Regulating Perovskite Crystallization through Interfacial Engineering Using a Zwitterionic Additive Potassium Sulfamate for Efficient Pure-Blue Light-Emitting Diodes.

Quasi-two-dimensional (quasi-2D) perovskites are emerging as efficient emitters in blue perovskite light-emitting diodes (PeLEDs), while the imbalanced crystallization of the halide-mixed system limits further improvements in device performance. The rapid crystallization caused by Cl doping produces massive defects at the interface, leading to aggravated non-radiative recombination. Meanwhile, unmanageable perovskite crystallization is prone to facilitate the formation of nonuniform low-dimensional phases, which results in energy loss during the exciton transfer process. Here, we propose a multifunctional interface engineering for nucleation and phase regulation by incorporating the zwitterionic additive potassium sulfamate into the hole transport layer. By using potassium ions (K+ ) as heterogeneous nucleation seeds, finely controlled growth of interfacial K+ -guided grains is achieved. The sulfamate ions can simultaneously regulate the phase distribution and passivate defects through coordination interactions with undercoordinated lead atoms. Consequently, such synergistic effect constructs quasi-2D blue perovskite films with smooth energy landscape and reduced trap states, leading to pure-blue PeLEDs with a maximum external quantum efficiency (EQE) of 17.32 %, spectrally stable emission at 478 nm and the prolonged operational lifetime. This work provides a unique guide to comprehensively regulate the halide-mixed blue perovskite crystallization by manipulating the characteristics of grain-growth substrate.

Comprehensive Crystal Regulation Reduces Interfacial Energy Loss for Efficient Blue Perovskite Light-Emitting Diodes.

As an essential component of future full-color displays, blue perovskite light-emitting diodes (PeLEDs) still lag far behind the red and green counterparts in the device performances. In the mainstream quasi-2D blue perovskite system, trap-mediated nonradiative loss, low energy transfer efficiency, and interface fluorescence quenching remain significant challenges. Herein, guanidinium thiocyanate (GASCN) and potassium cinnamate (PCA) are respectively introduced into the hole transport layer (HTL) and the perovskite precursor to achieve a dense and uniform perovskite thin film with greatly improved optoelectronic properties. Therefore, adequate GA+ acts as pre-nucleation sites on the HTL surface, regulating crystallization through strong hydrogen bonding with perovskite intermediates. The realized polydisperse domain distribution is conducive to cascade energy transfer, and the improved hole transport ability alleviates interface fluorescence quenching. In addition, the SCN- and CA- groups can form coordination bonds with the defects at the buried perovskite interface and grain boundaries, respectively, which effectively suppresses the detrimental nonradiative recombination. Benefitting from the comprehensive crystal regulation, blue PeLEDs featuring stable emission at 484 and 468 nm exhibit improved external quantum efficiencies of 11.5% and 4.3%, respectively.

Research and Application of Shallow Geothermal Energy Development and Utilization in Shandong Province.

Shallow geothermal energy reserves are abundant and widely distributed in Shandong Province. Vigorously developing and utilizing shallow geothermal energy will play a significant role in improving energy pressure in Shandong Province. The energy efficiency of ground source heat pumps is closely related to geological and other conditions. However, few studies on geothermal exploitation and utilization have been affected by economic policies. This article will investigate the operation of shallow geothermal engineering in Shandong Province, summarize the current number of operating projects, calculate the engineering annual comprehensive performance coefficient (ACOP), analyze the size characteristics of different cities, and analyze their correlation with economy and policy. Through research, it is found that the number of shallow geothermal energy development and utilization is significantly positively correlated with socioeconomic level and policy orientation, and has a relatively small relationship with ACOP. The research results provide a basis and suggestions for improving and optimizing the energy efficiency coefficient of geothermal heat pumps and promoting the development and utilization of shallow geothermal.

Bruceine D Acts as a Potential Insecticide by Antagonizing 20E-EcR/USP Signal Transduction.

