Positional effects of electron-donating and withdrawing groups on the photophysical properties of single benzene fluorophores.

We investigated how the positional arrangement of electron-donating (amino) and electron-withdrawing (ester) groups in single benzene-based fluorophores influences their emission properties. By synthesizing 26 regioisomeric fluorophores, we achieved wavelength modulation from 322 to 539 nm, revealing key correlations between functional group positioning and photophysical behavior.

Highly emissive 4-carbazole-appended salen-indium complex: the effect of strong donor-acceptor interaction.

Herein, we report our findings on 4-carbazole (CBZ)-appended salen-based indium complexes, CBZIn1 and CBZIn2, which feature diimine bridges exhibiting different electron-accepting properties. Notably, CBZIn2 exhibited a significantly higher photoluminescence quantum efficiency (PLQY, ) in toluene than CBZIn1, with a value over 15 times greater ( = 57.7% for CBZIn2; = 3.

Inhibition of topoisomerase I shapes antitumor immunity through the induction of monocyte-derived dendritic cells.

Understanding the rationale of combining immunotherapy and other anticancer treatment modalities is of great interest because of interpatient variability in single-agent immunotherapy. Here, we demonstrated that topoisomerase I inhibitors, a class of chemotherapeutic drugs, can alter the tumor immune landscape, corroborating their antitumor effects combined with immunotherapy. We observed that topotecan-conditioned TC-1 tumors were occupied by a vast number of monocytic cells that highly express CD11c, CD64, and costimulatory molecules responsible for the favorable changes in the tumor microenvironment.

Synthesis and Photophysical Properties of a Series of Dimeric Indium Quinolinates.

A novel class of quinolinol-based dimeric indium complexes (-) was synthesized and characterized using H and C(H) NMR spectroscopy and elemental analysis. Compounds - exhibited typical low-energy absorption bands assignable to quinolinol-centered π-π* charge transfer (CT) transition. The emission spectra of - exhibited slight bathochromic shifts with increasing solvent polarity (-xylene < tetrahydrofuran (THF) < dichloromethane (DCM)).

Enhanced Immunogenicity of Engineered HER2 Antigens Potentiates Antitumor Immune Responses.

For cancer vaccines, the selection of optimal tumor-associated antigens (TAAs) that can maximize the immunogenicity of the vaccine without causing unwanted adverse effects is challenging. In this study, we developed two engineered Human epidermal growth factor receptor 2 (HER2) antigens, K965 and K1117, and compared their immunogenicity to a previously reported truncated HER2 antigen, K684, within a B cell and monocyte-based vaccine (BVAC). We found that BVAC-K965 and BVAC-K1117 induced comparable antigen-specific antibody responses and antigen-specific T cell responses to BVAC-K684.

Response of (Chlorophyceae) to Salt Stress Considering Nutrient Enrichment and Intracellular Proline Accumulation.

Aquatic organisms are exposed to a wide range of salinity, which could critically affect their survival and growth. However, their survival and growth response to salinity stress remain unclear. This study evaluates the growth response and intracellular proline accumulation of green algae, , isolated from brackish water, against dissolved salts stress with N and P enrichment.

Ir-Catalyzed C-H Amidation Using Carbamoyl Azides for the Syntheses of Unsymmetrical Ureas.

An iridium-catalyzed C-H amidation for the syntheses of unsymmetrical urea was developed using carbamoyl azides (R(R')N-C(O)-N) as the nitrogen source. A combination of iridium and silver gave an active catalyst for C-N bond formation. A variety of urea derivatives were synthesized using carbamoyl azides with only dinitrogen byproducts.

Photophysical Properties of Spirobifluorene-Based -Carboranyl Compounds Altered by Structurally Rotating the Carborane Cages.

9,9'-Spirobifluorene-based -carboranyl compounds and were prepared and fully characterized by multinuclear nuclear magnetic resonance (NMR) spectroscopy and elemental analysis. The solid-state structure of was also determined by single-crystal X-ray diffractometry. The two carboranyl compounds display major absorption bands that are assigned to -* transitions involving their spirobifluorene groups, as well as weak intramolecular charge-transfer (ICT) transitions between the -carboranes and their spirobifluorene groups.

Spirobifluorene-Based o-Carboranyl Compounds: Insights into the Rotational Effect of Carborane Cages on Photoluminescence.

9,9'-Spirobifluorene-based closo-o-carboranyl (SFC1 and SFC2) compounds and their nido-derivatives (nido-SFC1 and nido-SFC2) were prepared and characterized. The two closo-compounds displayed major absorption bands assignable to π-π* transitions involving the spirobifluorene group, as well as weak intramolecular charge-transfer (ICT) transitions between the o-carboranes and their spirobifluorene moieties. The nido-compounds exhibited slightly blueshifted absorption bands resulting from the absence of the ICT transitions corresponding to the o-carborane moieties due to the anionic character of the nido-o-carboranes.

Synthesis of o-carborane-functionalized metal-organic frameworks through ligand exchanges for aggregation-induced emission in the solid state.

