A concise synthesis of -bicyclo[6.1.0]nonyne carboxylic acid.

Bicyclo[6.1.0]nonyne carboxylic acid (BCN-COOH) is a valuable intermediate for the development of bioorthogonal click reagents.

A Dual-Purpose Non-Canonical Amino Acid for the Expanded Genetic Code: Combining Metal-Binding and Click Chemistry.

A rationally designed dual-purpose non-canonical amino acid (Trz) has been synthesised and successfully incorporated into a protein scaffold by genetic code expansion. Trz contains a 5-pyridyl-1,2,4-triazine system, which allows for inverse-electron-demand Diels-Alder (IEDDA) reactions to occur on the triazine ring and for metal ions to be chelated both before and after the click reaction. Trz was successfully incorporated into a protein scaffold and the IEDDA utility of Trz demonstrated through the site-specific labelling of the purified protein with a bicyclononyne.

Annealing 1,2,4-triazine to iridium(III) complexes induces luminogenic behaviour in bioorthogonal reactions with strained alkynes.

A phenanthroline-type ligand containing an annealed 1,2,4-triazine ring was used to prepare novel Ir(III) complexes 3 and 4. The complexes are non-luminescent but show luminogenic behaviour following the inverse electron demand Diels-Alder (IEDDA) reaction with bicyclononyne (BCN) derivatives. It was observed that the complexes react with BCN-C10 faster than the corresponding free ligands.

Increasing circulation of multi-drug resistant tuberculosis strains in Buryatia, high-burden and ethnically diverse region in the Russian Far East.

Buryatia is a multidrug-resistant tuberculosis (MDR-TB) high-burden region in the Russian Far East with ethnically diverse population (30 % Mongoloid Buryats and 65 % Russians). Two hundred M. tuberculosis strains from newly-diagnosed patients were subjected to phenotypic testing and genotyping.

Trinuclear Cyclometalated Iridium(III) Complex Exhibiting Intense Phosphorescence of an Unprecedented Rate.

Herein, we present two novel cyclometalated Ir(III) complexes of dinuclear and trinuclear design, and , respectively, where is 4,6-di(4-tert-butylphenyl)pyrimidine ligand and is acetylacetonate ligand. In both cases, -diastereomers were isolated during the synthesis. The materials show intense phosphorescence of outstanding rates ( = Φ/τ) with corresponding radiative decay times of only τ = 1/ = 0.

Thermally activated delayed fluorescence in a deep red dinuclear iridium(iii) complex: a hidden mechanism for short luminescence lifetimes.

The high luminescence efficiency of cyclometallated iridium(iii) complexes, including those widely used in OLEDs, is typically attributed solely to the formally spin-forbidden phosphorescence process being facilitated by spin-orbit coupling with the Ir(iii) centre. In this work, we provide unequivocal evidence that an additional mechanism can also participate, namely a thermally activated delayed fluorescence (TADF) pathway. TADF is well-established in other materials, including in purely organic compounds, but has never been observed in iridium complexes.

Effect of cyclic substituents on the anti-cancer activity and DNA interaction of ruthenium(II) bis-phenanthroline dipyridoquinoline.

Ruthenium(II) complexes have emerged recently as candidates for anti-cancer therapy, where activity is related to lipohilicity, cellular localization, and specific interactions with biomolecules. In this work, two novel complexes were synthesized and are reported based on the [Ru(phen)(dipyrido[3,2-:2',3'-]quinoxaline] framework. Compared to the parent complex, annealing of cyclopenteno and cyclohexeno rings to the extended ligand substantially increased cytotoxicity towards a number of cancer cell lines, and induced apoptosis.

Unusual Excimer/Dimer Behavior of a Highly Soluble C,N Platinum(II) Complex with a Spiro-Fluorene Motif.

In this work, we introduce a spiro-fluorene unit into a phenylpyridine (CN)-type ligand as a simple way to deplanarize the structure and increase the solubility of the final platinum(II)···complex. Using a spiro-fluorene unit, orthogonal to the main coordination plane of the complex, reduces intermolecular interactions, leading to increased solubility but without significantly affecting the ability of the complex to form Pt···Pt dimers and excimers. This approach is highly important in the design of platinum(II) complexes, which often suffer from low solubility due to their mainly planar structure, and offers an alternative to the use of bulky alkyl groups.

