- Photoluminescence performance of green light emitting terbium (III) complexes with β-hydroxy ketone and nitrogen donor ancillary ligands
-
An efficient and cost-effective technique, solution precipitation approach is adopted to synthesize five bright green luminescent terbium (III) complexes by employing the main β-hydroxy ketone ligand, 2-hydroxy-4-ethoxyacetophenone, and ancillary ligands like bathophenanthroline, 5,6-dimethyl-1,10-phenanthroline, 1,10-phenanthroline, and 2,2-bipyridyl. The elemental compositions and binding mode of ligand to terbium (III) ion can be validated by using energy dispersive X-ray analysis, elemental analysis, Fourier transform infrared, and proton nuclear magnetic resonance spectroscopy. The complexes are thermally stable up to 158°C and possess the cubic shaped particles as confirmed by thermogravimetric analysis and scanning electron microscopic study, respectively. The band-gap energy (3.02–2.92 eV) of complexes is reckoned through diffuse reflectance spectra, which tailors them as potential candidates in the field of military radars. The photoluminescence studies unveil that the complexes exhibit the bright green luminescence corresponding to 5D4 → 7F5 transition of Tb3+ ion (548 nm) under the excitation wavelength of 395 or 397 nm. The Commission International de I’Eclairage chromaticity coordinates (x, y) and color purity substantiates the green emission of complexes. The energy transfer mechanism elucidates that the main ligand and ancillary ligands sensitize Tb3+ ion, which in turn enhances the luminescence efficiency of the emissive layer of white organic light emitting diodes. The results reveal that the complexes are considered as good contenders in the field of display devices and laser technology. Lastly, in vitro antimicrobial and antioxidant activity proclaim the potent antimicrobial and antioxidant actions of complexes via tube dilution and 2, 2-diphenyl-1-picrylhydrazyl assays, respectively.
- Khanagwal, Jyoti,Kumar, Rajesh,Devi, Rekha,Bala, Manju,Sehrawat, Priyanka,Khatkar,Taxak
-
-
Read Online
- Small Molecule Inhibitor that Stabilizes the Autoinhibited Conformation of the Oncogenic Tyrosine Phosphatase SHP2
-
Genetic mutations in the phosphatase PTPN11 (SHP2) are associated with childhood leukemias. These mutations cause hyperactivation of SHP2 due to the disruption of the autoinhibitory conformation. By targeting the activation-associated protein conformational change, we have identified an SHP2 inhibitor (E)-1-(1-(5-(3-(2,4-dichlorophenyl)acryloyl)-2-ethoxy-4-hydroxybenzyl)-1,2,5,6-tetrahydropyridin-3-yl)-1H-benzo[d]imidazol-2(3H)-one (LY6, 1) using computer-aided drug design database screening combined with cell-based assays. This compound inhibited SHP2 with an IC50 value of 9.8 μM, 7-fold more selective for SHP2 than the highly related SHP1. Fluorescence titration, thermal shift, and microscale thermophoresis quantitative binding assays confirmed its direct binding to SHP2. This compound was further verified to effectively inhibit SHP2-mediated cell signaling and proliferation. Furthermore, mouse and patient leukemia cells with PTPN11 activating mutations were more sensitive to this inhibitor than wild-type cells. This small molecule SHP2 inhibitor has a potential to serve as a lead compound for further optimization studies to develop novel anti-SHP2 therapeutic agents.
- Wu, Xiaoqin,Xu, Gang,Li, Xiaobo,Xu, Weiren,Li, Qianjin,Liu, Wei,Kirby, Karen A.,Loh, Mignon L.,Li, Jun,Sarafianos, Stefan G.,Qu, Cheng-Kui
-
-
Read Online
- Designing of luminescent complexes of europium(III) ion with hydroxyl ketone and nitrogen donor secondary ligands for improving the luminescence performance and biological actions
-
Europium based five luminescent europium(III) complexes with 2-hydroxy-4-ethoxyacetophenone (main ligand) and second chromophores, bathophenanthroline, 5,6-dimethyl-1,10-phenanthroline, 1,10-phenanthroline and 2,2-bipyridyl have been prepared by employing cost-effective solution precipitation method. The various advanced techniques are employed to investigate the structural information. Thermal study proclaims the thermal stability of complexes up to 155 °C. The analyzed band-gap for complexes opens the application of these complexes in laser system. The photoluminescent properties of complexes under ultraviolet light clearly reveal the presence of prominent emission peak (5D0→7F2 transition) centered at 611 nm responsible for intense red emission of complexes, which highlights the applicability of these complexes in advanced optoelectronic devices. Judd-Ofelt intensity parameters, internal quantum efficiency and sensitization mechanism confirm the luminescence efficiency of complexes. The complexes display the excellent antimicrobial and antioxidant features.
- Hooda, Pooja,Khanagwal, Jyoti,Khatkar, S. P.,Kumar, Rajesh,Poonam,Taxak, V. B.
