An iron-catalyzed [4 + 2] cyclization for constructing 4-Arylpyrimido[1,2-b] indazoles using 3-Aminopyrazole, phenylacetylene and N, N-Dimethylformamide has been reported, where N, N-Dimethylformamide (DMF) acted one-carbon synthon. The reaction conditions are mild and rapid, with a wide range of applicable substrates.

An I2-DMSO-mediated, one-pot synthesis of 1-(1H-indazol-3-yl)-2,4-diphenyl-1H-pyrrolo[2',3':4,5]pyrimido[1,2-b]indazole derivatives using 3-aminoindazoles, acetophenones, and enaminones as starting materials has been developed. The key to realizing this process lies in the multiple trapping of the in situ generated ketenimine cation by the two molecules of 3-aminoindazole. The structure of the compound was determined through X-ray single-crystal experiments, and the study expanded to include 40 compounds. Spectroscopic studies showed that the selected compounds have maximum absorption at 443-490 nm and maximum emission at 543-574 nm with quantum yields of 0.07-0.24.

An I2-DMSO-mediated, one-pot synthesis of benzo[4,5]imidazo[1,2-a]pyrimidine-2,3-diylbis(phenylmethyl ketone) derivatives have been developed using 2-aminobenzimidazole, acetophenone, and enaminone as starting materials. The structures of the compounds were characterized by single-crystal X-ray diffraction.

A novel and efficient synthesis of 2,4-disubstituted benzo[4,5]imidazo[1,2-a]pyrimidine skeletons is reported. Using 2-aminobenzimidazole and acetophenone as substrates, an I2-DMSO-mediated multicomponent reaction was described, which used a one-pot method to generate two C-N bonds and one C-C bond, yielding 25 substrates. Currently, such derivatives are used clinically for biorevealing, so we selected some of the compounds in this paper for photophysical characterization. Spectroscopic studies showed that the selected compounds have maximum absorption at 250 nm and maximum emission at 600 nm with quantum yields of 0.01-0.08.

A simple and efficient method for the synthesis of symmetric 2,3,5,6-tetrasubstituted pyridines from enaminones and triethyl orthoformate, catalyzed by pyridinium p-toluenesulfonate, has been established in which triethyl orthoformate was applied as a carbon source. The procedure was smoothly executed, culminating in the synthesis of symmetrical 2,3,5,6-tetrasubstituted pyridines with moderate to exceptional yields across a diverse array of substrates.

In this article, the radical scavenging performance of eight anti-agers ( TMQ , ETMQ , DCD , o-MBp24 , o-MBp14 , p-BBp14 , DNPD , and 6PPD ) was benchmarked by the experimental residue rates of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, followed by the theoretical investigation from the perspective of both kinetic and thermodynamic factors. Kinetically, anti-agers with lower Gibbs free energy barriers ( Delta G / = ) presumably exhibit higher scavenging performance. Moreover, the scavenging performance is also controlled by the thermodynamic feature, that is, the small difference in Gibbs free energy between products and reactants ( Delta G (R -> P)) promotes the scavenging performance. Therefore, the Delta G / = x Delta G (R -> P) indicator considering both kinetic and thermodynamic contributions was proposed here to comprehensively explain the difference in the scavenging performance of anti-agers. The strong positive correlation between experimental residues and Delta G / = x Delta G (R -> P) values (R 2 = 0.806) revealed that the Delta G /= x Delta G (R -> P) indicator promises to be a reliable metric to theoretically assess the scavenging performance of antiagers.

A simple and efficient method for the synthesis of 1,4-dihydropyridines from amines, N,N-dimethyl enaminone and N,N-dimethylaminoethanol in a four-component [2+1+2+1] annulation catalyzed by FeCl3 has been established, where N,N-dimethylaminoethanol was applied as a methine source. The procedure was executed smoothly, resulting in the synthesis of a wide range of 1,4-dihydropyridines with moderate to good yields. Additionally, these fluorophores exhibited good photophysical characteristics.

