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The urease enzyme is recognized as a valuable therapeutic agent for treating the virulent Helicobacter pylori bacterium because of its pivotal role in aiding the colonization and growth of the bacterium within the gastric mucosa. In order to control the harmful consequences of bacterial infections, urease inhibition presents itself as a promising and effective approach. The current research aimed to synthesize pyridylpiperazine-based carbodithioate derivatives 5a-5n and 7a-7n that could serve as potential drug candidates for preventing bacterial infections through urease inhibition. The synthesized carbodithioate derivatives 5a-5n and 7a-7n were explored to assess their ability to inhibit the urease enzyme after their structural explication by gas chromatography-mass spectrometry (GC-MS). In the in vitro evaluation with thiourea as a standard drug, it was observed that all the synthesized compounds exhibited significant inhibitory activity compared to the reference drug. Among the compounds tested, 5j (bearing an o-tolyl moiety) emerged as the most effective inhibitor, displaying strong urease inhibition with an IC50 value of 5.16 ± 2.68 pM. This IC50 value is notably lower than that of thiourea (23 ± 0.03 pM), indicating the significantly most potent potential of inhibition. In molecular docking of 5j within the active site of urease, numerous noteworthy interactions were identified. [ABSTRACT FROM AUTHOR]

New PVC/ABS and CoCl2 composites with various concentrations of cobalt chloride (≤10 wt. %) were synthesized by solution casting techniques and investigated by spectro-chemical, morphological and thermal mode of characterization. The FT-IR, XRD and SEM analyses proved the smooth distribution and uniformity of the constituents of the composite materials. Thermal behavior showed that the addition of CoCl2 to the PVC/ABS blends enhanced the thermal stability and improved mechanical properties of composites due to crosslinking between PVC/ABS blend and CoCl2. Thus based on their remarkable morphology, thermomechanical stability and promising bioactivities, the synthesized composites could be applied for high performance polymeric materials in the field of biomedics and electronics.

Halloysite nanotubes (HNTs) reinforced epoxy composites with improved mechanical properties were prepared. The prepared HNTs reinforced epoxy composites demonstrated improved mechanical properties especially the fracture toughness and flexural strength. The flexural modulus of nanocomposite with 6% mHNTs loading was 11.8% higher than that of neat epoxy resin. In addition, the nanocomposites showed improved dimensional stability. The prepared halloysite reinforced epoxy composites were characterized by thermal gravimetric analysis (TGA). The improved properties are attributed to the unique characteristics of HNTs, uniform dispersion of reinforcement and interfacial coupling.

A simple, rapid and sensitive spectrophotometric method for the assay of clomipramine--HCl is described. It has been found that clomipramine--HCl reacts with ammonium molybdate in acetic medium to give blue color product exhibiting maximum absorbance at 712 nm. The reaction is selective for clomipramine--HCl with 1 ng/mL as visual limit of detection. It provides a basis for a sensitive spectrophotometric method for the determination of clomipramine--HCl. The method obeys Beer's Law from 0.001 to 0.250 mg/mL. The standard deviation does not exceed 0.005 mg/mL. The method has been successfully applied to the determination of clomipramine--HCl in pure form and pharmaceutical preparations. The quantitative assessment of tolerable amounts of possible interferants was also studied. The results are reproduced within ±1% and are in good agreement with those obtained by the standard procedure. Keywords: clomipramine--HCl, spectrophotometric analysis DOI: 10.1134/S1061934814060136, Clomipramine hydrochloride is the generic name of 3-chloro-10,11-dihydro-N,N-dimethyl5H-dibenz[b,f]azepine-5-propanamine hydrochloride: [FORMULA NOT REPRODUCIBLE IN ASCII] It is a white to off-white powder, very soluble in water. Its action and uses are [...]