Catching up with tetrazines: coordination of Re(I) to 1,2,4-triazine facilitates an inverse electron demand Diels-Alder reaction with strained alkynes to a greater extent than in corresponding 1,2,4,5-tetrazines.

Inverse electron demand Diels Alder (IEDDA) reactions of 1,2,4-triazines are of interest to biorthogonal chemistry but suffer from slow kinetics. It is shown here that coordination of Re(I) to a 1,2,4-triazine ring speeds up the IEDDA reaction with bicyclooctyne (BCN) by a factor of 55. Comparative analysis with corresponding 1,2,4,5-tetrazine analogues reveals that the origin of the increased reactivity is markedly different and more profound than in tetrazine analogues.

Electroluminescence of Tetradentate Pt(II) Complexes: O^N^N^O versus C^N^N^O Coordination.

Alkylation of one of the phenolic hydroxyl groups in a salen-type tetradentate ligand changes the coordination mode from O^N^N^O to the cyclometallating C^N^N^O type. The ligand was used to synthesize a new cyclometalated luminescent Pt(II) complex . While in solution the complex is poorly luminescent, in the solid state the emission is reinstated, which allowed one to evaluate complex as a phosphorescent emitter in organic light-emitting diodes.

Aligning π-Extended π-Deficient Ligands to Afford Submicrosecond Phosphorescence Radiative Decay Time of Mononuclear Ir(III) Complexes.

Herein, we report a profound investigation of the photophysical properties of three mononuclear Ir(III) complexes (Hdppm-4,6-bis(4-(-butyl)phenyl)pyrimidine), (-acetylacetonate), and (Hppy-phenylpyridine). The heteroleptic is found to emit with efficiency above 80% and feature a remarkably high rate of emission. As measured under ambient temperature, emits with the unusually short (sub-μs) radiative decay time of τ = τ/Φ = 1/ = 0.

[Airway stenting in patients with complex benign tracheobronchial stenosis].

Tracheal and bronchial stenting is actively used for cancer and benign airway stenosis. This procedure is common in patients with advanced cancer. Stenting ensures breathing and availability of early chemo- and radiotherapy without the need for tracheostomy.

Memristor Degradation Analysis Using Auxiliary Volt-Ampere Characteristics.

The memristor is one of the modern microelectronics key devices. Due to the nanometer scale and complex processes physic, the development of memristor state study approaches faces limitations of classical methods to observe the processes. We propose a new approach to investigate the degradation of six Ni/SiN/p+Si-based memristors up to their failure.

Research and Development of Parameter Extraction Approaches for Memristor Models.

Memristors are among the most promising devices for building neural processors and non-volatile memory. One circuit design stage involves modeling, which includes the option of memristor models. The most common approach is the use of compact models, the accuracy of which is often determined by the accuracy of their parameter extraction from experiment results.

A Study of the Applicability of Existing Compact Models to the Simulation of Memristive Structures Characteristics on Low-Dimensional Materials.

The use of low-dimensional materials is a promising approach to improve the key characteristics of memristors. The development process includes modeling, but the question of the most common compact model applicability to the modeling of device characteristics with the inclusion of low-dimensional materials remains open. In this paper, a comparative analysis of linear and nonlinear drift as well as threshold models was conducted.

Exceptionally fast radiative decay of a dinuclear platinum complex through thermally activated delayed fluorescence.

A novel dinuclear platinum(ii) complex featuring a ditopic, bis-tetradentate ligand has been prepared. The ligand offers each metal ion a planar ^^^ coordination environment, with the two metal ions bound to the nitrogen atoms of a bridging pyrimidine unit. The complex is brightly luminescent in the red region of the spectrum with a photoluminescence quantum yield of 83% in deoxygenated methylcyclohexane solution at ambient temperature, and shows a remarkably short excited state lifetime of 2.

Non-Stereogenic Dinuclear Ir(III) Complex with a Molecular Rack Design to Afford Efficient Thermally Enhanced Red Emission.

Cyclometalated complexes containing two or more metal centers were recently shown to offer photophysical properties that are advantageous compared to their mononuclear analogues. Here we report the design, synthesis, and luminescent properties of a dinuclear Ir(III) complex formed by a ditopic NCN-NCN bridging ligand (L) with pyrimidine as a linking heterocycle. Two dianionic CNC terminal ligands were employed to achieve a charge-neutral and nonstereogenic dinuclear complex .

The formation and migration of non-equivalent oxygen vacancies in PrBaCoMO, where M = Fe, Co, Ni and Cu.