As a novel and environmentally friendly Brönsted acid, imidazole hydrochloride was used to promote the synthesis of 2,3-disubstituted-4(3H)-quinazolinone from o-aminobenzoic acid and DMF derivatives. The essence of this reaction is a multicomponent reaction, which constructs multiple chemical bonds between different components through the transamidation of imidazole hydrochloride. This protocol showed a wide range of functional group tolerance, and a series of quinazolinones were synthesized in low to moderate yields without metal catalysts, oxidants or other additives.

An efficient method for the construction of benzo[4,5]imidazo[1,2-a]pyrimidines using N,N-dimethylformamide as a one-carbon source and 2-aminobenzimidazoles and acetophenone as substrates through a one-pot, three-component cascade reaction is described. Spectra investigations indicated the fluorescent properties of selected products, exhibiting quantum yields 0.07-0.16 with maxima absorption at 266-294 nm and emission at 472-546 nm.

A simple, efficient and mild methodology for the synthesis of 1,3,2-benzodiazaborininones [R-B(aam)] from boronic acids and anthranilamides on ethyl acetate is described. A series of 1,3,2-benzodiazaborininones were prepared in moderate to excellent yields at room temperature without dehydrating agents, metal catalysts, corrosive acids or other additives. Meanwhile, a multi-gram scale reaction is also performed to ensure the scalability of the reaction, and the product can be conveniently isolated by simple filtration.

An efficient approach to 1H-perimidines synthesis from 1,8-diaminonaphthalene reactions with alpha-keto acids was described. The reaction was conducted under metal-free and additive-free conditions, using EtOH as a solvent. Moreover, this reaction can be conducted on a gram-scale, and shows a wide range of functional group tolerance.

Advances in immune checkpoint inhibitors (ICIs) have enabled more effective treatment for individuals with various types of solid tumors. Given the improved survival benefit and acceptable safety profile of ICIs in advanced gastric cancer, there is plenty of interest in the use of ICIs in the neoadjuvant setting with curative intent. Theoretically, immunoneoadjuvant with ICIs could boost the levels of endogenous tumor antigen present in the tumor to enhance T-cell priming and further enhance systemic immunity. This systemic immune response may improve the detection and elimination of the disseminated micrometastatic tumors beyond the resected tumor, which are sources of postsurgical relapse. Numerous clinical studies have begun to explore the application of ICIs in neoadjuvant treatment of gastric cancer. This article reviews the progress in the use of ICI monotherapy and in combination with alternative therapies for the treatment of gastric cancer to aid in the development of gastric cancer immunoneoadjuvant therapy and improve the overall therapeutic benefit.

An efficient and practical approach for the synthesis of tetrasubstituted pyridines has been described via the Imidazole hydrochloride-promoted reaction of enaminones with DMSO. This protocol showed good functional group tolerance, and a series of pyridines were synthesized in moderate to good yields without metal catalysts. A multi-gram scale reaction was also performed to ensure the scalability of the reaction. Notably, DMSO plays two vital roles: carbon source and solvent.

Si69 and Si75, typical commodities of silane coupling agents, are often employed in tire recipes to work as the bridges connecting silica and polymers, with which rolling resistance and wet traction are enhanced without loss in abrasion resistance. In this article, the reactivities of Si69 and Si75 with silica and various rubbers were theoretically investigated by using density functional theory (DFT). When the agents were coupled with silica, not only the acid+water condition but also the pure acid condition was confirmed to readily trigger the condensation reactions. The corresponding Gibbs free energy barriers were related to the charge distributions of reaction regions. As the agents suffered from the homolysis of central SS bonds, the generated single-S-tailer radicals (RS·) showed significantly higher reactivities of both the radical addition and the α-H transfer reactions with rubbers, due to the stronger radical philicities of the terminal sulfur radicals with larger condensed local softnesses [s0 (S)]. When the agents underwent the heterolysis of central SS bonds, the terminal sulfur anions with smaller s- (S) indices, however, facilitated the nucleophilic addition reactions with rubbers. Several derivative indices based on the condensed local softnesses were also proposed here to shed light on the reactivities from the viewpoint of the relationship between energy barriers and electronic characteristics. The above findings pave the way for the design of new kinds of silane coupling agents using computer-aided techniques, and meanwhile, provide references for the practical application of Si69 and Si75 to the silica/rubbers systems.

