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The Cu-catalysed azide-alkyne cycloaddition (CuAAC) reaction, also known as the "click" reaction, is a powerful tool in organic synthesis due to its high efficiency, regioselectivity, and mild reaction conditions. However, the use of homogeneous copper catalysts often leads to challenges like separation and disposal, limiting their applicability in industrial settings. This study aimed to develop a novel heterogeneous catalyst utilizing NiO/Cu2O/CuO nanocomposites (NCs) for the selective and efficient synthesis of 1,4-disubstituted-1,2,3-triazoles via the click reaction. NiO/Cu2O/CuO NCs were prepared by a simple co-precipitation method. The catalytic activity of the prepared NCs was evaluated for the one-pot, three-component click reaction between benzyl bromide analogues, sodium azide, and phenyl acetylene under various conditions: ambient temperature, thermal heating, and microwave irradiation. The reaction progress was monitored by TLC, and the products were isolated and characterized by SEM, FTIR, XRD, and XPS. The NiO/Cu2O/CuO NCs exhibited superior catalytic performance compared to Cu2O/CuO nanoparticles (NPs). They facilitated the exclusive formation of the desired 1,4-isomer under all tested conditions. Notably, under microwave irradiation, the NiO/Cu2O/CuO NCs delivered significantly higher yields (89–96%) compared to Cu2O/CuO NPs (76–82%) for diverse triazole compounds. Characterization confirmed the successful synthesis of the NCs and the purity of the triazole products. Utilizing water as the solvent under microwave irradiation offered several advantages, including faster reaction rates, higher yields, efficient product isolation, and excellent recyclability of the catalyst. This study demonstrates the effectiveness of NiO/Cu2O/CuO NCs as a novel heterogeneous catalyst for the selective and efficient synthesis of 1,4-disubstituted-1,2,3-triazoles. The simple and efficient method, coupled with the advantages of water as a solvent and microwave-assisted heating, presents significant potential for various applications in organic synthesis and beyond. [ABSTRACT FROM AUTHOR]

In this study, the hydrolysis of TiCl4 was utilized to synthesize titanium dioxide clusters (TiO2 NCs) at a sub-nanometer scale. Precise control over the synthesis process resulted in the production of stable particles with well-defined size distributions. These TiO2 NCs were specifically developed to facilitate the conversion of SOx into organo-sulfonic acid derivatives under visible light irradiation. Various characterization techniques such as TEM, EDX, XRD, UV–Vis-DRS, Raman, and FTIR were employed to analyze the formed photocatalysts, including TiO2 nanoparticles (NPs) and NCs. The efficiency of catalytic SOx removal depended significantly on the particle size and surface area of the nanocatalysts, as well as the presence of thymol or naphthol (1,2). These materials (1,2) proved to be highly effective in removing SOx from flue gas under ambient conditions, specifically at room temperature. The conversion of thymol or naphthol involved a combination of adsorption and catalytic oxidation–reduction reactions. This photocatalytic approach for SOx conversion offers several advantages, including high performance, elimination of the need for high temperature or pressure, and rapid catalytic removal within a short reaction time of 10 min. TiO2 NCs demonstrate high efficiency in SOx removal, offering a promising solution for pollution control. Unlike some other methods, TiO2 nanoparticles can be potentially regenerated and reused, making them a more sustainable approach. [ABSTRACT FROM AUTHOR]

Heterocyclic pyridazine continues to attract great interest, mainly arising from a large variety of interesting pharmacological activities, herbicides, insecticides, and fungicides. On the other hand, the current interest in selenium-containing heterocycles is a result of their chemical properties and biological activities. In addition to the many recent publications dealing with the pharmacological potential of a selenium compound, new active formulations are an attractive target for chemical research. 2-((3-cyano-4,6-dimethylpyridin-2-yl)selanyl) acetic acid (pyd-Se), 2-((4-cyano-5,6-diphenylpyridazin-3-yl)selanyl)acetic acid (pydz-Se) and 2-((4,6-dimethyl quinolin-2-yl)selanyl)acetic acid (quin-Se) reacts with gold(III) chloride to produce metal ion complexes of specific composition. These synthesized complexes were characterized by elemental analyses, molar conductivity, FTIR, 1H NMR and transmission electron microscopy (TEM) investigations. The complexes were found to have the formulas [Au(pyd-Se)2]Cl, [Au(pydz-Se)2]Cl and Au(quin-Se)2]Cl, respectively. [ABSTRACT FROM AUTHOR]

