Structural study of a novel acetylide-thiourea derivative and its evaluation as a detector of benzene

Assessment on functionalized conjugated acetylide and its designated acetylide-imine moieties towards Acanthamoeba sp.: An in vitro bioindicator study

The demand for developing bioindicators to assess environmental pollution has increased significantly due to the awareness of potential threats of diseases. Herein, the eukaryotic ubiquitous microorganism Acanthamoeba sp. was used as a bioindicator to explore further the influence of functionalized organic molecules containing -CC- and -CHN- moieties prior application in the potential electronic components. The acetylide and hybrid acetylide-imine derivatives (FYD3A, FYD4B, and FYD4C) were tested for their cytotoxicity potentials based on dose-response analysis, morphological observation, and mode of cell death assessment on Acanthamoeba sp. (environmental-isolate). The biological activities of optimized compounds were evaluated by HOMO-LUMO energy gap and MEP analysis. The determination of the IC50 value through the MTT assay showed functionalized organic molecules of FYD3A, FYD4B, and FYD4C, revealing the inhibition growth of Acanthamoeba sp. with IC50 values in the 3.515-3.845 μg/mL range. Morphological observation displayed encystment with cellular agglutination and overall cell shrinkage. AO/PI-stained moieties-treated Acanthamoeba sp. cells appeared with shades of red to orange in necrotic Acanthamoeba cells whilst green to yellow apoptotic Acanthamoeba cells when compared to entirely green fluorescence untreated cells. Moreover, the results of the mitochondrial membrane potential (MMP) assay demonstrate the integrity and functionality potential of the mitochondrial membrane in cells, where a decrease in the MMP assay is linked to apoptosis. This study confirmed that the functionalized organic molecule featuring acetylide and its designated acetylide-imine moieties exhibit cytotoxicity towards the Acanthamoeba sp. by apoptotic and necrotic mode of cell death. This indicates that seeping these derivatives as electronic components can lead to the leaching of hazardous chemicals and contribute to environmental pollution that negatively affects the ecosystem. This study proposes the selection of efficient systems and elements for functionalized organic molecules that are safe to be released into the environment.

Exploring ethynyl-based chalcones as green semiconductor materials for optical limiting interests

The fabrication of molecular electronics from non-toxic functional materials which eventually would potentially able to degrade or being breaking down into safe by-products have attracted much interests in recent years. Hence, in this study, the introduction of mixed highly functional substructures of chalcone (-CO-CH=CH-) and ethynylated (C≡C) as building blocks has shown ideal performance as solution-processed thin film candidatures. Two types of derivatives, (MM-3a) and (MM-3b) repectively, showed a substantial Stokes shifts at 75 nm and 116 nm, in which such emission exhibits an intramolecular charge transfer (ICT) state and fluoresce characteristics. The density functional theory (DFT) simulation shows that MM-3a and MM-3b exhibit low energy gaps of 3.70 eV and 2.81 eV, respectively. TD-DFT computations for molecular electrostatic potential (MEP) and frontier molecular orbitals (FMO) were also used to emphasise the structure-property relationship. A solution-processed thin film with a single layer of ITO/PEDOT:PSS/MM-3a-MM-3b/Au exhibited electroluminescence behaviour with orange and purple emissions when supplied with direct current (DC) voltages. To promote the safer application of the derivatives formed, ethynylated chalcone materials underwent toxicity studies toward Acanthamoeba sp. to determine their suitability as non-toxic molecules prior to the determination as safer materials in optical limiting interests. From the preliminary test, no IC50 value was obtained for both compounds via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay analysis and molecular docking analysis between MM-3a and MM-3b, with profilin protein exhibited weak bond interactions and attaining huge interaction distances.

Benzoyl isothiocyanate modified surface of silica gel as the extraction material for adsorbing steroid hormones in water