Imidazole hydrochloride, a hydrochloric acid carrier, was used to mediate the decarboxylation of orthopara position amino-substituted aromatic acids and nitrogen-containing heterocyclic acids, which gave excellent yields within a short time. In addition, the method can be well adapted to a gram scale, and the imidazole hydrochloride additives can be appropriately recovered for secondary utilization. (c) 2022 Elsevier Ltd. All rights reserved.

Background and Objective: As a key pharmacophore, the cyano group widely exists in a variety of biologically active compounds. Besides, nitriles are also valuable intermediates for many common functional groups. In this current work, a new synthesis strategy was developed to obtain nitriles from aldehydes. Methods: Using commercially available aldehydes as raw materials, and hydroxylamine and hydrochloride as nitrogen sources, the corresponding nitrile compounds were successfully synthesized by the one-pot method through the promotion of imidazole hydrochloride. And it was characterized by 1H NMR, 13C NMR, and mass spectrometry. Results: Various reaction conditions were applied in order to find an optimum and convenient procedure for the formation of nitriles. The highest yields (95%) were achieved using sulfolane as a solvent, and imidazole hydrochloride as a promoter. Conclusion: In conclusion, we developed a new synthetic method for nitrile compounds from aldehydes. Twenty seven examples of functionalized nitrile compounds have been synthesized in good to excellent yields. This methodology features that an environmentally benign imidazole hydrochloride replaces transition metal catalysts and oxidants required in conventional strategies to convert aldehydes into nitriles with good functional group tolerability. Further exploration of imidazole hydrochloride is ongoing in our laboratory.

This article reports an efficient method for the synthesis of amide derivatives by the direct reactions of aromatic amines with 1,3-diketones promoted by pyridine hydrochloride under metal-free and solvent-free conditions. This transformation was accomplished by cleavage of CC bond in the presence of pyridine hydrochloride as additive, which excludes the use of transition-metals and harsh reaction conditions. This method has a broad substrate scope and good tolerance for sensitive functional groups. A multi-gram scale reaction is also performed to ensure the scalability of the reaction.

A facile universal and economical method for the synthesis of perimidine has been described via the imidazolium chloride-promoted cyclizaton of 1,8-diaminonaphthalene with N,N-dimethylformamide (DMF) derivatives. This protocol showed a wide range of functional group tolerance, and a series of perimidines were synthesized in moderate to excellent yields without metal catalysts, solvent or other additives. A multi-gram scale reaction is also performed to ensure the scalability of the reaction.

A green and efficient method for the synthesis of oxadiazaborole, dioxazaborinine, and oxadiazaborinine from the reactions of phenylboronic acid with amidoxime, α-hydroxyl oxime and α-hydroxyl hydrazone, respectively, is described. The reactions were performed under catalyst-free and mild conditions. All products can be rapidly purified by filtration and washing. In addition, a set of iminoboronates were prepared following a one-pot multicomponent reaction procedure using α-hydroxyl hydrazone, salicylaldehyde and boronic acid derivatives as starting materials and their photophysical properties were assessed. Then, cross-coupling reactions can be carried out smoothly on some target compounds, which may help develop new boron masking strategies.

An environment-friendly methodology for the synthesis of R (alkyl or aryl)-B(dan) on water is described. 1,8-diamino naphthalene(danH2) was reacted with different types of organoboronic acids to furnish the products in moderate to excellent yields. A multi-gram scale reaction is also performed to ensure the scalability of the reaction.