Two kinds of silver(I) coordination polymers consisting of the same chemical composition, [Ag(CFSO)(L)] [L is 2-methylidene-1,3-bis(nicotinoyloxy)propane], were synthesized and characterized by infrared (IR) and photoluminescence (PL) spectroscopy, elemental and thermal analyses, and single-crystal X-ray diffractometry; these are catena-poly[[(trifluoromethanesulfonato-κO)silver(I)]-μ-2-methylenepropane-1,3-diyl dinicotinate-κN:N'], [Ag(CFSO)(CHNO)], and its chloroform monosolvate, {[Ag(CFSO)(CHNO)]·CHCl}. The X-ray crystallographic measurements revealed that the silver(I) compounds exhibit one-dimensional sinusoidal or helical molecular structures depending on the solvent used for crystallization. Self-assembly in a methanol/chloroform mixture produces the sinusoidal molecular strand, whereas recrystallization from acetonitrile medium affords a racemic mixture of the helical strands.
View Article and Find Full Text PDFMany stress conditions including chemotherapy treatment is known to activate Src and under certain condition Src can induce the apoptotic signal via c-Jun N-terminal kinase (JNK) activation. Here we report that the newly synthesized β-phenylacrylic acid derivatives, MHY791 and MHY1036 (MHYs), bind to epidermal growth factor receptor (EGFR) tyrosine kinase domains and function as EGFR inhibitors, having anti-cancer activities selectively in wild-type KRAS colon cancer. Mechanistically, MHYs-induced Src/JNK activation which enhanced their pro-apoptotic effects and therefore inhibition of Src by the chemical inhibitor PP2 or Src siRNA abolished the response.
View Article and Find Full Text PDFBioorg Med Chem Lett
November 2017
Viriditoxin is a fungal secondary metabolite of the fungus Paecilomyces variotii derived from the inner tissues of the giant jellyfish Nemopilema nomurai. Viriditoxin exhibits antibacterial activity against Streptococcus iniae and Streptococcus parauberis, which are major pathogens of aqua cultured fish. Viriditoxin induced abnormal cell morphologies in the fish pathogens S.
View Article and Find Full Text PDF(bacterial grain rot), pv. (bacterial leaf blight), and subsp. (bacterial brown stripe) are major seedborne pathogens of rice.
View Article and Find Full Text PDFThe palladium(ii) cyclophane systems, constructed by previously reported proof-of-concept self-assembly, represent a crucial landmark in the field of effective and recyclable scavenging of triiodide (I) in the photo-cyclopropanation of alkenes with CHI. The scavenger's driving force behind photo-cyclopropanation is the efficient in situ crystallization of triiodide-exchanged species. The exact quantitative photoreaction yields according to the mole ratios of the cyclophane system are impressive.
View Article and Find Full Text PDFBioorg Med Chem Lett
October 2016
Hamacanthins are a class of antibacterial bisindole alkaloids isolated from marine sponges. Based on structure-activity relationships and in silico MRSA PK binding analysis of these bisindole alkaloids, the authors designed new hamacanthin B derivatives and evaluated their antibacterial activities against drug-resistant pathogens. Racemates of the synthetic products were resolved into their enantiomers by chiral separation using a cellulose column, and antibacterial activities were compared.
View Article and Find Full Text PDFAcc Chem Res
September 2016
Tailor-made molecular channel architectures are a hot issue in the fields of nanotechnology, molecular sieves, ion sensors, recognition, confined space reactors, and fluidic transport systems. Carbon nanotubes have been a particular focus, though they cannot easily be synthesized to predefined structures and sizes. Rational design and construction of molecular channel structures based on coordination chemistry has been recognized as a useful approach.
View Article and Find Full Text PDFPaecilocin A, a phthalide derivative isolated from the jellyfish-derived fungus Paecilomyces variotii, activates PPAR-γ (Peroxisome proliferator-activated receptor gamma) in rat liver Ac2F cells. Based on a SAR (Structure-activity relationships) study and in silico analysis of paecilocin A-mimetic derivatives, additional N-substituted phthalimide derivatives were synthesized and evaluated for PPAR-γ agonistic activity in both murine liver Ac2F cells and in human liver HepG2 cells by luciferase assay, and for adipogenic activity in 3T3-L1 cells. Docking simulation indicated PD6 was likely to bind most strongly to the ligand binding domain of PPAR-γ by establishing crucial H-bonds with key amino acid residues.
View Article and Find Full Text PDFWe fine mapped the Xa4 locus and developed a pyramided rice line containing Xa3 and Xa4 R - alleles and a cold-tolerance QTL. This line will be valuable in rice breeding. Bacterial blight (BB) caused by Xanthomonas oryzae pv.
View Article and Find Full Text PDFA series of Pd6L4-type neutral coordination cages, [Pd6X12L4] (X(-) = Cl(-) and Br(-)), are constructed via self-assembly of (COD)PdCl2 and K2PdBr4 with C3-symmetric N,N',N''-tris(2-pyridinylmethyl)-1,3,5-benzenetricarboxamide (L), respectively. The iodide analogue [Pd6I12L4] is smoothly synthesized from [Pd6Br12L4] in the presence of CH2I2 under mild conditions. The replacement of bromide to iodide in the nanocage system represents a landmark achievement in synthetic-methodology development.