Steroid hormones have been listed as priority pollutants in the environment, and their detection and pollution control deserve our extensive attention. In this study, a modified silica gel adsorbent material was synthesized by benzoyl isothiocyanate reaction with hydroxyl groups on the silica gel surface. The modified silica gel was used as a solid phase extraction filler for the extraction of steroid hormones from water, which was further analyzed by the HPLC-MS/MS method. The FT-IR, TGA, XPS, and SEM analysis indicated that benzoyl isothiocyanate was successfully grafted on the surface of silica gel to form a bond with an isothioamide group and benzene ring as the tail chain. The modified silica gel synthesized at 40 °C showed excellent adsorption and recovery rates for three steroid hormones in water. Methanol at pH 9.0 was selected as the optimal eluent. The adsorption capacity of the modified silica gel for epiandrosterone, progesterone, and megestrol acetate was 6822 ng mg^-1, 13 899 ng mg^-1, and 14 301 ng mg^-1, respectively. Under optimal conditions, the limit of detection (LOD) and limit of quantification (LOQ) for 3 steroid hormones by modified silica gel extraction with HPLC-MS/MS detection were 0.02-0.88 μg L^-1 and 0.06-2.22 μg L^-1, respectively. The recovery rate of epiandrosterone, progesterone, and megestrol was between 53.7% and 82.9%, respectively. The modified silica gel has been successfully used to analyze steroid hormones in wastewater and surface water.

A Dual Approach on Experimental, Theoretical Insight of Structural Elucidation, Hirshfeld Surface Analysis, Optical and Electrochemical Properties of Acyl Thiourea-Ethynyl Hybrid Derivatives

Hybrid moieties of ethynylated-thiourea, Th1 and Th2 have been synthesised via the addition reaction between ethynyl derivatives and 4-tert-butylbenzoyl isothiocyanate in acetone, and were characterised by selected spectroscopic methods (i.e., ¹H and ¹³C NMR, UV-visible, FT-IR) and elemental analysis. Thermogravimetric analysis indicated that Th1 and Th2 were relatively stable up to ca. 210 °C. Single-crystal X-ray diffraction was used to identify the crystal structure of Th2 in which the centre of 1-acyl thiourea moiety (-C(O)NHC(S)NH) exhibits S conformation. The Hirshfeld surface analysis has allowed visualizing the crystal packing, which is characterised by the prolonged intermolecular N-H⋯O = C and N-H⋯S = C hydrogen-bonding interactions within Th2 molecule. Electrochemical data of both compounds correspondingly exhibit irreversible redox potential processes. Besides, frontier molecular orbitals and Natural Bond Orbital population analysis were computed at the B3LYP/6-31G (d, p) level of approximation, suggesting strong delocalization of the electronic density through a conjugated π-system involving the ethynyl-phenyl and thiourea groups.

GRAPHICAL ABSTRACT

Figure of molecular structure for acyl thiourea-ethynyl derivative. Two derivatives of acyl thiourea-ethynyl were synthesised and characterised by selected spectroscopic methods such as 1H and 13C NMR, UV-visible, FT-IR, elemental, thermal, electrochemical, X-ray diffraction, and density functional theory (DFT) calculation for molecular orbitals and natural bond orbital population analysis.

Effect of pH on functional, gas sensing and antimicrobial properties of bio-nanocomposite gelatin film for food packaging application

A bio-nanocomposite film is a polymer blend with nanofiller dispersed in a biopolymer matrix. The aim of this study is to investigate the functional, gas sensing and antimicrobial properties of bio-nanocomposite films incorporated with chicken skin gelatin/ tapioca starch/zinc oxide at different pH levels (pH 4, 6, 7 and 8). Bio-nanocomposite films were prepared using a casting technique followed by the characterization of their functional, gas sensing and antimicrobial properties. Film formulations with pH at different levels showed increased thickness, colour and water vapour permeability (WVP) (p < 0.05). In addition, the increase of pH in films in chicken skin gelatin bio-nanocomposite films increased the tensile strength (TS), while decreasing the elongation at break (EAB). The highest response for ammonia gas in chicken skin gelatin bio-nanocomposite films was obtained at pH 7, with quick response time (τres) within 10 s. The inhibition zone of Staphylococcus aureus in chicken skin gelatin bio-nanocomposite films increased with increasing pH levels. Overall, chicken skin gelatin bio-nanocomposite films with a pH level of 8 were found to have the optimal formulation, with the highest values in thickness, and TS, with the lowest values for WVP and EAB. In conclusion, bio-nanocomposite chicken skin gelatin films with an alkaline pH are a superior packaging material.

Synthesis of New Highly Functionalized 1H-Indole-2-carbonitriles via Cross-Coupling Reactions

An approach for the preparation of polysubstituted indole-2-carbonitriles through a cross-coupling reaction of compounds 1-(but-2-ynyl)-1H-indole-2-carbonitriles and 1-benzyl-3-iodo-1H-indole-2-carbonitriles is described. The reactivity of indole derivatives with iodine at position 3 was studied using cross-coupling reactions. The Sonogashira, Suzuki–Miyaura, Stille and Heck cross-couplings afforded a variety of di-, tri- and tetra-substituted indole-2-carbonitriles.

