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Purpose: Both super(131)I- and super(123)I-labeled meta-iodobenzylguanidine (MIBG) have been widely used in the clinic for targeted imaging of the norepinephrine transporter (NET). The human NET (hNET) gene has been imaged successfully with super(124)I-MIBG positron emission tomography (PET) at time points of >24 h post-injection (p.i.). super(18)F-labeled MIBG analogs may be ideal to image hNET expression at time points of <8 h p.i. We developed improved methods for the synthesis of known MIBG analogs, [ super(18)F]MFBG and [ super(18)F]PFBG and evaluated them in hNET reporter gene-transduced C6 rat glioma cells and xenografts. Methods: [ super(18)F]MFBG and [ super(18)F]PFBG were synthesized manually using a three-step synthetic scheme. Wild-type and hNET reporter gene-transduced C6 rat glioma cells and xenografts were used to comparatively evaluate the super(18)F-labeled analogs with [ super(123)I]/[ super(124)I] MIBG. Results: The fluorination efficacy on benzonitrile was predominantly determined by the position of the trimethylammonium group. The para-isomer afforded higher yields (75 plus or minus 7 %) than meta-isomer (21 plus or minus 5 %). The reaction of [ super(18)F]fluorobenzylamine with 1H-pyrazole-1-carboximidamide was more efficient than with 2-methyl-2-thiopseudourea. The overall radiochemical yields (decay-corrected) were 11 plus or minus 2 % (n=12) for [ super(18)F]MFBG and 41 plus or minus 12 % (n=5) for [ super(18)F]PFBG, respectively. The specific uptakes of [ super(18)F]MFBG and [ super(18)F]PFBG were similar in C6-hNET cells, but 4-fold less than that of [ super(123)I]/[ super(124)I] MIBG. However, in vivo [ super(18)F]MFBG accumulation in C6-hNET tumors was 1.6-fold higher than that of [ super(18)F]PFBG at 1 h p.i., whereas their uptakes were similar at 4 h. Despite [ super(18)F]MFBG having a 2.8-fold lower affinity to hNET and approximately 4-fold lower cell uptake in vitro compared to [ super(123)I]/[ super(124)I] MIBG, PET imaging demonstrated that [ super(18)F]MFBG was able to visualize C6-hNET xenografts better than [ super(124)I]MIBG. Biodistribution studies showed [ super(18)F]MFBG and super(123)I-MIBG had a similar tumor accumulation, which was lower than that of no-carrier-added [ super(124)I]MIBG, but [ super(18)F]MFBG showed a significantly more rapid body clearance and lower uptake in most non-targeting organs. Conclusion: [ super(18)F]MFBG and [ super(18)F]PFBG were synthesized in reasonable radiochemical yields under milder conditions. [ super(18)F]MFBG is a better PET ligand to image hNET expression in vivo at 1-4 h p.i. than both [ super(18)F]PFBG and [ super(123)I]/[ super(124)I] MIBG.

Aromatic molecules such as polycyclic aromatic hydrocarbons (PAHs) are known to exist in the interstellar medium owing to their characteristic infrared emission features. However, the infrared emission only indicates the general class of molecule, and identifying which specific molecular species are present is difficult. McGuire et al. used radio astronomy to detect rotational transitions of benzonitrile emitted from a well-known nearby cloud of interstellar gas (see the Perspective by Joblin and Cernicharo). This molecule may be a precursor to more complex PAHs. The identification of benzonitrile sheds light on the composition of aromatic material within the interstellar medium—material that will eventually be incorporated into new stars and planets. Science , this issue p. 202 ; see also p. 156 Radio astronomy is used to identify the aromatic molecule benzonitrile in the interstellar medium. Polycyclic aromatic hydrocarbons and polycyclic aromatic nitrogen heterocycles are thought to be widespread throughout the universe, because these classes of molecules are probably responsible for the unidentified infrared bands, a set of emission features seen in numerous Galactic and extragalactic sources. Despite their expected ubiquity, astronomical identification of specific aromatic molecules has proven elusive. We present the discovery of benzonitrile ( c -C 6 H 5 CN), one of the simplest nitrogen-bearing aromatic molecules, in the interstellar medium. We observed hyperfine-resolved transitions of benzonitrile in emission from the molecular cloud TMC-1. Simple aromatic molecules such as benzonitrile may be precursors for polycyclic aromatic hydrocarbon formation, providing a chemical link to the carriers of the unidentified infrared bands.