Both 2‐(N‐arylcarbamoyl)methylsulfanyl‐3‐cyano‐5‐ethoxycarbonyl‐6‐methyl‐4‐(2′‐thienyl)pyridines 2a‐e and their isomers, 3‐amino‐2‐(N‐arylcarbamoyl)‐5‐ethoxy‐carbonyl‐6‐methyl‐4‐(2′‐thienyl)thieno[2,3‐b]pyridines 3a‐e were synthesized by reaction of ethyl 3‐cyano‐1,2‐dihydro‐6‐methyl‐4‐(2′‐thienyl)‐2‐thioxopyridine‐5‐carboxylate (1) with the respective N‐aryl‐2‐chloroacetamides in the presence of different basic catalysts. Compounds 3a‐e were used as precursors for synthesizing of pyridothienopyrimidinones 4a‐e, pyridothienotriazinones 5a‐e and tetrahydropyridothienopyrimidinones 6a‐c via treatment with triethyl orthoformate, nitrous acid, and/or 4‐chlorobenzaldehyde respectively. The photophysical properties of aminothienylthienopyridines 3a‐e and tetrahydropyridothieno‐pyrimidine‐4(3H)‐ones 6a‐c were studied and the fluorescence data revealed that all selected compounds possess AIE behaviors in solution and in solid state. Most of the prepared compounds were evaluated in vitro for their antibacterial and antifungal activities, and considerable results were obtained. Moreover, the cytotoxic activity of thienopyridines 3a‐d against MCF‐7 and HepG2 cell lines was evaluated and they showed moderate to very strong activity. [ABSTRACT FROM AUTHOR]

5‐Acetyl‐3‐cyano‐6‐methyl‐4‐(2‐phenylethenyl)pyridine‐2(1H)‐thione (2) was synthesized by interaction of cinnamylidene‐2‐cyanothioacetamide 1 and acetylacetone or via one‐pot reaction of E‐cinnamaldehyde, 2‐cyanothioacetamide, and acetylacetone. Reaction of 2 with ethyl iodide (3a) or N‐chloroacetyl derivative of aromatic amines 3b–e in boiling ethanol containing sodium ethoxide gave the corresponding thioether 4a and 5‐acetyl‐3‐amino‐2‐(N‐arylcarbamoyl)‐6‐methyl‐4‐(2‐phenylethenyl)thieno[2,3‐b]pyridines 5b–e, respectively. Compound 5e was reacted with 2,5‐dimethoxytetrahydrofuran or triethyl orthoformate to furnish pyrrolylthienopyyridine 6 or pyrdiothienopyrimidinone 7, respectively. The photophysical properties of 5b, 5c, 5e, and 7 were fully studied and the obtained results included herein. The fluorescence data confirmed that compounds 5b, 5c, 5e, and 7 exhibit aggregation‐induced emission behavior with high absolute quantum yields. [ABSTRACT FROM AUTHOR]

Ethyl 5-cyano-1,6-dihydro-2-methyl-4-styryl-6-thioxonicotinate, its piperidinium pyridine-6-thiolate and 3-acetyl-5-cyano-1,6-dihydro-2-methyl-4-styryl-6-thioxopyridine were used as starting materials for synthesizing novel series of S-substituted methylthiopyridine-5-carbonitriles and thieno[2,3-b]pyridines with expected biological activity. Also, some novel thieno[2,3-c][2,7]naphthyridinones were synthesized. Moreover, 1,7-diamino-8,9-dihydro-5-methyl-8-phenyl-3H-pyrazolo[3,4-c][2,7]naphthyridine-6(7H)-one was synthesized by heating ethyl 5-cyano-1,6-dihydro-2-methyl-4-styryl-6-thioxonicotinate with hydrazine hydrate 99% under neat conditions. The obtained promising aminopyrazolo[3,4-c][2,7]naphthyridine-6(7H)-one was used as a precursor to get other novel derivatives with expected biological and medicinal importance. Structures of all new compounds were elucidated by elemental and spectral analysis. [ABSTRACT FROM AUTHOR]

The ability of microorganisms to reduce inorganic metals has launched an exciting eco-friendly approach towards developing green nanotechnology. Thus, the synthesis of metal nanoparticles through a biological approach is an important aspect of current nanotechnology. In this study, Streptomyces aizuneusis ATCC 14921 gave the small particle of silver nanoparticles (AgNPs) a size of 38.45 nm, with 1.342 optical density. AgNPs produced by Streptomyces aizuneusis were characterized by means of UV-VIS spectroscopy and transmission electron microscopy (TEM). The UV-Vis spectrum of the aqueous solution containing silver ion showed a peak between 410 to 430. Moreover, the majority of nanoparticles were found to be a spherical shape with variables between 11 to 42 nm, as seen under TEM. The purity of extracted AgNPs was investigated by energy dispersive X-ray analysis (EDXA), and the identification of the possible biomolecules responsible for the reduction of Ag+ ions by the cell filtrate was carried out by Fourier Transform Infrared spectrum (FTIR). High antimicrobial activities were observed by AgNPs at a low concentration of 0.01 ppm, however, no deleterious effect of AgNPs was observed on the development and occurrence of Drosophila melanogaster phenotype. The highest reduction in the viability of the human lung carcinoma and normal cells was attained at 0.2 AgNPs ppm. [ABSTRACT FROM AUTHOR]

