Multicomponent Synthesis of 4-Aryl-4,9-dihydro-1-pyrazolo[3,4-]quinolines Using L-Proline as a Catalyst-Does It Really Proceed?

Looking for effective synthetic methods for 1-pyrazolo[3,4-]quinolines preparation, we came across a procedure where, in a three-component reaction catalysed by L-proline, 4-aryl-4,9-dihydro-1-pyrazolo[3,4-]quinolines are formed. These compounds can be easily oxidised to a fully aromatic system, which gives hope for a synthetic method that could replace, e.g.

1-Pyrazolo[3,4-]quinolines: Synthesis and Properties over 100 Years of Research.

This paper summarises a little over 100 years of research on the synthesis and the photophysical and biological properties of 1-pyrazolo[3,4-]quinolines that was published in the years 1911-2021. The main methods of synthesis are described, which include Friedländer condensation, synthesis from anthranilic acid derivatives, multicomponent synthesis and others. The use of this class of compounds as potential fluorescent sensors and biologically active compounds is shown.

Furcellaran nanocomposite films: The effect of nanofillers on the structural, thermal, mechanical and antimicrobial properties of biopolymer films.

Graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs) were added to furcellaran films (FUR). Silver nanoparticles (AgNPs) were prepared by reducing AgNO using a FUR matrix as the stabilising agent. The structure and surface morphology of nanocomposite films were obtained using FTIR, SEM and XRD.

Spectral Properties of Highly Emissive Derivative of Coumarin with N,N-Diethylamino, Nitrile and Tiophenecarbonyl Moieties in Water-Methanol Mixture.

The new derivative of coumarin (E)-3-[7-(diethyloamino)-2-oxo-chromen-3yl]-2-(tiophene-2-carbonyl)prop-2-enenitrile (NOSQ) was easy synthesized with commercial substrates as a result of the search of new Michael type addition sensors based on coumarins. Spectral properties of highly emissive NOSQ were investigated by steady state analysis (absorption and fluorescence measurements) and time-resolved analysis (fluorescence lifetime measurements). The effect of water-methanol mixture on the photophysical properties of the NOSQ molecule was analyzed.

Investigation of the physical properties, antioxidant and antimicrobial activity of ternary potato starch-furcellaran-gelatin films incorporated with lavender essential oil.

Lavender essential oil (OEL) was added to starch, furcellaran and gelatin (S/F/G) films in concentrations of 2%, 4% and 6%. The films were examined in terms of physical properties (thickness, density, water solubility, water absorption and degree of swelling) and mechanical properties (tensile strength, elongation at break). The test results show that the film thickness increased upon addition of OEL.

Stationary and time-resolved spectra analysis of pyrazoloquinoline derivatives with pyridyl moiety.

Two derivatives of pyrazoloquinoline with pyridyl moiety: 6-N,N-dimethyl-3-phenyl-1-(2-pyridyl)-1H-pyrazolo[3,4-b]quinoline (DMA-1PPhPQ) and 6-N,N-dimethyl-1,3-(di-2-pyridyl)-1H-pyrazolo[3,4-b]quinoline (DMA-1,3PPQ) were synthesized with commercial substrates. The theoretical characterization of both compounds was done. Geometry optimizations give not flat structure with the first absorption band at the wavelength about 390nm for both compounds.

Novel scintillating material 2-(4-styrylphenyl)benzoxazole for the fully digital and MRI compatible J-PET tomograph based on plastic scintillators.

A novel plastic scintillator is developed for the application in the digital positron emission tomography (PET). The novelty of the concept lies in application of the 2-(4-styrylphenyl)benzoxazole as a wavelength shifter. The substance has not been used as scintillator dopant before.