Bruceine D (BD) is an effective insecticidal compound found in the Chinese herb Brucea javanica (L.) Merr. BD inhibits the growth and metamorphosis of Plutella xylostella and Drosophila melanogaster; however, its target protein and the molecular mechanism of insecticidal activity remain unclear. In this study, proteins with high affinity for BD were screened using surface plasmon resonance and high-performance liquid chromatography coupled with matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry, revealing the ecdysone receptor (EcR) is the main target of BD. In vivo results showed that BD inhibited insect growth and metamorphosis through inhibition of the expression of 20E response genes. In vitro dual luciferase and enhanced green fluorescent protein (EGFP) fluorescence experiments indicated that BD suppressed the transcriptional activation activity of EcR by blocking the ecdysone response element (EcRE)-triggered transcriptional cascade, suggesting that BD inhibits the formation of the 20E-EcR-USP-EcRE complex. Moreover, molecular docking demonstrated that BD bound well to EcR. Elucidating the insecticidal mechanism of BD will be helpful in the development of green pesticides to control pests.

Coordinating Etching Inspired Synthesis of Fe(OH)3 Nanocages as Mimetic Peroxidase for Fluorescent and Colorimetric Self-Tuning Detection of Ochratoxin A.

The development of multifunctional biomimetic nanozymes with high catalytic activity and sensitive response is rapidly advancing. The hollow nanostructures, including metal hydroxides, metal-organic frameworks, and metallic oxides, possess excellent loading capacity and a high surface area-to-mass ratio. This characteristic allows for the exposure of more active sites and reaction channels, resulting in enhanced catalytic activity of nanozymes. In this work, based on the coordinating etching principle, a facile template-assisted strategy for synthesizing Fe(OH)3 nanocages by using Cu2O nanocubes as the precursors was proposed. The unique three-dimensional structure of Fe(OH)3 nanocages endows it with excellent catalytic activity. Herein, in the light of Fe(OH)3-induced biomimetic nanozyme catalyzed reactions, a self-tuning dual-mode fluorescence and colorimetric immunoassay was successfully constructed for ochratoxin A (OTA) detection. For the colorimetric signal, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) can be oxidized by Fe(OH)3 nanocages to form a color response that can be preliminarily identified by the human eye. For the fluorescence signal, the fluorescence intensity of 4-chloro-1-naphthol (4-CN) can be quantitatively quenched by the valence transition of Ferric ion in Fe(OH)3 nanocages. Due to the significant self-calibration, the performance of the self-tuning strategy for OTA detection was substantially enhanced. Under the optimized conditions, the developed dual-mode platform accomplishes a wide range of 1 ng/L to 5 µg/L with a detection limit of 0.68 ng/L (S/N = 3). This work not only develops a facile strategy for the synthesis of highly active peroxidase-like nanozyme but also achieves promising sensing platform for OTA detection in actual samples.

Effects of Cycloplegic Agents on Ocular Parameters in Children with Myopia and Hyperopia.

Background: To study the effect of cycloplegia on ocular parameters in children with myopia and hyperopia. Methods: Forty-two myopia and forty-four hyperopia eyes in children between 5 and 10 years of age were included. Measurements were taken before and after cycloplegia using 1% atropine sulfate ointment. The ocular parameters included central corneal thickness (CCT), corneal curvature (CC), anterior chamber depth (ACD), pupil diameter (PD), axial length (AL), and central retinal thickness (CRT). Results: There was no significant difference in CCT, CC, and CRT between the two groups without cycloplegia, but the ACD of the myopia (3.64 ± 0.28 mm) group was significantly higher than that of hyperopia (3.40 ± 0.24 mm; t = -4.522; P < 0.0001). The average PD of the myopia (4.85 ± 0.87 mm) group was significantly smaller than that of the hyperopia group (5.47 ± 1.15 mm; t = 2.903; P < 0.0046). The average AL of myopia (24.25 ± 0.77 mm) was significantly higher than that of hyperopia (21.73 ± 1.24 mm; t = 12.084; P < 0.0001). However, it was found that the average PD of myopia (7.68 ± 0.51 mm) was significantly larger than that of hyperopia (7.41 ± 0.57 mm; t = 2.364; P=0.0202) under cycloplegia. As for the changes in refractive factors before and after cycloplegia, deepened ACD and enlarged PD were noted in both the groups after cycloplegia. Conclusions: Cycloplegia not only affects ACD and PD but also leads to the reversal of PD differences between the two groups. Cycloplegia effects enabled us to study changes in all known ocular parameters in a short period.

Approaching the Dimerization Mechanism of Small Molecule Inhibitors Targeting PD-L1 with Molecular Simulation.