The carborane (CB)-functionalized ligand was installed in a variety of MOFs through postsynthetic ligand exchange processes. This methodology is a general method for preparing o-CB-functionalized MOFs with known frameworks. Furthermore, the photoluminescence (PL) spectra revealed intriguing aggregation-induced emission (AIE) features following the systematic incorporation of o-CB functionalities into framework-type materials.

Carbazole-Appended Salen-Indium Conjugate Systems: Synthesis and Enhanced Luminescence Efficiency.

Novel carbazole-conjugated salen-In complexes ( and ) were prepared and fully characterized by H and C NMR spectroscopy, elemental analysis, and high-resolution mass spectrometry. The major low-energy absorption bands at λ = 342 nm for and 391 nm for , respectively, are assigned to typical intramolecular charge transfer (ICT) transitions between the carbazole unit and the salen-In center. The solvatochromism effects in various organic solvents and their large Stokes shift distinctly supported the ICT nature.

Effect of the Metal within Regioisomeric Paddle-Wheel-Type Metal-Organic Frameworks.

The effect of metal on the degree of flexibility upon evacuation of metal-organic frameworks (MOFs) has been revealed with positional control of the organic functionalities. Although Co-, Cu-, and Zn-based DMOFs (DMOF = DABCO MOF, DABCO = 1,4-diazabicyclo[2.2.

Efficient Aluminum Catalysts for the Chemical Conversion of CO into Cyclic Carbonates at Room Temperature and Atmospheric CO Pressure.

A series of dimeric aluminum compounds [Al(OCMe CH N(R)CH X)] [X=pyridin-2-yl, R=H (Pyr ); X= pyridin-2-yl, R=Me (Pyr ); X=furan-2-yl, R=H (Fur ); X= furan-2-yl, R=Me (Fur ); X=thiophen-2-yl, R=H (Thio ); X= thiophen-2-yl, R=Me (Thio )] containing heterocyclic pendant group attached to the nitrogen catalyze the coupling of CO with epoxides under ambient conditions. In a comparison of their catalytic activities with those of aluminum complexes without pendant groups at N [X=H, R=H (H ); X=H, R=Me (H )] or with non-heterocyclic pendant groups [X=CH CH OMe, R=H (OMe ); X=CH CH NMe , R=H (NMe2 ); X=CH CH NMe , R=Me (NMe2 )], complexes containing heterocycles, in conjunction with (nBu) NBr as a cocatalyst, show higher catalytic activities for the synthesis of cyclic carbonates under the same ambient conditions. The best catalyst system for this reaction is Pyr /(nBu) NBr system, which gives a turnover number of 99 and a turnover frequency of 4.

A Series of Quinolinol-Based Indium Luminophores: A Rational Design Approach for Manipulating Photophysical Properties.

An approach to the design of a series of quinolinol-based indium complexes that can exhibit different optical properties is proposed. Mono-incorporated (Inq and InMeq), bis-incorporated (InMeq), and tris-incorporated (Inq and InMeq) indium quinolinate complexes have been prepared. These complexes have also been characterized by X-ray crystallography.

Halide-Free and Bifunctional One-Component Catalysts for the Coupling of Carbon Dioxide and Epoxides.

In this paper, we first report a new class of halide-free and bifunctional one-component catalysts for the coupling of CO with epoxides. The catalysts do not need halide-based additives or tethered salts attached to the ligand when used for this coupling reaction. As the halide-free and bifunctional one-component catalysts, we chose nonionic and monomeric tetracarbonylchromium(0), tetracarbonylmolybdenum(0), and tetracarbonyltungsten(0) complexes chelated by modified ethylenediamines, namely N, N-dimethylethylenediamine, N, N'-dimethylethylenediamine, N, N, N'-trimethylethylenediamine, and N, N, N', N'-tetramethylethylenediamine.

Systematic Control of the Overlapping Energy Region for an Efficient Intramolecular Energy Transfer: Functionalized Salen-Al/Triphenylamine Guest-Host Assemblies.

A series of triphenylamine (TPA)-containing salen-Al assembly dyads, [salen(3- tBu-5-R)Al(OCH- p-N(CH))] [salen = N, N'-bis(salicylidene)ethylenediamine; R = H (D1), tBu (D2), Ph (D3), OMe (D4), and NMe (D5)], were prepared in good yield (50-80%) and fully characterized by NMR spectroscopy and elemental analysis. Both the UV/vis absorption and photoluminescence (PL) spectra of D1-D4, except for D5, in a tetrahydrofuran solution exhibited dual patterns, which are assignable to the salen-Al-centered π-π* transition (low-energy region) and the TPA-centered π-π* transition (high-energy region). In particular, the emission spectra of the dyads displayed interesting dual-emissive patterns via a significant intramolecular energy transfer (IET) process between the salen-Al moiety and TPA group.

2-Phenylpyridine- and 2-(benzo[b]thiophen-2-yl)pyridine-based o-carboranyl compounds: impact of the structural formation of aromatic rings on photophysical properties.