In this paper, based on the structure model of D-π-A, carbazole and phenimidazole are used as the building blocks of blue molecules, and benzonitrile group is added to N (1) position of the imidazole ring, and tert-butyl group is added to the 3 and 6 positions of carbazole to change the length of the bridge bond. Synthesized two novel blu-ray molecular: 4 - (2 - (4 - (3, 6-2 tertiary butyl - 9 h - carbazole - 9 - base) phenyl) 1 h - fe [9, 10 - d] imidazole - 1 - base) phenyl nitrile (NCPPIM - CzBu A) and 4 - (2 - (4 ’- (3, 6-2 tertiary butyl - 9 h - carbazole - 9 - base) - [1, 1’ - biphenyls] - 4 -) 1 h - fe [9, 10 - d] imidazole - 1 - base) phenyl nitrile (NCPPIM - CzBu B). Their structure and properties were characterized and analyzed, and the influence of the bridge bond of monophenone ring and diphenyl ring on the molecular properties of blue light was explored. The experimental results showed that monophenone ring (NCPPIM-CzBu A) showed better morphological stability than diphenyl (NCPPIM-CzBu B), and NCPPIM-CzBu B had higher fluorescence quantum yield. The fluorescence quantum yield of NCPPIM-CzBu B is 9.31 % higher than that of NCPPIM-CzBu A. The results show that the reasonable selection of monophenone and diphenyl ring with bridge bond plays an important role in the synthesis of suitable blue molecules, and provides a new way for the synthesis of novel blue molecules.

Photocatalytic hydrogen peroxide (H 2 O 2 ) generation represents a promising approach for artificial photosynthesis. However, the sluggish half-reaction of water oxidation significantly limits the efficiency of H 2 O 2 generation. Here, a benzylamine oxidation with more favorable thermodynamics is employed as the half-reaction to couple with H 2 O 2 generation in water by using defective zirconium trisulfide (ZrS 3 ) nanobelts as a photocatalyst. The ZrS 3 nanobelts with disulfide (S 2 2− ) and sulfide anion (S 2− ) vacancies exhibit an excellent photocatalytic performance for H 2 O 2 generation and simultaneous oxidation of benzylamine to benzonitrile with a high selectivity of >99%. More importantly, the S 2 2− and S 2− vacancies can be separately introduced into ZrS 3 nanobelts in a controlled manner. The S 2 2− vacancies are further revealed to facilitate the separation of photogenerated charge carriers. The S 2− vacancies can significantly improve the electron conduction, hole extraction, and kinetics of benzylamine oxidation. As a result, the use of defective ZrS 3 nanobelts yields a high production rate of 78.1 ± 1.5 and 32.0 ± 1.2 μmol h −1 for H 2 O 2 and benzonitrile, respectively, under a simulated sunlight irradiation. Photocatalytic H 2 O 2 generation represents a promising approach for artificial photosynthesis. Here, ZrS 3 nanobelts with controllable disulfide and sulfide anion vacancies exhibit an excellent photocatalytic H 2 O 2 generation performance together with selective oxidation of benzylamine to benzonitrile.

Blue thermally activated delayed fluorescent emitters are promising for the next generation of organic light-emitting diodes, yet their performance still cannot meet the requirements for commercialization. Here we establish a design rule for highly efficient and stable thermally activated delayed fluorescent emitters by introducing an auxiliary acceptor that could delocalize electron distributions, enhancing molecular stability in both the negative polaron and triplet excited state, while also accelerating triplet-to-singlet up-conversion and singlet radiative processes simultaneously. Proof-of-concept thermally activated delayed fluorescent compounds, based on a multi-carbazole-benzonitrile structure, exhibit near-unity photoluminescent quantum yields, short-lived delays and improved photoluminescent and electroluminescent stabilities. A deep-blue organic light-emitting diode using one of these molecules as a sensitizer for a multi-resonance emitter achieves a remarkable time to 95% of initial luminance of 221 h at an initial luminance of 1,000 cd m −2 , a maximum external quantum efficiency of 30.8% and Commission Internationale de l’Eclairage coordinates of (0.14, 0.17). The stability and efficiency of thermally activated delayed fluorescent (TADF) emitters are still limited. Here the authors design TADF compounds by introducing an auxiliary acceptor with both enhanced stability and enhanced efficiency.

Hydrogenation of nitriles represents as an atom-economic route to synthesize amines, crucial building blocks in fine chemicals. However, high redox potentials of nitriles render this approach to produce a mixture of amines, imines and low-value hydrogenolysis byproducts in general. Here we show that quasi atomic-dispersion of Pd within the outermost layer of Ni nanoparticles to form a Pd 1 Ni single-atom surface alloy structure maximizes the Pd utilization and breaks the strong metal-selectivity relations in benzonitrile hydrogenation, by prompting the yield of dibenzylamine drastically from ∼5 to 97% under mild conditions (80 °C; 0.6 MPa), and boosting an activity to about eight and four times higher than Pd and Pt standard catalysts, respectively. More importantly, the undesired carcinogenic toluene by-product is completely prohibited, rendering its practical applications, especially in pharmaceutical industry. Such strategy can be extended to a broad scope of nitriles with high yields of secondary amines under mild conditions. While nitrile hydrogenation may provide an appealing means to obtain secondary amines, poor selectivity plagues heterogeneous catalysts. Here, authors report single-atom palladium on nickel catalysts to afford high yields of secondary amines from a broad range of parent nitriles.