Room-Temperature Benzene Sensing with Au-Doped ZnO Nanorods/Exfoliated WSe2 Nanosheets and Density Functional Theory Simulations

A gold-doped zinc oxide (Au-ZnO)/exfoliated tungsten diselenide (exfoliated WSe₂) nanocomposite-based gas sensor toward benzene with high sensing properties was demonstrated. Epoxy resin was used as the matrix of the Au-ZnO/exfoliated WSe₂ nanocomposite sensor. The straw-shaped Au-ZnO was synthesized by the hydrothermal method, and WSe₂ nanosheets (NSs) were prepared via hydrothermal and liquid-phase exfoliation methods. The properties of Au-ZnO/exfoliated WSe₂ nanoheterostructures constructed by self-assembly technology have been confirmed via a series of characterization methods. The benzene-sensing performances of sensors were tested at 25 °C. Compared with Au-ZnO, WSe_2, and their composites, the Au-ZnO/exfoliated WSe₂ sensor has a significant performance improvement, including a higher response and linear fit degree, better selectivity and repeatability, and faster detection rate. The significantly enhanced sensing properties of the Au-ZnO/exfoliated WSe₂ sensor can be ascribed to the doping of Au nanoparticles, the increase in the specific surface area and adsorption sites of NSs after exfoliation, and the cooperative interface combination of the ZnO/WSe₂ heterojunction. Furthermore, the sensitivity mechanism of the composite sensor to benzene was explored by density functional theory simulations.

Design, Synthesis, and Docking Study of Acyl Thiourea Derivatives as Possible Histone Deacetylase Inhibitors with a Novel Zinc Binding Group

Histone deacetylase inhibitors with zinc binding groups often exhibit drawbacks like non-selectivity or toxic effects. Thus, there are continuous efforts to modify the currently available inhibitors or to discover new derivatives to overcome these problems. One approach is to synthesize new compounds with novel zinc binding groups. The present study describes the utilization of acyl thiourea functionality, known to possess the ability to complex with metals, to be a novel zinc binding group incorporated into the designed histone deacetylase inhibitors. N-adipoyl monoanilide thiourea (4) and N-pimeloyl monoanilide thiourea (5) have been synthesized and characterized successfully. They showed inhibition of growth of human colon adenocarcinoma and mouse hepatoblastoma cells with low cytotoxic effect against normal human breast cells. Their binding mode to the active site of several histone deacetylases has been studied by docking and the results gave a preliminary indication that they could be successful histone deacetylase inhibitors.

Hierarchical Nanoheterostructure of Tungsten Disulfide Nanoflowers Doped with Zinc Oxide Hollow Spheres: Benzene Gas Sensing Properties and First-Principles Study

This paper reports an original fabrication of a benzene gas sensor based on tungsten disulfide nanoflowers (WS₂ NFs)/zinc oxide hollow spheres (ZnO HMDs) hierarchical nanoheterostructure. The ZnO/WS₂ hierarchical composite was characterized for the inspection of its nanostructure, elementary composition, and surface morphology. The benzene-sensing properties of the ZnO/WS₂ nanofilm sensor were exactly investigated. The results illustrate that the ZnO/WS₂ sensor exhibits a remarkable sensing performance toward benzene gas, including good sensitivity, rapid detection, outstanding repeatability, and stability. This is attributed to the fact that the ZnO/WS₂ nanoheterostructure can dramatically enhance the benzene sensing performance. Furthermore, density functional theory was employed to construct the benzene gas adsorption model for the ZnO/WS₂ heterostructure, from which the determined parameters in geometry, energy, and charge provided a powerful support for the mechanism explanation. This work suggests that the ZnO/WS₂ nanoheterostructure is competent to detect trace benzene gas at room temperature.

Crystal structure of bis(2-((allylcarbamothioyl)imino)-4-methylthiazol-3-ido-κ2 N,S)palladium(II), C16H20N6PdS4

C16H20N6PdS4, monoclinic, C2/c (no. 15), a = 13.2801(8) Å, b = 18.5771(8) Å, c = 10.2577(5) Å, β = 121.906(2)°, V = 2148.29(19) Å3, Z = 4, R gt(F) = 0.0300, WR ref(F 2) = 0.0721, T = 293 K.