View Article and Find Full Text PDFJ Adv Prosthodont
February 2016
Purpose: This study was conducted to evaluate the effects of full-coverage all-ceramic zirconia, lithium disilicate glass-ceramic, leucite glass-ceramic, or stainless steel crowns on antagonistic primary tooth wear.
Materials And Methods: There were four study groups: the stainless steel (Steel) group, the leucite glass-ceramic (Leucite) group, the lithium disilicate glass-ceramic (Lithium) group, and the monolithic zirconia (Zirconia) group. Ten flat crown specimens were prepared per group; opposing teeth were prepared using primary canines.
Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight (BB) in rice (Oryza sativa L.).
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2016
A synthetic strategy for the generation of new molecular species utilizing a provision of nature is presented. Nano-dimensional (23(2)×21(1)×16(1) ų) hetero-four-layered trimetallacyclophanes were constructed by proof-of-concept experiments that utilize a suitable combination of π⋅⋅⋅π interactions between the central aromatic rings, tailor-made short/long spacer tridentate donors, and the combined helicity. The behavior of the unprecedented four-layered metallacyclophane system offers a landmark in the development of new molecular systems.
View Article and Find Full Text PDFHerein, we report the advanced-concept triple-functionality of a metal-organic nanotube (MONT), which acts as a reservoir for unstable reactants, a photoreaction platform, and a scavenger for byproduct iodine. Self-assembly of CdI2 with a new Y-type ligand (L) produces the substantial 1D MOF, [CdI2(L)], thus forming a thick nanotube with a 1.4 nm diameter.
View Article and Find Full Text PDFThe self-assembly of Zn(II) ions with 1,3,5-tris(isonicotinoyloxyethyl)cyanurate produces new topological (4(2)⋅12(4))3(4(3))4 2D metal-organic frameworks (MOFs) with anion-confining cages. The eclipsed assembly of each 2D MOF by π-π stacking of cyanurate moieties (3.352(5) Å) forms 3D MOFs consisting of nanochannels (10.
View Article and Find Full Text PDFA new bacterial blight resistance gene has been identified through fine-mapping, which confers high levels of resistance to all Korean Xanthomonas oryzae pv. oryzae (Xoo) races, including the new Xoo race K3a. Rice bacterial leaf blight (BB) disease caused by Xanthomonas oryzae pv.
View Article and Find Full Text PDFA series of 25 × 25 × 25 Å(3) octahedral coordination cages [Pd6(L)8](NO3)12 (L = L(1), 1; L = L(2), 2; L(1) = tris(6-quinolyl)trimesic ester; L(2) = N,N',N''-tris(6-quinolyl)-1,3,5-benzenetricarboxamide) is reported. L(1) and L(2) are indistinguishable for construction of octahedral nanocages, and thus the desirable mixed ligand nanocage comprising a statistical ligand distribution ([Pd6(L(1))n(L(2))8-n](NO3)12, 3) can be efficiently constructed. However, the nanocages are distinguishable for functions such as photoluminescence (PL) and catalysis.
View Article and Find Full Text PDFXanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight (BB) in rice. To study its function, a random insertion mutation library of Xoo was constructed using the Tn5 transposon.
View Article and Find Full Text PDFResearch on the construction, crystal morphology, and functions of a novel zeolite L-mimic metal-organic framework (ZLMOF) was carried out. Treatment of the tubular crystals with AgBF4 in acetone at 40 °C smoothly coated the surface of the ZLMOF crystals with silver(0) nanoparticles.
View Article and Find Full Text PDFWe describe the development of a polymerase chain reaction method for the rapid, precise, and specific detection of the Xanthomonas oryzae pv. oryzae (Xoo) K3a race, the bacterial blight pathogen of rice. The specific primer set was designed to amplify a genomic locus derived from an amplified fragment length polymorphism specific for the K3a race.
View Article and Find Full Text PDFSelf-assembly of ZnX2 (X = Cl, Br, and I) with N,N',N''-tris(2-pyridinylethyl)-1,3,5-benzenetricarboxamide (L) as a tridentate N-donor ligand yields discrete C3-symmetric trimetallic zinc(II) complexes, [Zn3X6L(MeOH)3]. These form, via π∙∙∙π interactions and NH∙∙∙∙O=C hydrogen-bonds, an ensemble constituting a unique columnar stacking structure in an abab staggered fashion. For this series of complexes, the halogen effects on the photoluminescence, catalysis, and thermal properties were investigated.
View Article and Find Full Text PDFBackground: The development of resistant cultivars has been the most effective and economical strategy to control bacterial leaf blight (BB) disease of rice caused by Xanthomonas oryzae pv. oryzae (Xoo). Molecular markers have made it possible to identify and pyramid valuable genes of agronomic importance in resistance rice breeding.
View Article and Find Full Text PDFSelf-assembly of CuX2 (X(-) = ClO4(-) and BF4(-)) with 2,3-bis(nicotinoyloxy)naphthalene yields a 1D loop-chain skeleton. The loop-chains form an ensemble constituting a unique 3D kagome-type structure with both hexagonal and trigonal supra-channels. The unprecedented supra-channel effects on the catalytic oxidation of 3,5-di-tert-butylcatechol to 3,5-di-tert-butylbenzoquinone were investigated.
View Article and Find Full Text PDF