Pure-organic red exciplex emitters are far from satisfactory in terms of quantity and efficiency. The narrow lowest unoccupied molecular orbital (LUMO) energy levels range of reported acceptors together with the intrinsic exciton non-radiative decay are the dominant factors restricting the progress of red exciplexes. Herein, two acceptor molecules operating at unique LUMO of -3.51 and -3.56 eV, namely 4-(6-([1, 1’: 3’, 1”-terphenyl]-5’-yl)-1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl) benzonitrile (CNAI-tPh) and 4-(6-(4-(4, 6-diphenyl-1, 3, 5-triazin-2-yl)phenyl)-1, 3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl) benzonitrile (CNAI-TRz), were developed. Through binding to a donor whose HOMO energy level is -5.53 eV, the CNAI-TRz-related OLEDs attained a higher device efficiency amounting to 7.7% with a red-shifted spectrum compared to the CNAI-tPh-related devices. These results are remarkable among the reported pure-organic red exciplex-based OLEDs and demonstrate the tremendous potential of our synthesized acceptors in efficient red exciplexes.

4-Methylsulfonyl-benzonitrile is an organic compound used in organic synthesis with applications in medicine, dye, and pesticide production. However, its toxicological characteristics in humans remain poorly understood, with no previously reported cases of poisoning. This report describes a 33-year-old male who developed severe toxic encephalopathy and peripheral neuropathy following occupational exposure during herbicide production. The patient worked without adequate personal protective equipment in a workshop where he was intermittently exposed to organic solvents, including 4-methylsulfonyl-benzonitrile, over several months. He initially presented with dizziness, slurred speech, and mental deterioration, which progressed to impaired consciousness and respiratory failure requiring mechanical ventilation. Blood analysis revealed an initial 4-methylsulfonyl-benzonitrile concentration of 734 ng/mL upon initial testing, decreasing to 76 ng/mL, and becoming undetectable within 10 days. Magnetic resonance imaging showed diffuse symmetric abnormalities in the corpus callosum, bilateral basal ganglia, corona radiata, and centrum semiovale. Electromyography confirmed sensorimotor peripheral neuropathy. The patient received comprehensive treatment including mechanical ventilation, organ protection, neurotrophic therapy, anti-infective therapy, and nutritional support. After 28 days of hospitalization, he was discharged with significant improvement-conscious, oriented, and with normalized speech, although mild numbness in the limbs persisted. This case demonstrates that 4-methylsulfonyl-benzonitrile poisoning can induce both toxic encephalopathy and peripheral neuropathy. The findings highlight an urgent need to strengthen safety monitoring and safety training in chemical manufacturing enterprises.

Aryl thianthrenium salts are valuable in photocatalysis but traditionally require external electron donors for activation. This study introduces an energy transfer (EnT) strategy for the activation of aryl thianthrenium salts using 2,3,4,5,6-penta(carbazol-9-yl)benzonitrile (5CzBN) as a metal-free photocatalyst, eliminating the need for external donors. Utilizing this EnT approach, we achieve C–H deuteration of arenes under visible light with CDCl 3 as a deuterium source to synthesize various deuterated aromatic compounds, including important natural products and pharmaceuticals. Additionally, this strategy enables diverse functionalizations including borylation, arylation, cyanation, and selenylation, enhancing the applicability of aryl sulfonium salts in environmentally friendly photocatalysis. Aryl thianthrenium salts are valuable in photocatalysis but traditionally require external electron donors for activation. Herein, the authors report an energy transfer strategy for the activation of aryl thianthrenium salts, eliminating the need for external donors.

Checkpoint inhibitors such as PD-1/PD-L1 antibody therapeutics are a promising option for the treatment of multiple cancers. Due to the inherent limitations of antibodies, great efforts have been devoted to developing small-molecule PD-1/PD-L1 signaling pathway inhibitors. In this study we established a high-throughput AlphaLISA assay to discover small molecules with new skeletons that could block PD-1/PD-L1 interaction. We screened a small-molecule library of 4169 compounds including natural products, FDA approved drugs and other synthetic compounds. Among the 8 potential hits, we found that cisplatin, a first-line chemotherapeutic drug, reduced AlphaLISA signal with an EC 50 of 8.3 ± 2.2 μM. Furthermore, we showed that cisplatin-DMSO adduct, but not semplice cisplatin, inhibited PD-1/PD-L1 interaction. Thus, we assessed several commercial platinum (II) compounds, and found that bis(benzonitrile) dichloroplatinum (II) disturbed PD-1/PD-L1 interaction (EC 50  = 13.2 ± 3.5 μM). Its inhibitory activity on PD-1/PD-L1 interaction was confirmed in co-immunoprecipitation and PD-1/PD-L1 signaling pathway blockade bioassays. Surface plasmon resonance assay revealed that bis(benzonitrile) dichloroplatinum (II) bound to PD-1 ( K D  = 2.08 μM) but not PD-L1. In immune-competent wild-type mice but not in immunodeficient nude mice, bis(benzonitrile) dichloroplatinum (II) (7.5 mg/kg, i.p., every 3 days) significantly suppressed the growth of MC38 colorectal cancer xenografts with increasing tumor-infiltrating T cells. These data highlight that platinum compounds are potential immune checkpoint inhibitors for the treatment of cancers.