10602-00-3Relevant articles and documents
Design, synthesis and biological evaluation of LpxC inhibitors with novel hydrophilic terminus
Ding, Shi,Wang, Wen-Ke,Cao, Qiao,Chu, Wen-Jing,Lan, Le-Fu,Hu, Wen-Hao,Yang, Yu-She
, p. 763 - 767 (2015)
Abstract In order to develop novel LpxC inhibitors with good activities and metabolic stability, two series of compounds with hydrophilic terminus have been synthesized and their in vitro antibacterial activities against Escherichial coli and Pseudomonas aeruginosa were evaluated. Especially, compounds 22b and c exhibited comparable antibacterial activities to CHIR-090 and better metabolic stability than CHIR-090 and LPC-011 in liver microsomes (rat and mouse), which indicated the terminal methylsulfone may be a preferred structure in the design of LpxC inhibitors and worthy of further investigations.
Thermal solid state polymerization of p-ethynylbenzoic acid
Njus, Jeffrey M.,Sandman, Daniel J.,Yang, Lin,Foxman, Bruce M.
, p. 7645 - 7652 (2005)
While p-ethynylbenzoic acid (EBA) has been suggested to be reactive in the solid state, the structure-reactivity relationships and the nature of the product(s) have remained unknown. Crystallized from toluene, EBA is a monoclinic crystal, space group P21/n, a = 3.8684(4), b = 6.2329(4), c = 30.190(3) A; β= 90.281(8)°; V = 727.90 A3. The crystal structure contains linear chains and short intermolecular contacts between acetylene moieties, which provide a structural basis for initiation of topochemical reactivity. Heating of EBA leads to an amorphous poly(phenylacetylene) (PPA) derivative. The absorption and emission spectral characteristics of the polymer are discussed. Analogous to PPA, a subsequent thermal process leads to a cyclic trimer. Differential scanning calorimetry of EBA exhibits at least four exothermic processes, and these are discussed in terms of the polymerization and subsequent processes that ultimately lead to the cyclotrimer.
Control of the helicity of poly(phenylacetylene)s: From the conformation of the pendant to the chirality of the backbone
Louzao, Iria,Seco, Jose M.,Quinoa, Emilio,Riguera, Ricardo
, p. 1430 - 1433 (2010)
(Figure Presented) Helix sense selection: Tuning the conformational equilibrium of the pendants of poly(phenylacetylene)s allows selection of the helicity of the polymer in a reversible way. Complexation with appropriate metal cations (e.g. Ba2+) or changing the polarity of the solvent permits the reversible selection of the desired helix sense. A full picture of the mechanism explaining this phenomenon is presented.
Synthesis and properties of substituted polyacetylenes containing pyrene moieties in the side group
Sugano, Shou,Kouzai, Hiroaki
, p. 27 - 32 (2016)
A novel phenylacetylene derivative containing a pyrene group was synthesized and polymerized with various Rh complex catalysts. The obtained polymers were soluble in common organic solvents such as chloroform and THF. The Mw and Mw/Mn were estimated as ca. 12000-18000 and 1.31.7 respectively, and the polymer yields were estimated as around 5772%. The characteristic absorptions of ≡ C-H (3200 cm-1) and C≡C (2100 cm-1) stretchings seen in the monomer spectra have completely disappeared in the polymer spectra from IR spectrum. 1HNMR analysis confirmed that the acetylene triple bonds transformed to polyene double bonds. These polymers were found to be thermally stable based on TGA data. The synthesized polymers exhibited blue fluorescence. The fluorescence quantum yield in solution was high at 0.37-0.41. Furthermore, the obtained polymer had a long fluorescence lifetime.
Water-soluble nano-fluorogens fabricated by self-assembly of bolaamphiphiles bearing AIE moieties: Towards application in cell imaging
Xia, Yijun,Dong, Lin,Jin, Yingzhi,Wang, Shuai,Yan, Li,Yin, Shouchun,Zhou, Shixin,Song, Bo
, p. 491 - 497 (2015)
Nano-fluorogens with a mono-molecule layered structure are fabricated by self-assembly of a new bolaamphiphile bearing a tetraphenylethene moiety. The nano-fluorogens show good water-solubility, biocompatibility, and strong emission with a quantum yield as high as 15%. The nano-fluorogens, as prepared, are successfully applied to label and map HeLa cells. The images obtained have high contrast and resolution, showing a promising potential for fluorescence detection in bio-related systems.
