2159-40-2Relevant articles and documents
The novel synthesis of tris-cyclometalated iridium(III) complexes for saturated red organic light-emitting diodes with low efficiency roll-off
Liu, Lei,Mei, Qun-bo,Tong, Bi-hai,Yang, Jiu-chang,Ye, Shang-hui
, (2021/04/12)
A series of homoleptic tris-cyclometalated iridium(III) complexes (Ir2–Ir4) have been synthesized by the direct functionalization of a template complex (Ir1) through a Suzuki cross-coupling reaction. We revealed the coordination arrangement of Ir4 by single X-ray structural analysis and the molecule showed a facial configuration. All the complexes showed red emission with emission maxima at 591–624 nm, short lifetimes of 1.38–2.19 μs and photoluminescence quantum yields in the range of 28–42%. Most importantly, the full width at half maximum (FWHM) of the emission maxima of these complexes was less than 48 nm. These complexes exhibited good thermal stability with Td of 368–400 °C. Density functional theory (DFT) calculations were used to study the electronic structure information of these iridium(III) complexes. Organic light emitting diodes (OLEDs) based on these complexes as dopant emissive materials were fabricated. Among them the device based on Ir1 has a maximum current efficiency and external quantum efficiency of 15.67 cd A?1 and 10.06%, respectively. The device with low efficiency and EQE roll-off that 97–99% efficiency and EQEmax maintained at 1000 cd m?2. Meanwhile, the CIE(x,y) coordinates of these extended complexes were (0.65, 0.33), (0.66, 0.33) and (0.68, 0.31), respectively. These data were very close to the standard red emission required by National Television System Committee (NTSC) (0.67, 0.33). These results suggest that these materials have potential application in OLEDs.
Discovery of Antibacterials That Inhibit Bacterial RNA Polymerase Interactions with Sigma Factors
Ye, Jiqing,Chu, Adrian Jun,Harper, Rachel,Chan, Shu Ting,Shek, Tsun Lam,Zhang, Yufeng,Ip, Margaret,Sambir, Mariya,Artsimovitch, Irina,Zuo, Zhong,Yang, Xiao,Ma, Cong
, p. 7695 - 7720 (2020/07/21)
Formation of a bacterial RNA polymerase (RNAP) holoenzyme by a catalytic core RNAP and a sigma (σ) initiation factor is essential for bacterial viability. As the primary binding site for the housekeeping σ factors, the RNAP clamp helix domain represents an attractive target for novel antimicrobial agent discovery. Previously, we designed a pharmacophore model based on the essential amino acids of the clamp helix, such as R278, R281, and I291 (Escherichia coli numbering), and identified hit compounds with antimicrobial activity that interfered with the core-σ interactions. In this work, we rationally designed and synthesized a class of triaryl derivatives of one hit compound and succeeded in drastically improving the antimicrobial activity against Streptococcus pneumoniae, with the minimum inhibitory concentration reduced from 256 to 1 μg/mL. Additional characterization of antimicrobial activity, inhibition of transcription, in vitro pharmacological properties, and cytotoxicity of the optimized compounds demonstrated their potential for further development.
A facile greener synthesis, antimicrobial evaluation and molecular modelling of new 4-aryl-2-(3-(2-(trifluoromethyl)phenyl)-1,8-naphthyridin-2-yl)phthalazin-1(2H)-one derivatives
Sakram, Boda,Ravi, Dharavath,Raghupathi, Mutyala,Kumar, Boda Sathish,Anantha Lakshmi
, p. 2007 - 2022 (2019/01/10)
Abstract: The synthesis of 4-aryl-2-(3-(2-(trifluoromethyl)phenyl)-1,8-naphthyridin-2-yl)phthalazin-1(2H)-ones was performed by cyclization of 2-hydrazinyl-3-(2-(trifluoromethyl)phenyl)-1,8-naphthyridine with 2-aroylbenzoic acids in ethanol containing a catalytic amount of concentrated sulfuric acid under solid state conditions. All these synthesized compounds (8a–h) were screened for their in vitro antibacterial activity against gram-positive bacteria such as (Staphylococcus aureus) and gram-negative bacteria (Escherichia coli) and also evaluated for their antifungal activity against Aspergillus Niger and Helmenthosphorium oryzae fungal strains. Some of the products demonstrate good antibacterial activity and moderate antifungal activity. In predominantly, 8b, 8d, 8g, and 8h compounds showed good to excellent antibacterial and antifungal activities. The antimicrobial activity of the compound 8 was further investigated with the help of in LibDock score docking study to predict the active sites. Graphical abstract: [Figure not available: see fulltext.].
