Synthesis, structure, and magnetic properties of [(S)-[PhCH(CH3)N(CH3)3]][Mn(CH3CN)2/3Cr(ox)3] x (CH3CN)_(solvate), a 2D chiral magnet containing a quaternary ammonium chiral cation

The synthesis, structure, and magnetic properties of a novel oxalate-based bimetallic magnet obtained by using the chiral (S)-trimethyl-(1-phenyl-ethyl)-ammonium, ((S)-[PhCH(CH3)N(CH3)3](+)), cation as template is reported. This compound can be formulated as [(S)-[PhCH(CH3)N(CH3)3]][Mn(CH3CN)2/3Cr(ox)3] x (CH3CN)_(solvate), and it crystallizes in the chiral trigonal space group P3. It shows a distorted two-dimensional honeycomb structure formed by Mn(II) and Cr(III) ions connected through oxalate anions with [(S)-[PhCH(CH3)N(CH3)3](+) cations and solvent molecules intercalated between the oxalate layers. Two-thirds of the Mn(II) ions of the honeycomb anionic network are heptacoordinated. This compound behaves as a soft ferromagnet with an ordering temperature of 5.6 K.     

Degenerations of 8-Dimensional 2-step Nilpotent Lie Algebras

Algebras and Representation Theory - In this work, we consider degenerations between 8-dimensional 2-step nilpotent Lie algebras over ? and obtain the geometric classification of the variety...     

Long-Term Monokaryotic Cultures of Pleurotus ostreatus var. florida Produce High and Stable Laccase Activity Capable to Degrade ß-Carotene

An extracellular laccase (Lacc10) was discovered in submerged cultures of Pleurotus ostreatus var. florida bleaching ß-carotene effectively without the addition of a mediator (650 mU/L, pH 4). Heterologous expression in P. pastoris confirmed the activity and structural analyses revealed a carotenoid-binding domain, which formed the substrate-binding pocket and is reported here for the first time. In order to increase activity, 106 basidiospore-derived monokaryons and crosses of compatible progenies were generated. These showed high intraspecific variability in growth rate and enzyme formation. Seventy-two homokaryons exhibited a higher activity-to-growth-rate-relation than the parental dikaryon, and one isolate produced a very high activity (1800 mU/L), while most of the dikaryotic hybrids showed lower activity. The analysis of the laccase gene of the monokaryons revealed two sequences differing in three amino acids, but the primary sequences gave no clue for the diversity of activity. The enzyme production in submerged cultures of monokaryons was stable over seven sub-cultivation cycles.

     

Composites of Anthraquinone Dyes@HKUST-1 with Tunable Microstructuring: Experimental and Theoretical Interaction Studies

The metal–organic framework (MOF) HKUST-1 was employed as an interaction matrix for fundamental loading studies of anthraquinone dyes. Chosen dyes were alizarin (A), alizarin S (AS), disperse blue 1 (B1), disperse blue 3 (B3), disperse blue 56 (B56) and purpurin (P). All materials were characterized by XRD, FTIR, TGA and SEM. Hence the interaction of dyes with the framework was characterized by theoretical–experimental differential analysis. One-pot loading strategy resulted in more efficient scavenging of dyes, and reached 100 % for B56 using 50 mg L⁻¹. SEM revealed important microstructural changes, the smaller crystals ranged 0.8–3 μm in size and almost all composite sizes were from this to higher values, reaching 70 μm, with varying shapes. Two composites were larger in size range (about 2500–1000 μm), and were shaped as rods, octahedrons and coffin lids. Indeed, the microstructure could be modulated depending on preparation conditions and type of loaded dye. For the higher loading series, N₂ adsorption and XPS experiments were carried on to further evidence dye–MOF interactions. Ab initio prediction of structural properties for A@HKUST-1 and P@HKUST-1 were obtained by means of solid-state CRYSTAL14 code at the PBE0 level of theory. Computed findings evidenced two O→Cu coordinative bonds, one from O-ketone and the other from O-phenolate moiety as main interactions towards CuNET centers.     

Bimodal Therapeutic Agents Against Glioblastoma,One of the Most Lethal Forms of Cancer

About 95 % of people diagnosed with glioblastoma die within five years. Glioblastoma is the most aggressive central nervous system tumour. It is necessary to make progress in the glioblastoma treatment so that advanced chemotherapy drugs or radiation therapy or, ideally, two-in-one hybrid systems should be implemented. Tyrosine kinase receptors–inhibitors and boron neutron capture therapy (BNCT), together, could provide a therapeutic strategy. In this work, sunitinib decorated-carborane hybrids were prepared and biologically evaluated identifying excellent antitumoral- and BNCT-agents. One of the selected hybrids was studied against glioma-cells and found to be 4 times more cytotoxic than sunitinib and 1.7 times more effective than ¹⁰B-boronophenylalanine fructose complex when the cells were irradiated with neutrons.     

A brief review of the computational modeling of CO2 electroreduction on Cu electrodes

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Nucleophilic addition to substituted 1H-4,5-dihydroimidazolium salts

1H-4,5-Dihydroimidazolium salts 1 react readily with nucleophilic reagents originating cyclic products which may be stable or become transformed into acyclic compounds maintaining the structural ethylenediamine unit. With methylmagnesium iodide compound 1e affords the expected imidazolidine, but in the case of substituted 1-aryl-3-methyl-2-phenyl salts 1b-d the N-aryl-N′-methylethylenediamines 3b-d and acetophenone ( 4 ) were isolated, the process representing the transfer of the C-2 unit to a nucleophilic carbon. With alkaline cyanides salts 1 react efficiently affording α,α-diaminonitriles 5 . In these compounds the cyano group may be readily substituted by nucleophiles (hydroxyl anion, species with nucleophilic carbon and reagents that act by hydride ion transfer), in a way similar to the salts but with better yields.     

Synthesis,structural and larvicidal studies of a series of triorganotin chrysanthemumates

A series of triorganotin chrysanthemumates (2,2‐dimethyl‐3‐(2‐methyl‐1‐propenyl)cyclopropanecarboxylates) (R₃SnO₂CC₉H₁₅) where R = methyl, ethyl, n‐butyl and phenyl was synthesized. The solid state structures were deduced using infrared (IR) and Mössbauer spectroscopies. The spectroscopic results indicated that all the compounds were found to be five‐coordinated in the solid state. Based on the NMR results, all the compounds are tetrahedral in solution. Larvicidal activities of the compounds were evaluated against the second instar stage of Aedes aegypti, Anopheles stephensi and Culex pipiens quinquefasciatus mosquitoes. The toxicity results indicated that these compounds of triorganotins were effective larvicides against all three species of larvae. Copyright © 2011 John Wiley & Sons, Ltd.     

An approach to predictive-reactive scheduling of parallel machines subject to disruptions

In this paper, a new predictive-reactive approach to a parallel machine scheduling problem in the presence of uncertain disruptions is presented. The approach developed is based on generating a predictive schedule that absorbs the effects of possible uncertain disruptions through adding idle times to the job processing times. The uncertain disruption considered is material shortage, described by the number of disruption occurrences and disruption repair period. These parameters are specified imprecisely and modelled using fuzzy sets. If the impact of a disruption is too high to be absorbed by the predictive schedule, a rescheduling action is carried out. This approach has been applied to solving a real-life scheduling problem of a pottery company.