This study focuses on the experimental and molecular-level investigation of epoxy acrylate formation. Epoxy acrylate vinyl ester resin was prepared by a reaction of diglycidyl ether of bisphenol-A-based epoxy resin and acrylic acid, using benzimidazole as a catalyst. It was confirmed that benzimidazole can effectively catalyze this reaction. FTIR analysis of the product revealed a simple addition esterification reaction between the epoxide group and carboxylic group of acrylic acid excluding the side reactions (e.g., etherification). DFT computational studies were performed to theoretically explore the insights of reaction mechanisms. The calculations revealed that the benzimidazole-catalyzed reaction dominates the uncatalyzed reaction. A comparison of calculated activation energies showed that concerted mechanisms are less significant in such reactions owing to their high activation barriers. [ABSTRACT FROM AUTHOR]

A series of D‐π‐A type molecules have been designed for their potential use in organic photovoltaic devices. Photovoltaic and optoelectronic properties of newly designed molecules have been explored by comparing with a reference molecule R comprising of the central core (2,3,8,9‐tetrakis(thiophen‐2‐ylethynyl)‐5,7,10,12‐tetrakis((trimethylsilyl)ethynyl)pyrazino[2,3‐b]phenazine) and π‐bridge (thiophene). The end groups are (2‐(2‐ethylidene‐3‐oxo‐2,3‐dihydro‐1H‐inden‐1 ylidene)malononitrile), (2‐ethylidenemalonitrile), (methyl 2‐cyanoacrylate) and (3‐methyl‐5‐methylene‐2‐thioxothiazolidin‐4‐one) in the newly designed molecules. Among the investigated molecules M1 and M2 exhibit a broad absorption range of 627 and 626 nm with respect to the reference. All the designed molecules exhibited a lower bandgap as compared to R which indicates a better transfer of electron density from highest occupied molecular orbital (HOMO) to lowest unoccupied molecular orbital (LUMO). The reorganization energy values show that all designed molecules have efficient charge transport capability. This study proves that end‐capped acceptor modification is an effective strategy for designing optimistic molecule for high performance future organic solar cells fabrication. [ABSTRACT FROM AUTHOR]

The PMMA/PVC/ZnO-nanocomposites with zinc oxide nanoparticle (particle size < 50nm) was synthesized by solution casting technique. Morphology of the synthesized nano composites have been investigated by FT-IR and XRD techniques. After characterization, synthesized composites were applied for antibacterial, selective antibiofilm and free radical scavenging screening. Antibacterial studies were measured against different bacterial strains. Antibiofilms activities were studied against those bacterial model pathogenic strains which showed highest and minimum sensitivity as a (~94 and ~88 at 160 µg/ml). Antioxidant activity of synthesized nanocomposites were measured by DPPH and showed scavenging capacity with IC50, 110 to > 200 µg/mL. Thus PMMA/PVC/ZnO nanocomposite showed promising antimicrobial activity and antioxidant activity that can be used for biomedical applications. [ABSTRACT FROM AUTHOR]

Degree based topological indices are being widely used in computer-aided modeling, structural activity relations, and drug designing to predict the underlying topological properties of networks and graphs. In this work, we compute the certain important degree based topological indices like Randic index, sum connectivity index, ABC index, ABC4 index, GA5 index and GA index of Book graph Bn and Stacked book graph Bm,n. The results are analyzed by using edge partition, and the general formulas are derived for the above-mentioned families of graphs. [ABSTRACT FROM AUTHOR]

Hybrid materials based on polyaniline derivative and metal nanofiller were reported for potential antibacterial applications. Polyorthochloroaniline/copper nanocomposites (POC/Cu NCs) were synthesized by in situ chemical oxidative polymerization of orthochloroaniline using ammonium persulfate as oxidant, in the presence of copper nanoparticles (CuNPs) and 4,4′‐diaminodiphenylamine. CuNPs were prepared through reduction of copper chloride by using sodium borohydride as reducing agent. The composition, structure, and morphology of CuNPs, POC, and their composites were characterized by UV–visible spectroscopy, Fourier transform infrared spectrometry, X‐ray diffractometry, and scanning electron microscopic techniques. The antibacterial potential of nanocomposites against gram‐positive bacteria (Bacillus subtilis) and gram‐negative bacteria (Escherichia coli) for various loads of copper nanofiller was evaluated using viable cell counts. The outcomes showed that nanocomposites have better antimicrobial efficacy than POC under the similar testing conditions. The mechanism of the synergistic antimicrobial effect of POC/Cu NCs was also proposed. POLYM. COMPOS., 39:4524–4531, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]