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Copyright of Chinese Journal of Pesticide Science / Nongyaoxue Xuebao is the property of Chinese Journal of Pesticide Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

H SB 2 sb O was added and the product was extracted with CH SB 2 sb Cl SB 2 sb , the combined organic layers were washed with brine, dried (MgSO SB 4 sb ) and evaporated. Keywords: diheteroaryl ketone; pyrido[3,4- g ]quinazoline; (pyrimidin-4-yl)(pyridin-4-yl)methanone; Grignard reagents; molecular shape; protein kinase inhibitors EN diheteroaryl ketone pyrido[3,4- g ]quinazoline (pyrimidin-4-yl)(pyridin-4-yl)methanone Grignard reagents molecular shape protein kinase inhibitors 3825 3832 8 11/01/23 20231116 NES 231116 Graph As part of our ongoing studies focused on the design and synthesis of new heteroaromatic compounds with potential- protein kinases inhibitory potencies, we recently reported the identification of pyrido[3,4- I g i ]quinazolines as nanomolar Cdc-like kinase 1 (CLK1) and Dual-specificity tyrosine-regulated kinase 1A (DYRK1A) inhibitors (Figure 1). Purification by flash column chromatography using EtOAc/MeOH (90:10) as eluent afforded compound B 12 b (47.9 mg, 0.186 mmol) in 81% yield as a beige powder; I R SB f sb i = 0.70 (EtOAc/MeOH 90:10); mp 149-150 °C. In the case of the I E i -isomer, SP 1 sp H- SP 1 sp H-NOESY showed a correlation between hydrazone NH SB 2 sb , and a 3-pyridinyl proton. [Extracted from the article]

A new N2O2‐tetradentate Schiff base ligand entitled as N,N′‐((ethane‐1,2‐diybis [oxy])bis (ethan‐2,1‐diyl))bis(3‐(4‐methoxyphenyl)prop‐2‐en‐1‐imine was prepared by direct reaction between 3‐(4‐methoxyphenyl)‐2‐propenal and 1,8‐diamino‐3,6‐dioxaoctane. After characterization of the ligand, some novel cadmium coordination compounds formulated as CdLX2 (X: Cl−, Br−, I−, N3−, SCN−and NO3−) were synthesized and characterized by physical and spectral techniques. Typically crystal structure of cadmium nitrate coordination compound was determined suggesting crystallization in monoclinic system (with space group of I2/a) and a coordination geometry of square anti‐prism around the Cd (II) ion. Moreover, CdLBr2 and CdLI2 compounds were prepared in nanostructured dimensions by sonochemical method confirmed by SEM, EDX, and XRD techniques. In continuation, thermal behavior investigation of the compounds including thermal stabilities, thermal decomposition steps, and thermo‐kinetic parameters was performed based on Coats‐Redfern equations from room temperature to 900 °C. Furthermore, all the compounds were subjected to bioassay against two Gram‐positive bacteria of Staphylococcus aureus and Bacillus subtilis, two Gram‐negative bacteria of Pseudomonas aeruginosa and Escherichia coli, and two fungal strains of Aspergillus oryzae and Candida albicans. The results showed that all the synthesized compounds act well as antimicrobial agents. DNA cleavage power of the materials was also evaluated using extracted DNA from E. coli bacterium. The cytotoxic activities of some compounds were investigated against the prostate cancer cell lines (PC3) and human umbilical vein endothelial cells (HUVEC) (as normal cells) by MTT assay and nitric oxide level evaluation method as compared with cis‐platin confirming anti‐cancer effects of them. Finally, the antioxidant properties of the N2O2‐ligand and its cadmium coordination compounds were examined by DPPH and FRAP methods suggesting all the compounds have good antioxidant activity as compared with standard samples. [ABSTRACT FROM AUTHOR]

A base medium system, generated from a synergistic reaction between Cs2 CO3 and t -BuOK, has been used for the direct carboxylation of imidazoles with CO2 in good yield. Oxygen- and thia-heterocyclic arenes also undergo the carboxylation with CO2 with the same reactivity. Density functional theory calculations show that construction of t -BuOCs in situ is an endothermic process of 38.31 kJ/mol. t -BuOCs can promote the deprotonation of substrates by forming an active C–Cs bond via a rather low HOMO (t -BuOCs)–LUMO (imidazole) gap of 0.28 eV, which favors the electrophilic insertion of CO2 by releasing 94.13 kJ/mol of heat. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Pesticide Science / Nongyaoxue Xuebao is the property of Chinese Journal of Pesticide Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The role of singlet oxygen potentially mediating increased conformational flexibility of a disulfide was investigated. Density functional theory (DFT) calculations indicate that the singlet oxygenation of 1,2‐dimethyldisulfane produces a peroxy intermediate. This intermediate adopts a structure with a longer S–S bond distance and a more planar torsional angle θ (C–S–S–C) compared with the nonoxygenated 1,2‐dimethyldisulfane. The lengthened S–S bond enables a facile rotation about the torsional angle in the semicircle region 0° < θ < 210°, that is ~5 kcal mol−1 lower in energy than the disulfane. The peroxy intermediate bears nO → σS–S and nO → σ*S–S interactions that stabilize the S–O bond but destabilize the S–S bond, which contrasts with stabilizing nS → σ*S–S hyperconjugative effects in the disulfane S–S bond. Subsequent departure of O2 from the disulfane peroxy intermediate is reminiscent of peroxy intermediates which also expel O2, yet facilitate cis‐trans isomerizations of stilbenes, hexadienes, cyanines, and carotenes. "Non‐oxidative" 1O2 interactions with a variety of bond types are currently underappreciated. We hope to raise awareness of how these interactions can help elucidate the origins of molecular twisting. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Problems / Kimya Problemləri is the property of Institute of Catalysis & Inorganic Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