Inhibitors blocking the PD-1/PD-L1 immune checkpoint demonstrate impressive anti-tumor immunity, and small molecule inhibitors disclosed by the Bristol-Myers Squibb (BMS) company have become a hot topic. In this work, by modifying the carbonyl group of BMS-202 into a hydroxyl group to achieve two enantiomers (MS and MR) with a chiral center, we found that this is an effective way to regulate its hydrophobicity and thus to reduce the negative effect of polar solvation free energy, which enhances the stability of PD-L1 dimer/inhibitor complexes. Moreover, we studied the binding modes of BMS-200 and BMS-202-related small molecule inhibitors by molecular dynamics simulation to explore their inhibitory mechanism targeting PD-L1 dimerization. The results showed that the size exclusion effect of the inhibitors triggered the rearrangement of the residue ATyr56, leading to the formation of an axisymmetric tunnel-shaped pocket, which is an important structural basis for improving the binding affinity of symmetric inhibitors with PD-L1. Furthermore, after inhibitor dissociation, the conformation of ATyr123 and BMet115 rearranged, which blocked the entrance of the binding pocket, while the reverse rearrangements of the same residues occurred when the PD-L1 monomer was complexed with the inhibitors, preparing PD-L1 for dimerization. Overall, this study casts a new light on the inhibitory mechanism of BMS inhibitors targeting PD-L1 dimerization and provides an idea for designing novel small molecule inhibitors for future cancer immunotherapy.

Is the Triggering of PD-L1 Dimerization a Potential Mechanism for Food-Derived Small Molecules in Cancer Immunotherapy? A Study by Molecular Dynamics.

Using small molecules to inhibit the PD-1/PD-L1 pathway is an important approach in cancer immunotherapy. Natural compounds such as capsaicin, zucapsaicin, 6-gingerol and curcumin have been proposed to have anticancer immunologic functions by downregulating the PD-L1 expression. PD-L1 dimerization promoted by small molecules was recently reported to be a potential mechanism to inhibit the PD-1/PD-L1 pathway. To clarify the molecular mechanism of such compounds on PD-L1 dimerization, molecular docking and molecular dynamics simulations were performed. The results evidenced that these compounds could inhibit PD-1/PD-L1 interactions by directly targeting PD-L1 dimerization. Binding free energy calculations showed that capsaicin, zucapsaicin, 6-gingerol and curcumin have strong binding ability with the PD-L1 dimer, where the affinities of them follow the trend of zucapsaicin > capsaicin > 6-gingerol ≈ curcumin. Analysis by residue energy decomposition, contact numbers and nonbonded interactions revealed that these compounds have a tight interaction with the C-sheet, F-sheet and G-sheet fragments of the PD-L1 dimer, which were also involved in the interactions with PD-1. Moreover, non-polar interactions between these compounds and the key residues Ile54, Tyr56, Met115 and Ala121 play a key role in stabilizing the protein−ligand complexes in solution, in which the 4'-hydroxy-3'-methoxyphenyl group and the carbonyl group of zucapsaicin, capsaicin, 6-ginger and curcumin were significant for the complexation of small molecules with the PD-L1 dimer. The conformational variations of these complexes were further analyzed by free energy landscape (FEL) and principal component analysis (PCA) and showed that these small molecules could make the structure of dimers more stable. This work provides a mechanism insight for food-derived small molecules blocking the PD-1/PD-L1 pathway via directly targeting the PD-L1 dimerization and offers theoretical guidance to discover more effective small molecular drugs in cancer immunotherapy.

Azocalixarene-Based Supramolecular System for the Detection of Paraquat via an Improved Indicator Displacement Assay.

In view of the lethal toxicity of paraquat (PQ) on human health, herein, a simple indicator displacement assay (IDA) based on an azo-modified calixarene host (azoCX[4]) and a fluorophore guest (p-DPD) were elaborately constructed for PQ detection in environmental water samples and plant surfaces. The fluorescent signal of p-DPD in the probe can be quenched by azoCX[4] through a photon-induced electron transfer process and recovered upon the addition of PQ within 10 s. The detection range of the p-DPD@azoCX[4] probe was calculated to be 0.35-8 µM in the Tris-HCl buffer solutions (pH = 7.4). Moreover, this probe exhibited excellent detection selectivity toward PQ over five herbicides (glyphosate, bispyribac, atrazine, ametryn, and bensulfuron methyl), together with anti-interference abilities in the presence of inorganic ions (K+, Na+, Zn2+, Ni2+, Li+, F-, Cl-, Br-, CO32-, HCO3-, and NO3-) and amino acids (Asp, Arg, Glu, Ala, and Cys). Particularly, the probe was successfully used to detect PQ in real water samples with acceptable accuracy and showed potential applications for on-site detection with paper-based test strips and on the leaf surface. We believe that this simplified IDA-based probe provided an effective detecting tool for PQ, and the design strategy would guide the further development of new IDA sensing systems.