Two- and three-dimensional silver(I)-organic networks generated from mono- and dicarboxylphenylethynes
Zhao, Ying,Zhang, Peng,Li, Bao,Meng, Xianggao,Zhang, Tianle
, p. 9097 - 9105 (2011)
Three phenylethynes bearing methyl carboxylate (HL1), monocarboxylate (H2L2), and dicarboxylate (H2L3) groups were utilized as ligands to synthesize a new class of organometallic silver(I)-ethynide complexes as bifunctional building units to assemble silver(I)-organic networks. X-ray crystallographic studies revealed that in [Ag2(L1) 2?AgNO3]∞ (1) (L1= 4-C 2C6H4CO2CH3), one ethynide group interacts with three silver ions to form a complex unit. These units aggregate by sharing silver ions with the other three units to afford a silver column, which are further linked through argentophilic interaction to generate a two-demensional (2D) silver(I) network. In [Ag2(L2) ?3AgNO3?H2O]∞ (2) (L2 = 4-CO2C6H4C2), the ethynide group coordinates to four silver ions to form a building unit (Ag4C 2C6H4CO2), which interacts through silver(I)-carboxylate coordination bonds to generate a wave-like 2D network and is subsequently connected by nitrate anions as bridging ligands to afford a three-demensional (3D) network. In [Ag3(L3)?AgNO 3]∞ (3) (L3 = 3,5-(CO2)2C 6H3C2), the building unit (Ag4C 2C6H3(CO2)2) aggregates to form a dimer [Ag8(L3)2] through argentophilic interaction. The dimeric units interact through silver(I)-carboxylate coordination bonds to directly generate a 3D network. The obtained results showed that as a building unit, silver(I)-ethynide complexes bearing carboxylate groups exhibit diverse binding modes, and an increase in the number of carboxylate groups in the silver(I)-ethynide complex unit leads to higher level architectures. In the solid state, all of the complexes (1, 2, and 3) are photoluminescent at room temperature.
Ribosome Rescue Inhibitors Kill Actively Growing and Nonreplicating Persister Mycobacterium tuberculosis Cells
Alumasa, John N.,Manzanillo, Paolo S.,Peterson, Nicholas D.,Lundrigan, Tricia,Baughn, Anthony D.,Cox, Jeffery S.,Keiler, Kenneth C.
, p. 634 - 644 (2017)
The emergence of Mycobacterium tuberculosis (MTB) strains that are resistant to most or all available antibiotics has created a severe problem for treating tuberculosis and has spurred a quest for new antibiotic targets. Here, we demonstrate that trans-translation is essential for growth of MTB and is a viable target for development of antituberculosis drugs. We also show that an inhibitor of trans-translation, KKL-35, is bactericidal against MTB under both aerobic and anoxic conditions. Biochemical experiments show that this compound targets helix 89 of the 23S rRNA. In silico molecular docking predicts a binding pocket for KKL-35 adjacent to the peptidyl-transfer center in a region not targeted by conventional antibiotics. Computational solvent mapping suggests that this pocket is a druggable hot spot for small molecule binding. Collectively, our findings reveal a new target for antituberculosis drug development and provide critical insight on the mechanism of antibacterial action for KKL-35 and related 1,3,4-oxadiazole benzamides.