N-Butyl-2,3-bis(dicyclohexylamino)cyclopropenimine (1) crystallizes from benzene and hexanes in the presence of HCl as a monobenzene solvate of the hydrochloride salt, [1H]Cl⋅C6H6 or C31H54N3 +⋅Cl⋅C6H6, in the P21/n space group. The protonation of 1 results in the generation of an aromatic structure based upon the delocalization of the cyclopropene double bond around the cyclopropene ring, giving three intermediate C--C bond lengths of 1.41 A °, and the delocalization of the imine-type C--N double bond, giving three intermediate C--N bond lengths of 1.32 A °. Ion-ion and ion-benzene packing interactions are described and illustrated. [ABSTRACT FROM AUTHOR]

More than a century old, magnesium Grignard reagents remain essential to the toolbox of organic chemists. Although similar reagents with the neighbouring group 2 metal Ca have been explored, the considerably higher polarity and reactivity of the Ca-C bond result in undesired decomposition pathways. Ca Grignard reagents have found academic interest but have never fully developed into an established synthetic tool. Recent research activities, however, provide facile access to these highly reactive organocalcium species, including in situ preparation and ball milling approaches to tackle the challenge of controlling their extreme sensitivity. Heavier Grignard reagents are not just more reactive but profit from unique chemical transformations. Insight into the transition metal-like properties of Ca, Sr and Ba is only just emerging. Considering the rapidly developing field of alkaline-earth metal-mediated catalysis, heavy Grignard reagents will probably have a bright future., (© 2023. Springer Nature Limited.)

Amides are a fundamental and widespread functional group, and are usually considered as poor electrophiles owing to resonance stabilization of the amide bond. Various approaches have been developed to address challenges in amide transformations. Nonetheless, most methods use activated amides, organometallic reagents or transition metal catalysts. Here, we report the direct alkylation of N,N-dialkyl benzamides with methyl sulfides promoted by the readily available base LDA (lithium diisopropylamide). This approach successfully achieves an efficient and selective synthesis of α-sulfenylated ketones without using transition-metal catalysts or organometallic reagents. Preliminary mechanism studies reveal that the deprotonative aroylation of methyl sulfides is promoted by the directed ortho-lithiation of the tertiary benzamide with LDA. Direct conversion of amides to ketones typically requires the use of transition metal catalysts or reactive organometallic reagents. Here the direct alkylation of benzamides with methyl sulfides using LDA as base provides access to thioalkoxyketones. [ABSTRACT FROM AUTHOR]

Fluorogenic labeling strategies have emerged as powerful tools for in vivo and in vitro imaging applications for diagnostic and theranostic purposes. Free organic chromophores (fluorescent dyes) are bright but rapidly degrade. Inorganic nanoparticles (e.g., quantum dots) are photostable but toxic to biological systems. Alternatively, dye‐doped polymer particles are promising for labeling and imaging due to their properties that overcome limitations of photodegradation and toxicity. This progress report, therefore, presents various synthesis techniques for the generation of dye‐doped fluorescent polymer particles. Polymer particles are relatively soft compared to inorganic nanoparticles and can be synthesized with characteristics like biocompatibility and stimuli responsiveness. Also, their ability of loading fluorophores through various interactions reveals brightness. Here, a multiscale‐multicolor library of bright and soft fluorescent polymer particles is generated hierarchically. Various microfluidic supported strategies have been applied where fluorophores can be linked to polymeric networks noncovalently and covalently in the interior, and at the surface of nanoparticles (60–550 nm). Besides, microfluidic strategies for hydrophilic and hydrophobic fluorescent polymer microparticles (20–800 µm) have been performed for systematic tuning in size and color combination. Furthermore, soft and bright particulate assemblies are enabled through interfacial interactions at the intermediate scale (600 nm–3 µm) between the nanometer and micrometer lengthscale. [ABSTRACT FROM AUTHOR]

A convenient asymmetric synthesis of methyl (2 S ,3 S ,6 R)-6-(4-fluorophenyl)-2-(4-hydroxyphenyl)-piperidine-3-carboxylate is described, starting from Baylis–Hillman adducts. The route involves a domino process: allylic acetate rearrangement, stereoselective Ireland–Claisen rearrangement and asymmetric Michael addition, which provides a δ-amino acid derivative with full stereochemical control. A subsequent chemoselective transformation of one of the side-chain groups allows an effective cyclization leading to biologically interesting polysubstituted piperidines in which the 2,6-aryl groups could be attached sequentially. [ABSTRACT FROM AUTHOR]