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Nitrobenzofurazan derivatives are well known for their fluorescence, whilst crown ethers are known for their complexing capacity toward cationic species. In this study, we present the synthesis and structural characterization of a new derivative containing both nitrobenzofurazan moieties and a crown ether core. The new compound was obtained from dibenzo-18-crown-6 ether, which was first nitrated, reduced to the corresponding amine, and subsequently derivatized with NBD. Structural analyses performed by IR, NMR, UV–Vis, and MS confirmed its structure and physico-chemical behavior toward the complexation of alkaline cations.

Five new derivatives were obtained utilizing 4-chloro-7-nitrobenzofurazan (NBD-chloride) in combination with furfurylamine, adamantylamine, aminohippuric acid, phenylalanine, and dehydroabietylamine. These derivatives were then subjected to a comparative analysis of their physical, chemical, and certain biological properties alongside two analogous and known compounds derived from the glycine and 4-amino-TEMPO free radical.

New aspects of the Ni(II)-salophen complex and salophen ligand precursor were found during deep electrochemical and optical characterization, as well as biological studies for new pharmacological applications. Physicochemical and spectroscopic methods (1H- and 13C-NMR, FT-IR and UV-Vis, electrospray ionization mass spectroscopy, thermogravimetric analysis, and molar conductance measurements) were also used to prove that the salophen ligand acts as a tetradentate and coordinates to the central metal through nitrogen and oxygen atoms. The electrochemical behavior of the free Schiff salophen ligand (H2L) and its Ni(II) complex (Ni(II)L) was deeply studied in tetrabutylammonium perchlorate solutions in acetonitrile via CV, DPV, and RDE. Blue films on the surfaces of the electrodes as a result of the electropolymerization processes were put in evidence and characterized via CV and DPV. (H2L) and Ni(II)L complexes were tested for their antimicrobial, antifungal, and antioxidant activity, showing good antimicrobial and antifungal activity against several bacteria and fungi.

Background: New amino derivatives of NBD type are of high interest due to their strong fluorescence, while compounds containing a disulphide moiety are of high interest in nano-chemistry due to their easiness of attaching to noble nanoparticles. Therefore, in this work a new fluorescent derivative of NBD and cystamine was obtained. Methods: The reaction between cystamine and NBD-chloride occurs straightforwardly, and the isolated new compound was characterized by IR, UV-Vis, fluorescence, 1H- and 13C-NMR, MS, etc. Results: Structural analysis confirmed the proposed structure and highlighted the fluorescence behavior. Conclusions: A new fluorescent derivative of cystamine was obtained and characterized by different means.

4-Aminodiphenylamino derivatives were investigated for their antioxidant and hydrophobicity character, together with other biological measurements, such as antimicrobial and antibiofilm activity. Among these nine compounds used, we obtained novel derivatives via reaction of the starting material with NBD-chloride. Therefore, we performed a full structural analysis for these compounds, i.e., elemental analysis, IR, UV-Vis, 1H- and 13C-NMR, ESI-MS, X-ray diffraction on single crystal, etc. The hydrophobicity of all the compounds was measured either experimentally using the RP-TLC technique, or via calculation using the fragments method. The other structural characteristics were analyzed, and a correlation between the experimental and computed properties was found. Moreover, the results of the biological evaluation showed that some of the synthesized compounds have antimicrobial and antibiofilm activity.

As a continuation of research on 1-vinylazulenes synthesis, on their physico–chemical properties as well as on their use as colorimetric and electrochemical materials for the detection of heavy metals ions, new compounds, 4-(azulen-1-ylmethylene)-2-phenyloxazol-5(4H)-ones, are reported. The exceptional structure of azulene moiety with symmetrical electron distribution only with respect to the x-axis gives some special chemical and physical properties to compounds in which it is inserted. Various azulene-1-carbaldehydes and hippuric acids are condensed with good yields in Erlenmeyer—Plöchl reaction conditions. The obtained 1-vinylzulenes were characterized and their UV-Vis and NMR spectra were briefly discussed.

Two N-substituted amides (N-acryloyl morpholine and N-methyl-N-vinylacetamide) were polymerized in different solvents using radical initiator. The tacticity of obtained polymers was determined by 400 MHz 1H-NMR and 13C-NMR. At a given temperature, the syndiotacticity increased with increasing the solvent polarity. This solvent effect may be related to the hydrogen bonding interaction among solvent, monomer, and/or growing species. A peculiar aspect regards the steric hindrance at the nitrogen atom.

Cotinus coggygria Scop. (smoketree) is a phytotherapeutically valuable shrub growing in specific areas in many Eurasian countries. Exploring the intrinsic and extrinsic (abiotic) factors that modulate its secondary metabolism has fundamental and applicative importance. Three smoketree plants from the same population were studied for a period of 4.5 months. Their extracts were characterized using LC–MS/MS, HPLC–UV–VIS–DAD and colorimetric assays to determine the chemical composition and antioxidant potential. Multivariate analysis was applied to correlate the metabolomic data with registered habitat variables and phenological stages. The identified and quantified compounds belonged to the flavonoids (myricetin-3-O-galactoside, myricitrin) and hydrolysable tannins groups (pentagalloyl glucose, methyl gallate, methyl digallate I). Phenolic compounds and tannins were synthesized abundantly in the flowering and fruit stages, whereas flavonoids and triterpenes accumulated during senescence. The antioxidant activities varied between detection methods, samplings and individuals and were only punctually correlated with the compound contents in certain phenological stages. Based on the HCAbp analysis, the samples clustered under four groups, according to their metabolic profile. The CCA analysis revealed that during the reproductive stages (flower, fruit or seed), the secondary metabolism of the plants’ leaves is sensitive to the action of abiotic factors, while in senescence, the metabolic content is according to the phenological phase. This study provides a first attempt at understanding the interplay between the habitat and the metabolome of smoketree.

Through time, in the traditional medicine Ligularia genus has been used as a remedy to cure several diseases and affections. The paper represents an essential step in offering more information about the antioxidant activity, chemical composition and cytogenetic activity of L. sibirica (L.) Cass. rhizomes and roots extracts. The antioxidant activity of the extracts has been achieved by analyzing the total phenolic content, total flavonoids, the organic chemical compound and trolox equivalent antioxidant capacity and their major polyphenolic constituents were quantified by liquid chromatography electrospray ionization-tandem mass spectrometry. The extracts were obtained by the Supercritical Fluid Extraction (SFE-CO2) technique, SFE-CO2 extraction with co-solvent and absolute ethanol extraction. The best results for the antioxidant activity have been fulfilled through the last two techniques. High Performance Liquid Cromatography (HPLC) has been applied in order to identify and quantify selected phenolic acids and flavonoids in the ethanolic extracts of L. sibirica (L.) Cass. The cytogenotoxic effects of the extracts completed the present study, with a furtherance of antiproliferative potential highlighted by the statmokinetic effect and an additional genoprotective effect.