Design of new glycosyl-O-fipronil conjugates with improved hydrolysis efficiency assisted by molecular simulations.

BACKGROUND: In a previous study, we showed that two glycosyl-pesticide conjugates with a ß-d-glucoside moiety, N-{3-cyano-1-[2,6-dichloro-4-(trifluoromethyl) phenyl]-4-[(trifluoromethyl)-sulfinyl]-1H-pyrazol-5-yl}-2-aminoethyl-ß-d-glucopyranoside (GOF) and N-{3-cyano-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl) sulfinyl]-1H-pyrazol-5-yl}-1-(2-triazolethyl-ß-d-glucopyranoside)-1H-1,2,3-triazole-4-methanamine (GOTF), can move in the phloem and be hydrolyzed by ß-glucosidase at different rates. Simulations were carried out to investigate differences in the hydrolysis process in GOF, GOTF and p-nitrophenyl ß-d-glucopyranoside (pNPG). A new series of glycosyl-O-fipronil conjugates was then designed and synthesized based on the simulation results. The phloem mobilities of the new conjugates were examined using a Ricinus model, and their hydrolysis efficiencies based on ß-glucosidase were determined. RESULTS: New glycosyl-O-fipronil conjugates GOE2-6 were designed and synthesized. To reduce steric hindrance, the conjugating site of the glycone moiety was moved to the 4'-sulfonyl group on the pyrrole ring. As a result, the hydrolysis efficiencies of the new conjugates were significantly improved, with GOE4 having the highest hydrolysis efficiency. All five conjugates could be transported in Ricinus phloem sap, consistent with previously studied glycosyl-O-fipronil conjugates. The insecticidal activities of the conjugates were tested against Plutella xylostella. CONCLUSION: A strategy for the development of new phloem-mobile pesticides was proposed: linking a glycosyl group to the existing pesticide structure with a linear alkyl connection approximately four carbons in length. The resultant conjugates feature not only good phloem mobility, but also potential high bioactivity due to the efficient release of active pesticide components under the action of glucosidase. © 2022 Society of Chemical Industry.

Molecular Mechanism of Small-Molecule Inhibitors in Blocking the PD-1/PD-L1 Pathway through PD-L1 Dimerization.

Programmed cell death-1 (PD-1), which is a molecule involved in the inhibitory signal in the immune system and is important due to blocking of the interactions between PD-1 and programmed cell death ligand-1 (PD-L1), has emerged as a promising immunotherapy for treating cancer. In this work, molecular dynamics simulations were performed on complex systems consisting of the PD-L1 dimer with (S)-BMS-200, (R)-BMS-200 and (MOD)-BMS-200 (i.e., S, R and MOD systems) to systematically evaluate the inhibitory mechanism of BMS-200-related small-molecule inhibitors in detail. Among them, (MOD)-BMS-200 was modified from the original (S)-BMS-200 by replacing the hydroxyl group with a carbonyl to remove its chirality. Binding free energy analysis indicates that BMS-200-related inhibitors can promote the dimerization of PD-L1. Meanwhile, no significant differences were observed between the S and MOD systems, though the R system exhibited a slightly higher energy. Residue energy decomposition, nonbonded interaction, and contact number analyses show that the inhibitors mainly bind with the C, F and G regions of the PD-L1 dimer, while nonpolar interactions of key residues Ile54, Tyr56, Met115, Ala121 and Tyr123 on both PD-L1 monomers are the dominant binding-related stability factors. Furthermore, compared with (S)-BMS-200, (R)-BMS-200 is more likely to form hydrogen bonds with charged residues. Finally, free energy landscape and protein-protein interaction analyses show that the key residues of the PD-L1 dimer undergo remarkable conformational changes induced by (S)-BMS-200, which boosts its intimate interactions. This systematic investigation provides a comprehensive molecular insight into the ligand recognition process, which will benefit the design of new small-molecule inhibitors targeting PD-L1 for use in anticancer therapy.