The ab initio calculated defect formation energies are used for assessment of high-temperature thermodynamic functions that govern the appearance of oxygen vacancies in PrBaCo2-xMxO6-δ, where M = Fe, Co, Ni and Cu. The free energy of oxygen vacancy formation is shown to depend on the dopant and total oxygen content in the cobaltite. The experimentally observed trend for the oxygen vacancy concentration to increase with the atomic number of 3d dopants from Fe to Cu is explained as a result of the decrease of bond strength.

Halide-Enhanced Spin-Orbit Coupling and the Phosphorescence Rate in Ir(III) Complexes.

The spin-forbidden nature of phosphorescence in Ir(III) complexes is relaxed by the metal-induced effect of spin-orbit coupling (SOC). A further increase of the phosphorescence rate could potentially be achieved by introducing additional centers capable of further enhancing the SOC effect, such as metal-coordinated halides. Herein, we present a dinuclear Ir(III) complex that contains two Ir(III)-iodide moieties.

Near Infrared Phosphorescent Dinuclear Ir(III) Complex Exhibiting Unusually Slow Intersystem Crossing and Dual Emissive Behavior.

A dinuclear iridium(III) complex shows dual emission consisting of near infrared (NIR) phosphorescence (λ = 714 nm, CHCl, = 300 K) and green fluorescence (λ = 537 nm). The NIR emission stems from a triplet state (T) localized on the ditopic bridging ligand (LC). Because of the dinuclear molecular structure, the phosphorescence efficiency (Φ = 3.

A flexible topo-optical sensing technology with ultra-high contrast.

Elastic folding, a phenomenon widely existing in nature, has attracted great interests to understand the math and physical science behind the topological transition on surface, thus can be used to create frontier engineering solutions. Here, we propose a topo-optical sensing strategy with ultra-high contrast by programming surface folds on targeted area with a thin optical indicator layer. A robust and precise signal generation can be achieved under mechanical compressive strains (>0.

Unusual dual-emissive heteroleptic iridium complexes incorporating TADF cyclometalating ligands.

Five new neutral heteroleptic iridium(iii) complexes IrL(pic) (2-6) based on the archetypical blue emitter FIrpic have been synthesised. The cyclometallating ligands L are derived from 2-(2,6-F-3-pyridyl)-4-mesitylpyridine (7), 2-(3-cyano-2,6-F-phenyl)-4-mesitylpyridine (8), 2-(2,6-F-phenyl)-4-[2,7-(HexO)-9H-carbazol-9-yl]pyridine (9), 2-(2,6-F-3-pyridyl)-4-[2,7-(HexO)-9H-carbazol-9-yl]pyridine (10) and 2-(3-cyano-2,6-F-phenyl)-4-[2,7-(HexO)-9H-carbazol-9-yl]pyridine (11) for complexes 2, 3, 4, 5 and 6, respectively. The carbazole-functionalised ligands 9-11 show weak thermally activated delayed fluorescence (TADF) in solution.

Iridium(iii) complexes of 1,2,4-triazines as potential bioorthogonal reagents: metal coordination facilitates luminogenic reaction with strained cyclooctynes.

In this paper we describe unprecedented Ir(iii) complexes of 5-(2-pyridyl)-1,2,4-triazine and their reactivity towards the strained cyclooctyne BCN. The coordination of a 1,2,4-triazine ring to an iridium(iii) ion drastically increases the speed of the reaction, showing the second order rate constant of 8 M-1 s-1, the record value to date for a triazine-BCN reaction.

Unusually Fast Phosphorescence from Ir(III) Complexes via Dinuclear Molecular Design.

The design and detailed photophysical study of two novel Ir(III) complexes featuring mono- and dinuclear design are presented. Emission quantum yield and decay times in solution are Φ = 90% and τ(300 K) = 1.16 μs for the mononuclear complex , and Φ = 95% and τ(300 K) = 0.

Exploring the Subtle Effect of Aliphatic Ring Size on Minor Actinide-Extraction Properties and Metal Ion Speciation in Bis-1,2,4-Triazine Ligands.

The synthesis and evaluation of three novel bis-1,2,4-triazine ligands containing five-membered aliphatic rings are reported. Compared to the more hydrophobic ligands 1-3 containing six-membered aliphatic rings, the distribution ratios for relevant f-block metal ions were approximately one order of magnitude lower in each case. Ligand 10 showed an efficient, selective and rapid separation of Am and Cm from nitric acid.