One-pot multicomponent synthesis of indol-3-yl-hydrazinyl thiazoles as antimicrobial agents

A series of novel mono- and bis(indol-3-yl)hydrazinyl thiazole derivatives were efficiently synthesized via one-pot cyclocondensation of mono- or bis(indole-3-carbaldehyde), thiosemicarbazide, and phenacyl bromides. The structure of the products was confirmed by Fourier-transform infrared (FT-IR), ¹H nuclear magnetic resonance (NMR), and ¹³C NMR spectra. All synthesized compounds were evaluated for in vitro antibacterial activity against Gram-positive (Bacillus subtilis and Micrococcus luteus) and Gram-negative bacteria (Pseudomonas aeruginosa and Salmonella enteritis). Among the compounds screened, a few were found to be highly effective antibacterial agents. The bis-compounds with OCH₃ donating group exhibited good activity against the Gram-positive bacteria.     

Synthesis and photochromic behavior of mono-, and biphotochromic system linked by p-phenylene bridge

<正>The synthesis of mono- and bis-l,3-diazabicyclo[3.1.0]hex-3-ene derivatives with indole ring and p-phenylene spacer,which behave as photochromic materials,is reported.The structure-photochromic behavior relationship(SPBR) of the synthesized compounds has been analyzed.     

Adsorption of acid red 114 and reactive black 5 in aqueous solutions on dendrimer‐conjugated magnetic nanoparticles

The adsorption of the dyes Acid Red 114 and Reactive Black 5 in aqueous solutions on polyhydroxyl dendrimer magnetic nanoparticles (Fe₃O₄@SiO₂‐TRIS) was studied in a batch system. The Fe₃O₄@SiO₂‐TRIS NPs were characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, and transmission electron microscopy. Experiments were performed under different conditions such as the initial dye concentration, adsorbent dose, and pH. The pseudo‐second‐order model provided a very good fit for the two anionic dyes. The Langmuir and Freundlich adsorption models were used to describe the equilibrium isotherms at different temperatures, and the former agreed very well with the experimental data. However, the adsorption capacity of Fe₃O₄@SiO₂‐TRIS NPs was reduced during surface modification, which could be due to the dye occupying the binding sites of the dendrimer. Thermodynamic parameters, namely the change in free energy (ΔG⁰), enthalpy (ΔH⁰), and entropy (ΔS⁰), were also determined.     

Synthesis and exploring the excited-state PES of photochromic hydrogen bond-assembled [2]rotaxane based on 1,3-Diazabicyclo-[3.1.0]hex-3-enes

Here, the synthesis of photochromic hydrogen bond-assembled [2]rotaxanes using bis-fumarate as a thread for the first time is reported. In fact, photochromic 1,3-diazabicyclo[3.1.0]hex-3-ene moieties were used as stoppers and two-atom spacers managed good binding sites for the tetralactam macrocycles in clipping reactions. Moreover, the yields of photochromic [2]rotaxanes highly depended on the NO₂ substituent stoppers. While the thread with a para –NO₂ substituent as stopper units was shown to be an excellent template for the synthesis of photochromic [2]rotaxanes. The structures of the [2]rotaxanes are established clearly in solution by chemical shifts of the ¹H ¹³C NMR signals and UV–Vis spectra. A pronounced bathochromic shift was occurred in the excitation wavelength of photochoromic [2]rotaxanes compared with the absorption band of photochromic threads. Therefore, these organizations can be applied in light-driven molecular switches and motors. The reversible transformation of trans and cis geometric photoisomers under UV radiation was identified. In other efforts, the possibility of the process of trans to cis interconversion of the fumarate linker under UV irradiation has been examined computationally and it has appeared that it may cause the transverse of the bis-fumarate linker inside the tetralactam macrocycle to some extent.