Nanoindentation and Hierarchy Structure of the Bovine Hoof Wall.

The bovine hoof wall with an α-keratin structure protects the bovine foot from impact loads when the cattle are running. Reduced modulus, hardness and creep behavior of the bovine hoof wall have been investigated by a nanoindentation technique. The average reduced modulus of the Transverse Direction (TD) specimens from the outside to inside wall is 3.76 and 2.05 GPa, respectively, while the average reduced modulus of the Longitudinal Direction (LD) specimens from the outside to inside wall is 4.54 and 3.22 GPa, respectively. Obviously, the orientation and the position of the bovine hoof wall have a significant influence on its mechanical properties. The use of the generalized Voigt-Kelvin model can make a good prediction of creep stage. Mechanical properties of the LD specimens are stronger than those of the TD specimens. The bovine hoof wall has a layered structure, which can effectively absorb the energy released by the crack propagation and passivate the crack tip. Therefore, a kind of structural model was designed and fabricated by three-dimensional printing technology, which has a 55% performance improvement on fracture toughness. It is believed that the reported results can be useful in the design of new bionic structure materials which may be used in motorcycle helmets and athletes' protective equipment to achieve light weight and improved strength at the same time.

Mechanical Properties and Serration Behavior of a NiCrFeCoMn High-Entropy Alloy at High Strain Rates.

Serration behavior is a kind of plastic instability phenomenon of materials, which widely exists in the high-entropy alloys and has influence on microstructure and mechanical properties. In this work, the microstructure and mechanical properties of a NiCrFeCoMn high-entropy alloy (HEA) were studied under high-speed impact. The microstructure of a NiCrFeCoMn HEA were investigated by optical microscope (OM), scanning electron microscope (SEM), electron backscatter diffraction (EBSD), and transmission electron microscope (TEM). The dislocation density increased with the true strain at high-strain-rate deformation, and the dislocations can be hindered and released continually by the twin layers, resulting in serration on the true stress-true strain curve. When values of the strain rates are 1250, 2000 and 4800 s-1, the yield strength of the deformed NiCrFeCoMn HEA are 510, 525 and 680 MPa, respectively. Moreover, the fluctuation of the serration became more serious with the increasing of the strain rate. Compared with the as-cast NiCrFeCoMn HEA, the true stress-true strain curve of the deformed NiCrFeCoMn HEAwas smoother.

Microstructure and mechanical properties of an alpha keratin bovine hoof wall.

Bovine hoof wall with an alpha keratin structure, as the interface between the ground and the body, can protect the bony skeleton from the impact and the destruction. Microstructure and mechanical properties of the bovine hoof wall are investigated by scanning electron microscope (SEM), transmission electron microscope (TEM) and quasi-static mechanical tests. Mechanical results show that the mean J-integral values of the LD specimens parallel to the tubular axis are higher than those of the TD specimens normal to the tubular axis, and the fracture toughness reaches the peak values (21 kJ/m2, 33 kJ/m2 for the TD and the LD specimens, respectively) at 16.5% moisture content. The morphology results show that the laminated keratin structure can form the extensive strain-transition interfaces and the tubules played an important role in twisting crack propagation. Angles of the laminated structures within the inter-tubular materials are not a uniform distribution varying from 0° to 90° against to the tubular axis. The interlocking interface in the tubular structure can provide increased the contact area and contribute to the bonding strength between the layers. We also propose models to illustrate the morphological structure and the crack propagation mechanism of the bovine hoof wall. This structure with the strong fracture resistance ability will provide a new inspiration for design of structural materials and architectures.

The application of pseudotargeted metabolomics method for fruit juices discrimination.

To optimize and evaluate the pseudotargeted metabolomics for juice discrimination and authentication, five widely consumed fruit (apple, orange, pear, purple grape and mandarin) juices were selected. SWATH-MS data was acquired by various windows being calculated based on total ion current, and then 2310 and 2292 MRM transitions were generated. Most of them (1522 and 1872) were detected in positive and negative modes. Distinctive separation among these juices could be observed from principal component analysis and hierarchical clustering analysis. After analysis of variance, fold change analysis and orthogonal projection to latent structures discriminant analysis, 57 potential markers were defined. Subsequently, 33 markers were putatively annotated, which could be used for juice discrimination and authentication. And 7 markers including l-phenylalanine, ascorbic acid, adenosine, epicatechin, glutathione, chlorogenic acid and nobiletin, were confirmed by standards. It is clearly indicated that pseudotargeted metabolomics could make great contribution to food industry as a new emerging technique.