-
-
Read Online
- Design, synthesis and QSAR study of 2′-hydroxy-4′-alkoxy chalcone derivatives that exert cytotoxic activity by the mitochondrial apoptotic pathway
-
Eleven 4′-alkoxy chalcones were synthesized and biologically evaluated for their antiproliferative activity against four human tumor cell lines (PC-3, MCF-7, HF-6, and CaSki). Compounds 3a-3d and 3f were selective against PC-3, with IC50 values ranging from 8.08 to 13.75 μM. In addition, chalcones 3a-3c did not affect the normal fibroblasts BJ cells. The most active and selective compounds were further evaluated for their effect on the progression of cell cycle in PC-3 cells, and chalcones 3a and 3c induced a G2/M phase arrest. Furthermore, it was found that these three chalcones induced the mitochondrial apoptotic pathway by regulating Bax and Bcl-2 transcripts and by increasing caspase 3/7 activation. Otherwise, the QSAR model indicates that the double bond of the α,β-unsaturated carbonyl, as well as the planar structure geometry, are important to the biological activity of the synthetized chalcones. Based on these studies, it was concluded that withdrawing substituents in ring A, decrease the antiproliferative activity. This is related to the possible mechanism of action of these compounds, where a Michael addition needs to take place in order to be a potent anticancer agent.
- Marquina, Silvia,Maldonado-Santiago, Maritza,Sánchez-Carranza, Jessica Nayelli,Antúnez-Mojica, Mayra,González-Maya, Leticia,Razo-Hernández, Rodrigo Said,Alvarez, Laura
-
-
- Natural product Hirtellanine B and its derivatives in the preparation process for the preparation of medicine for treating tumor with the application of the
-
The present invention provides a preparation method of a natural product Hirtellanine B, wherein 2,4,6-trihydroxyacetophenone is adopted as a raw material, and steps of compound a preparation, compound b preparation, compound c preparation, compound d preparation, compound e preparation, compound f preparation, compound g preparation, and the like are performed to prepare the natural product Hirtellanine B. According to the present invention, biological activity screening is performed on Hirtellanine B and 14 Hirtellanine B derivatives, and results show that the natural product Hirtellanine B can inhibit proliferations of Jurkat cells, Raji cells and K562 cells, and the compounds provide a certain inhibition activity for tumor cells. The method has characteristics of easily available raw material, high reaction yield and reasonable operation, and is suitable for industrial production. The Hirtellanine B and the derivatives thereof can be used for preparing tumor treatment drugs, and have great clinical values. The natural product Hirtellanine B preparation method reaction formulas are as the follows.
- -
-
Paragraph 0065; 0150
(2016/10/10)
-
- Design, synthesis, and biological evaluation of Mannich bases of heterocyclic chalcone analogs as cytotoxic agents
-
The chalcone skeleton (1,3-diphenyl-2-propen-1-one) is a unique template that is associated with various biological activities. We synthesized Mannich bases of heterocyclic chalcones (9-47) using a one-step Claisen-Schmidt condensation of heterocyclic aldehydes with Mannich bases of acetophenones, and tested the target compounds for cytotoxicity against three human cancer cell lines (prostate, PC-3; breast, MCF-7; nasopharynx, KB) and a multi-drug resistant subline (KB-VIN). Out of the 39 chalcones synthesized, 31 compounds showed potent activity against at least one cell line with IC50 values ranging from 0.03 to 3.80 μg/mL. Structure-activity relationships (SAR) are also discussed.
- Reddy, M. Vijaya Bhaskar,Su, Chung-Ren,Chiou, Wen-Fei,Liu, Yi-Nan,Chen, Rosemary Yin-Hwa,Bastow, Kenneth F.,Lee, Kuo-Hsiung,Wu, Tian-Shung
-
p. 7358 - 7370
(2008/12/22)
-
- INHIBITORS OF HEPATITIS C VIRUS RNA-DEPENDENT RNA POLYMERASE, AND COMPOSITIONS AND TREATMENTS USING THE SAME
-
The present invention provides compounds of formula (4), and their pharmaceutically acceptable salts and solvates, which are useful as inhibitors of the Hepatitis C virus (HCV) polymerase enzyme and are also useful for the treatment of HCV infections in HCV-infected mammals. The present invention also provides pharmaceutical compositions comprising compounds of formula (4), their pharmaceutically acceptable salts and solvates. Furthermore, the present invention provides intermediate compounds and methods useful in the preparation of compounds of formula (4).
- -
-
Page/Page column 125
(2008/06/13)
-
- SYNTHESIS AND MESOMORPHIC PROPERTIES OF THREE HOMOLOGOUS SERIES OF 4,4 prime -DIALKOXY- alpha , alpha prime -DIMETHYLBENZALAZINES.
-
Three homologous series of alpha , alpha prime -dimethylbenzalazines have been synthesized: 4,4 prime -dialkoxy- alpha , alpha prime -dimethylbenzalazines, 4,4 prime -dialkoxy-2,2 prime -dihydroxy- alpha , alpha prime -dimethylbenzalazines, and 4,4 prime -dialkoxy-2-hydroxy- alpha , alpha prime -dimethylbenzalazines. The influence of molecular structure on the mesomorphic properties was studied. Mesomorphic properties and phase transitions were determined using a polarizing hot-stage microscope and a differential scanning calorimeter. The introduction of one or two hydroxyl groups in position 2- or 2-and 2 prime -of the aromatic rings (4,4 prime -dialkoxy-2-hydroxy- alpha , alpha prime -dimethylbenzalazines and 4,4 prime -dialkoxy-2,2 prime -dihydroxy- alpha , alpha prime -dimethylbenzalazines respectively) gives molecules with an excellent mesogenic quality, and all the prepared compounds of these series exhibit mesomorphism. Compounds of the series with two hydroxyl groups exhibit smectic polymorphism which is not so in the case of the compounds of the other series. The melting temperatures are systematically lower for the 4,4 prime -dialkoxy-2-hydroxy- alpha , alpha prime -dimethylbenzalazines than for the other two series.
- Marcos,Melendez,Serrano
-
p. 157 - 172
(2007/10/02)
-