The agricultural production in Punjab has increased manifold that aggravated the deficiencies of micronutrients in soils and plants. The availability of soil micronutrients in different soil orders depends upon the soil mineralogy, topography, climatic conditions and cropping sequences. Hence, to study the pedospheric variations of DTPA-extractable micronutrients, viz., zinc (Zn), iron (Fe), manganese (Mn) and copper (Cu), in three prominent soil orders of Punjab, a total of 144 depth-wise soil samples were collected from four major land-use systems (cultivated, horticulture, forest and pasture lands). The DTPA extractable micronutrients varied from 1.74–2.81, 1.83–2.82 and 1.81–2.80 for Zn; 5.3–6.8, 5.6–6.9, 4.3–6.3 for Fe; 5.1–7.8, 5.5–7.9, 5.4–7.5 for Mn; and 0.84–1.40, 0.93–1.68, 0.87–1.65 for Cu in soil orders Aridisol, Entisol and Inceptisol, respectively. The average content of DTPA-extractable micronutrients was highest under soil order Entisol followed by Inceptisol and Aridisol. The content of micronutrients showed a declining trend with increase in soil depth in all orders. Among different soil properties, the pH and EC showed significantly negative correlation, however, OC had non-significant correlation with DTPA-extractable micronutrients in soils. Therefore, it is concluded that parent material, land use systems and soil depth affected the distribution of DTPA extractable micronutrients in different soil orders. [ABSTRACT FROM AUTHOR]

In this work, a versatile compound, 4-cyano-1,6-dimethyl-8-phenyl-7,8-dihydroisoquinoline-3(2H)-thione (3) was synthesized and utilized as a starting compound for the preparaton of the title compounds. Thus, reaction of 3 with iodomethane, 2-chloroacetamide, ethyl chloroacetate, chloroacetonitrile or N-(benzthiazol-2-yl)-2-chloroacetamide by heating in ethanol containing sodium acetate, gave 3-unsubstituted or 3-substituted methylsulfanyl-7,8-dihydroisoquinoline-4-carbonitriles 4 or 6, 8, 10 and 16 respectively. The latter compounds (6, 8, 10 and 16) contain an active methylene group that adds easily to the carbonitrile group to build a thiophene ring, fused to an isoquinoline moiety, upon heating with sodium ethoxide in ethanol thus affording the corresponding 6,7-dihydrothieno[2,3-c]isoquinolines 7, 9, 11 and 17, in nearly quantitative yields. Compounds 9, 11 and 17 underwent further reactions with some reagents to give other 6,7-dihydrothieno[2,3-c]isoquinolines 12-15 and 3,4-dihydropyrimidothienoisoquinoline 18. All synthesized compounds were screened for their biological activity as bactericidal and fungicidal agents. Some of them showed promising antifungal activity. [ABSTRACT FROM AUTHOR]

Ethyl 5-cyano-1,6-dihydro-2-methyl-4-(2'-thienyl)-6-thioxonicotinate ( A ) was synthesized and reacted with ethyl chloroacetate in the presence of sodium acetate or sodium carbonate to give ethyl 5-cyano-6-((2-ethoxy-2-oxoethyl)thio)-2-methyl-4-(2'-thienyl)nicotinate ( 1a ) or its isomeric thieno[2,3- b ]pyridine 2a . 3-Aminothieno[2,3- b ]pyridine-2-carboxamide 2b was also synthesized by the reaction of A with 2-chloroacetamide. The reaction of 1a with hydrazine hydrate in boiling ethanol gave acethydrazide 3 . Heating ester 1a with hydrazine hydrate under neat conditions afforded 3-amino-1 H -pyrazolo[3,4- b ]pyridine 10 . Compounds 2b , 3, and 10 were used as precursors for synthesizing other new thieno[2,3- b ]pyridines and pyrazolo[3,4- b ]pyridines containing mainly the ethyl nicotinate scaffold. Structures of all new compounds were confirmed by elemental and spectral analyses. Most of the obtained compounds were evaluated for their insecticidal activity toward the nymphs and adults of Aphis gossypii (Glover,1887). Some compounds such as 4 , 9b, and 9c showed promising results. The effect of some sublethal concentrations, less than LC 50 , of compounds 4 , 9b, and 9c on the examined Aphis was subjected to a further study. The results demonstrated that exposure of A. gossypii nymphs to sublethal concentrations of compounds 4 , 9b, and 9c had noticeable effects on their biological parameters, i.e., nymphal instar duration, generation time, and adult longevity. The highest concentration C1 of all three compounds increased the nymphal instar duration and generation time and decreased adult longevity and vice versa.