Nanoindentation and Microstructure in the Shear Band in a Near Beta Titanium Alloy Ti-5Al-5Mo-5V-1Cr-1Fe.

Shear localization is the main deformation mode for the near beta titanium alloy Ti-5Al-5Mo-5V-1Cr-1Fe loaded at high strain rates at either room temperature or cryogenic temperature. Nanoindentation, transmission electron microscopy, and high-resolution electron microscopy technique are applied to character the microstructure features and mechanical properties in the shear band of near beta titanium alloy. A white and straight band is observed in the shear region. Both microhardness and nanoindentaion hardness in the shear region are inferior to those in matrix. The different microstructure in the edge and the center in the shear band contribute to different mechanical properties. The plasticity of the entire shear band is almost homogenous when specimens are deformed at the cryogenic temperature. Rotational dynamic recrystallization is responsible for the formation of the ultrafine grains in the shear band. The edge of the shear band is composed of elongated grains, while there are ultrafine equiaxed grains in the center of the shear band. Deformation temperature has significant influence on the process of the grain refinement and the phase transformation in the shear band (SB). The grain sizes of the shear band in the specimen deformed at room temperature are larger than those in the specimens deformed at cryogenic temperature. The shear band consists of α phase grains in the specimen deformed at room temperature, and the shear band consists of α phase and lath-like α' phase grains in the specimen deformed at cryogenic temperature. Finally, the mechanisms for phase transformation in the shear band are illustrated.

Evaluating the hierarchical, hygroscopic deformation of the Daucus carota umbel through structural characterization and mechanical analysis.

Many physically immobile plants develop passive yet ingenious strategies for active seed dispersal through self-deformation in response to external stimuli, such as humidity. These hygroscopic deformations are usually driven by the internal heterogeneous architecture, which provides valuable, inspiring information for the development of novel actuating systems. The Daucus carota compound umbel is an interesting structure showing a distinct hygroscopic deformation that operates at hierarchical levels among these plants. Here, we investigate the structure of the primary and secondary rays of the umbel associated with their deformation through mechanical analyses. We reveal that through controlling both the cellulose microfibril angle (MFA) and lignification, the multi-level bending behavior of the umbel is achieved, which contributes to efficient seed protection and dispersal. The primary rays generally show more significant bending curvature changes than the secondary rays, and within each level, the outer rays exhibit a larger motion amplitude than the middle and inner rays. Mechanical testing and theoretical analysis support that adjusting the lignin content within the ray structure compensates for the effect of the small differences in cellulose MFA on its bending behavior, which contributes to the overall hygroscopic deformation. Findings also show that the primary outer ray can generate reaction forces that are more than 700 times its weight, which is higher than that for the pine cone scales. The new insights from this work are instructive for bioinspired designs of complex, self-deforming structures and devices. STATEMENT OF SIGNIFICANCE: The carrot (Daucus carota) compound umbels exhibit a unique hierarchical, hygroscopic deformation for seed dispersal among immobile plants. In this work, we elucidate that the multi-level bending behavior of the umbel is achieved through manipulating the cellulose microfibril angle (MFA) and lignification of the primary and secondary rays for the first time. We also discover that adjusting the degree of lignification compensates for the effect of small cellulose MFA differences on the bending behavior theoretically and experimentally. The primary outer rays deform in a highly efficient manner, in which reactions forces about more than 700 times its weight are generated. The findings presented are instructive for bioinspired designs of complex, self-deforming structures and devices.

DMSO-mediated palladium-catalyzed cyclization of two isothiocyanates via C-H sulfurization: a new route to 2-aminobenzothiazoles.

DMSO was found to activate arylisothiocyanates for self-nucleophilic addition. A subsequent intramolecular C-H sulfurization catalyzed by PdBr2 enables access to a wide range of 2-aminobenzothiazole derivatives in moderate to good yields. This is the first example of a DMSO-mediated Pd-catalyzed synthesis of 2-aminobenzothiazoles through cyclization/C-H sulfurization of two isothiocyanates.

Guided Evolution of Recombinant Bombyx mori Acetylcholinesterase II by Homology Modeling to Change Pesticide Sensitivity.

Keywords: docking; bottleneck; molecular dynamic simulation; side chain.