD) of HL for sensing Al3+ was calculated to be 0.13?μM. The binding stoichiometry between HL and Al3+ was determined as 1:1 by the Job's plot. Furthermore, the probe was chemically reversible for Al3+ in methanol by the addition of Na2EDTA solution.
- Yue, Xiao-li,Li, Chao-rui,Yang, Zheng-yin
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- COMPOUNDS AND METHODS FOR ENHANCING INNATE IMMUNE RESPONSES
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Provided are certain compounds and pharmaceutically acceptable salts thereof, their pharmaceutical compositions, their methods of preparation, and their use for treating viral infections.
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Paragraph 00240
(2013/05/09)
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- Synthesis and evaluation of fluorogenic 2-amino-1,8-naphthyridine derivatives for the detection of bacteria
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Several novel fluorogenic N-aminoacylnaphthyridine substrates were synthesized in good yield and tested for their ability to detect pathogenic bacteria in agar-based cell culture. Simple 2-N-(β-alanyl)amino-5,7- dialkylnaphthyridine substrates were selectively hydrolysed by β-alanylaminopeptidase expressing bacteria, but were subject to diffusion in the agar medium. Diffusion was reduced in the 2-N-(β-alanyl)amino-7- alkylnaphthyridine substrates with longer alkyl chains, but inhibition of growth was increased. 2-N-(β-Alanyl)amino-7-octylnaphthyridine inhibited the growth of all species tested, except for strains resistant to colistin/polymyxin, providing a rationale for the development of substrates for the selective detection of drug resistant species in clinical samples. The Royal Society of Chemistry 2012.
- Varadi, Linda,Gray, Mark,Groundwater, Paul W.,Hall, Andrew J.,James, Arthur L.,Orenga, Sylvain,Perry, John D.,Anderson, Rosaleen J.
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experimental part
p. 2578 - 2589
(2012/04/23)
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- Syntheses and structure characterization of four inorganic-organic hybrid solids based on N-containing aromatic Brnsted bases and chlorometallates
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Four organic-inorganic hybrid complexes ([(HL1)2SnCl 6]·2H2O (1) (L1=2-methylquinoline), [(HL2) 2(CdCl4)]·2H2O (2) (L2=5,7-dimethyl-1,8- naphthyridine-2-amine), [(H2L2)2SnCl6]2(Cl) (3), and [(H2L3)SnCl6]·2H2O (4) (L3=3,6-bis(imidazol-1-yl)pyridazine)) derived from N-containing aromatic Brnsted bases and metal(II) chloride dihydrate (tin(II) chloride dihydrate and cadmium(II) chloride dihydrate) were prepared and characterized by IR, X-ray structure analysis, elemental analysis, and TG analysis. The aromatic rings of the cations in all of the compounds are essentially planar. X-ray diffraction analysis revealed that 2-4 have 3-D network structures built from hydrogen bonds between the cations and chlorometallates. Water molecules also play important roles in structure extension in 1, 2, and 4. The arrangements of the anions and cations in their solid state are dominated by shape, size, and symmetry of the cations and the different structures of the chlorometallates as well as by hydrogen-bond interactions.
- Jin, Shouwen,Wang, Daqi
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experimental part
p. 1937 - 1952
(2012/09/22)
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- Large stokes shift induced by intramolcular charge transfer in N,O-chelated naphthyridine-BF2 complexes
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Novel N,O-chelated naphthyridine-BF2 complexes with push-pull structures have been synthesized and characterized. Spectral investigations on these complexes reveal that photoinduced intramolecular charge transfer occurs and results in a large Stokes shift, which is further supported by density functional theory based theoretical calculations.
- Wu, Yun-Ying,Gou, Gao-Zhang,Mu, Wei-Hua,Du, Mei-Ling,Fu, Wen-Fu,Chen, Yong,Lv, Xiao-Jun
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supporting information
p. 5226 - 5229,4
(2012/12/13)
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- Cu(I) and Pb(II) complexes containing new tris(7-naphthyridyl)methane derivatives: Synthesis, structures, spectroscopy and geometric conversion
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Two novel facial-capping tris-naphthyridyl compounds, 2-chloro-5-methyl-7- ((2,4-dimethyl-1,8-naphthyridin-7(1H)-ylidene)(2,4-dimethyl-1, 8-naphthyridin-7-yl))methyl-1,8-naphthyridine (L1) and 2-chloro-7-((2-methyl-1,8-naphthyridin-7(1H)-ylidene)(2-methyl-1, 8-naphthyridin-7-yl))methyl-1,8-naphthyridine (L2), as well as their Cu(I) and Pb(II) complexes, [CuLa(PPh3)]BF4 (1) (PPh3 = triphenylphosphine, La = bis(2,4-dimethyl-1,8- naphthyridin-7-yl)(2-chloro-5-methyl-1,8-naphthyridin-7-yl)methane), [CuL b(PPh3)]BF4 (2) (Lb = bis(2-methyl-1,8-naphthyridin-7-yl)(2-chloro-1,8-naphthyridin-7-yl)methane), [Pb(OLa)(NO3)2] (3) (OLa = bis(2,4-dimethyl-1,8-naphthyridin-7-yl)(2-chloro-5-methyl-1,8-naphthyridin-7-yl) methanol) and [Pb(Lb)2][Pb(CH3OH)(NO 3)4] (4), have been synthesized and characterized by X-ray diffraction analysis, MS, NMR and elemental analysis. The structural investigations revealed that the transfer of the H-atom at the central carbon to an adjacent naphthyridine-N atom affords L1 and L2 possessing large conjugated architectures, and the central carbon atoms adopt the sp2 hybridized bonding mode. The reversible hydrogen transfer and a geometric configuration conversion from sp2 to sp3 of the central carbon atom were observed when Pb(II) and Cu(I) were coordinated to L1 or L2. The molecular energy changes accompanying the hydrogen migration and titration of H+ to different receptor-N at L1 were calculated by density functional theory (DFT) at the SCRF-B3LYP/6-311++G(d,p) level in a CH2Cl2 solution, and the observed lowest-energy absorption and emission for L1 and L 2 can be tentatively assigned to an intramolecular charge transfer (ICT) transition in nature.