Chirality assignment of amines and amino alcohols based on circular dichroism induced by helix formation of a stereoregular poly((4- carboxyphenyl)acetylene) through acid-base complexation
Yashima, Eiji,Matsushima, Teruyuki,Okamoto, Yoshio
, p. 6345 - 6359 (1997)
An optically inactive polyacetylene, poly((4-carboxyphenyl)acetylene) (poly-l), exhibits an induced circular dichroism (ICD) in the UV-visible region upon complexation with chiral amines and amino alcohols in DMSO and in the film, the sign of which reflects the stereochemistry including bulkiness, type (primary, secondary, or tertiary), and absolute configuration of the amines. Therefore, the polyacetylene can be used as a novel probe for determining the chirality of amines. Most primary amines and amino alcohols of the same configuration gave the same sign for the induced Cotton effect; however, secondary and/or tertiary amines used in the present study tended to show Cotton effect signs opposite to those of the primary amines and amino alcohols of the same configuration. The magnitude of the ICD likely increases with an increase in the bulkiness of the chiral amines. The complexation dynamics during the formation of the helical structure of poly-1 with chiral amines were investigated on the basis of the spin-spin relaxation behavior and 1H NMR, CD, and optical rotatory dispersion (ORD) titrations. The complex formation of poly-1 with chiral amines such as 1-(l- naphthyl)ethylamine and 2-amino-l-propanol exhibits a positive nonlinear effect between the enantiomeric excess of the chiral amines and amino alcohols and the observed ellipticity of the Cotton effects. The excess enantiomer bound to poly-1 may induce an excess of a single-handed helix (rightor left-handed helix), which may result in a more intense ICD than that expected from the ee of the amine. Moreover, it was found that the coexistence of achiral amines such as l-aminoethanol also induced an excess of one helical sense of poly-1.
Polyacetylene derivatives in perovskite solar cells: From defect passivation to moisture endurance
Faheem, M. Bilal,Jiang, Jiexuan,Lang, Xianhua,Li, Yanbo,Rong, Shanshan,Zeng, Qiugui,Zhao, Hui
, p. 13220 - 13230 (2021)
The last decade has witnessed the exploration of exceptional optoelectronic and photovoltaic properties of perovskite solar cells (PSCs) at the laboratory scale. Unfortunately, their sensitivity to moisture causes bulk degradation, hindering the commercialization of PSC devices. Despite the numerous strategies that have been developed to date in this field, effective passivation against moisture remains highly challenging. Here, we report a novel approach based on the incorporation of polyacetylene derivatives into the perovskite active layer to yield perovskite films with larger grains, lower defect density, and excellent robustness with respect to moisture. Moreover, it is revealed that the reduced trap-state density of these films is most likely due to the efficient coordination between the carboxylate moieties in the polymer and the undercoordinated Pb2+ in the perovskite. Upon adopting the polymer-doped perovskite as an active layer in inverted planar heterojunction PSCs with all-inorganic charge extraction layers, the power conversion efficiency (PCE) is improved to 20.41%, which is the highest value reported to date for this type of PSC to the best of our knowledge. Most importantly, the optimized device retained 90% of its initial PCE after aging in ambient air for 60 days due to its dual mechanism of moisture resistance. This work highlights an approach for developing high-performance PSCs with improved moisture stability and paves the way for their potential commercialization. This journal is
Nesting complexation of C60 with large, rigid D2 symmetrical macrocycles
Caricato, Marco,Coluccini, Carmine,Dondi, Daniele,Vander Griend, Douglas A.,Pasini, Dario
, p. 3272 - 3280 (2010)
A series of four chiral D2 symmetrical macrocycles, in which two 3,3′-disubstituted Binol units are bridged by conjugated organic spacers of differing lengths and/or electronic properties, have been synthesized and characterized. The four different bridges consist of either ether or ester linkages in combination with either short biphenyl spacers or long diethynylphenyl spacers. NMR, CD spectroscopy, and molecular modeling help rationalize the shape of the cyclic scaffolds and even subtle modifications in the bridging units lead to drastic changes in conformation. The three macrocycles with longer bridging units and/or ester linkages form stable 1:1 complexes with C60 in toluene. The one with a short spacer and ether linkage does not. The binding constants have been determined with a high degree of accuracy via equilibrium-restricted factor analysis; with long spacers and ester linkages log Ka = 4.37(2); with short spacers and ester linkages log Ka = 3.498(4); with long spacers and ether linkages log Ka = 3.509(2). The Royal Society of Chemistry 2010.