2-Phenylpyridine- and 2-(benzo[b]thiophen-2-yl)pyridine-based (ppy- and btp-based) o-carboranyl (Car1 and Car2) and their B(CH3)2-C∧N-chelated (Car1B and Car2B) compounds were prepared and fully characterised by multinuclear NMR spectroscopy and elemental analysis. The solid-state structure of Car2B was determined by single-crystal X-ray diffraction, which revealed a four-coordinated dimethylboryl centre. All compounds displayed major absorption bands that were assigned to π-π* transitions involving the ppy and btp moieties, as well as weak intramolecular charge-transfer (ICT) transitions between the o-carboranes and their aryl groups.

Effect of Planarity of Aromatic Rings Appended to o-Carborane on Photophysical Properties: A Series of o-Carboranyl Compounds Based on 2-Phenylpyridine- and 2-(Benzo[b]thiophen-2-yl)pyridine.

Herein, we investigated the effect of ring planarity by fully characterizing four pyridine-based -carboranyl compounds. -Carborane was introduced to the C4 position of the pyridine rings of 2-phenylpyridine and 2-(benzo[]thiophen-2-yl)pyridine ( and , respectively), and the compounds were subsequently borylated to obtain the corresponding -chelated compounds and . Single-crystal X-ray diffraction analysis of the molecular structures of and confirmed that -carborane is appended to the aryl moiety.

A salen-Al/carbazole dyad-based guest-host assembly: enhancement of luminescence efficiency via intramolecular energy transfer.

A novel class of salen-Al/carbazole dyads (D1 and D2) was synthesized and fully identified. The emission spectra of the dyads presented intriguing dual-emission patterns via an intramolecular energy transfer (IET) state in solution. Furthermore, the IET feature of the dyads was clearly observed in the rigid state.

Salen-indium/triarylborane triads: synthesis and ratiometric emission-colour changes by fluoride ion binding.

Salen-based indium triads, [{(3-tBu)2-(5-Mes2B)2-salen}In-Me] (1) and [{(3-tBu)2-(5-Mes2Bphenyl)2-salen}In-Me] (2), bearing triarylborane (TAB) units were prepared and fully characterised by NMR spectroscopy and elemental analysis. The major absorption bands of 1 and 2 appeared in the region centred at 347 nm and 374 nm, respectively, and the intense emission spectra were observed in the sky blue (λem = 491 nm for 1) and bluish-green (λem = 498 nm for 2) regions, respectively. The solvatochromism effects in various organic solvents and computational calculation results strongly suggested that these absorption and emission features are mainly attributed to intramolecular charge transfer (ICT) transitions between the salen ligand moieties and the TAB units.

Akinete germination chamber: An experimental device for cyanobacterial akinete germination and plankton emergence.

Understanding how algal resting cells (e.g. akinetes) germinate and what factors influence their germination rate is crucial for elucidating the development of algal blooms and their succession.

Defect Engineering into Metal-Organic Frameworks for the Rapid and Sequential Installation of Functionalities.

Postsynthetic treatments are well-known and important functionalization tools of metal-organic frameworks (MOFs). Herein, we have developed a practical and rapid postsynthetic ligand exchange (PSE) strategy using a defect-controlled MOF. An increase in the number of defects amounts to MOFs with enhanced rates of ligand exchange in a shorter time frame.

Synthesis and Dual-Emission Feature of Salen-Al/Triarylborane Dyads.

Novel salen-Al/triarylborane dyad complexes were prepared and characterized with their corresponding mononuclear compounds. The UV-vis and photoluminescence experiments for dyads exhibited photoinduced energy transfer from borane to the salen-Al moiety in an intramolecular manner. Theoretical calculation and fluoride titration results further supported these intramolecular energy-transfer features.

Intriguing Indium-salen Complexes as Multicolor Luminophores.

The series of novel salen-based indium complexes (3-Bu-5-R-salen)In-Me (3-Bu-5-R-salen = N,N'-bis(2-oxy-3-tert-butyl-5-R-salicylidene)-1,2-diaminoethane, R = H (1), Bu (2), Br (3), Ph (4), OMe (5), NMe (6)) and [(3-Bu-5-NMe-salen)In-Me](OTf) (7; OTf = CFSO) have been synthesized and fully characterized by NMR spectroscopy and elemental analysis. All indium complexes 1-7 are highly stable in air and even aqueous solutions. The solid-state structures for 3-5, which were confirmed by single-crystal X-ray analysis, exhibit square-pyramidal geometries around the indium center.

Novel aluminum-BODIPY dyads: intriguing dual-emission via photoinduced energy transfer.

Three novel BODIPY-based heterodinuclear complexes, [salen(3,5-(t)Bu)2Al-(OC6H4-BODIPY)] (6), [salen(3,5-(t)Bu)2Al-(OC6F2H2-BODIPY)] (7), and [(mq)2Al-(OC6H4-BODIPY)] (8) (salen = N,N'-bis(salicylidene)ethylenediamine, BODIPY = 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene, and mq = methyl-8-quinolinolato) were prepared and characterized by multinuclear NMR spectroscopy. The specific structures of 6-8 were also determined by single crystal X-ray analysis. In particular, the salen-based heterodinuclear complexes 6 and 7 exhibited higher thermal stability (Td5 = 309 and 306 °C, respectively) than that of the closely related mononuclear aluminum or BODIPY compounds, except for 8.