- Gan, Xin,Chi, Shao-Ming,Mu, Wei-Hua,Yao, Jia-Can,Quan, Li,Li, Cong,Bian, Zhao-Yong,Chen, Yong,Fu, Wen-Fu
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scheme or table
p. 7365 - 7374
(2011/09/14)
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- Synthesis of a novel tripodal receptor based on 1,8-naphthyridine derivatives
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A novel tripodal receptor, 1,3,5-tri((5,7-dimethyl-1,8-naphthyridin-2-yl-amino)methyl)-2,4,6-triethylbenzene (1) was synthesized from starting materials 2,6-diamino-pyridine (2) and 1,3,5-triethylbenzene (4) by three steps with an overall yield of 25%, and characterized by ESI-MS, FT-IR and 1H NMR spectra. Additionally, its absorption and emission spectra were investigated.
- Li, Hui Fang Jie,Fu, Wen Fu
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scheme or table
p. 23 - 26
(2010/11/17)
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- Synthesis, characterization, photoinduced isomerization, and spectroscopic properties of vinyl-1,8-naphthyridine derivatives and their copper(I) complexes
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A series of 1,8-naphthyridine derivatives containing vinyl, 2-(2-acetylamino-pyridine-6-ethylene)-4-methyl-7-acetylamino-1,8-naphthyridine (L1), 2-(2-acetylamino-pyridine-6-ethylene)-1,8-naphthyridine (L 2), 2-(2-acetylamino-pyridinyl-6-ethylene)-4-methyl-7-hydroxyl-1,8- naphthyridine (L3), 2-(2-diacetylamino-pyridinyl-3-ethylene)-7- diacetylamino-1,8-naphthyridine (L4), and 7-(2-diacetylamino- pyridinyl-3-ethylene)-4′-acetyl-pyrrolo[1′,5′-a]-1, 8-naphthyridine (L5), as well as complexes [CuL1(PCy 3)](BF4)2 (1) (PCy3 = tricyclohexylphosphine), [Cu2L1(PPh3) 4](BF4)2 (2) (PPh3 = triphenylphosphine), [Cu2L1(dppm)](BF4) 2 (3) (dppm = bis(diphenylphosphino)methane), and [Cu 2(L1)(dcpm)][BF4]2 (4) (dcpm = bis(dicyclohexylphosphino)methane, were synthesized. All these compounds, except for L1 and L2, were characterized by single crystal X-ray diffraction analysis, and a comprehensive study of their spectroscopic properties involving experimental theoretical studies is presented. We found an intramolecular 1,3-hydrogen transfer during the formation of L3 and L4, which in the case of the latter plays an important role in the 1,5-dipolar cyclization of L5. The spectral changes that originate from an intramolecular charge transfer (ICT) in the form of a πpy→π*napy transition can be tuned through acid/base-controlled switching for L1-L3. A photoinduced isomerization for L1-L3, 1, and 2 having flexible structures was observed under 365 nm light irradiation. Quantum chemical calculations revealed that the dinuclear complexes with structural asymmetry exhibit different metal-to-ligand charge-transfer transitions.
- Fu, Wen-Fu,Jia, Lin-Fang,Mu, Wei-Hua,Gan, Xin,Zhang, Jia-Bing,Liu, Ping-Hua,Cao, Qian-Yong,Zhang, Gui-Ju,Quan, Li,Lv, Xiao-Jun,Xu, Quan-Qing
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scheme or table
p. 4524 - 4533
(2010/07/04)
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- A "switching on" fluorescent chemodosimeter of selectivity to Zn2+ and its application to MCF-7 cells
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A highly sensitive and selective 1,8-naphthyridine-based fluorescent chemodosimeter for Zn2+ has been designed, synthesized, and applied to the detection of intracellular Zn2+.
- Li, Zhanxian,Yu, Mingming,Zhang, Lifeng,Yu, Ming,Liu, Jinxia,Wei, Liuhe,Zhang, Hongyan
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supporting information; experimental part
p. 7169 - 7171
(2010/11/04)
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- Substituted -6,7,8,9-tetrahydro-pyrido- and 2H-pyrano [2,3-b][1,8]naphthyridines, stable efficient laser dyes
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Compounds having the formula: STR1 wherein X is selected from the group consisting of NH and O, R is selected from the group consisting of H, CH3 and phenyl, R' is selected from the group consisting of OCH3, CF3 CH3 and H and R" is selected from the group consisting of H, CH3 and CH2 CO2 C2 H5. The compounds are stable, efficient laser dyes.
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- 1,4-Dithiino(2,3-c)pyrrole derivatives
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New compounds of the formula: SPC1 Wherein A is a phenyl, pyridyl, pyridazinyl, 2-, 3- or 4-quinolyl or naphthyridinyl radical, or a said radical substituted by one or two atoms or radicals selected from halogen, alkyl, alkoxy cyano and nitro, R is alkyl, alkenyl or hydroxyalkyl, and n is zero or 1, possess pharmacological properties and are, in particular, active as tranquilisers, anti-convulsant agents, decontracturants and agents to produce hypnosis.
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