The widespread usage of Schiff bases in chemistry, industry, medicine, and pharmacy has increased interest in these compounds. Schiff bases and derivative compounds have important bioactive properties. Heterocyclic compounds containing phenol derivative groups in their structure have the potential to capture free radicals that can cause diseases. In this study, we designed and synthesized eight Schiff bases (10–15) and hydrazineylidene derivatives (16–17), which contain phenol moieties and have the potential to be used as synthetic antioxidants, for the first time using microwave energy. Additionally, the antioxidant effects of Schiff bases (10–15) and hydrazineylidene derivatives (16–17) were studied using by the bioanalytical methods of 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) cation radical (ABTS^•+) and 1,1-diphenyl-2-picrylhydrazyl (DPPH^•) scavenging activities, and Fe³⁺, Cu²⁺, and Fe³⁺-TPTZ complex reducing capacities. In the context of studies on antioxidants, Schiff bases (10–15) and hydrazineylidene derivatives (16–17) were found to be as powerful DPPH (IC₅₀: 12.15–99.01 μg/mL) and ABTS^•+ (IC₅₀: 4.30–34.65 μg/mL). Additionally, the inhibition abilities of Schiff bases (10–15) and hydrazineylidene derivatives (16–17) were determined towards some metabolic enzymes including acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and human carbonic anhydrase I and II (hCAs I and II), enzymes that are linked to some global disorders including Alzheimer’s disease (AD), epilepsy, and glaucoma. In the context of studies on enzyme inhibition, it was observed that the synthesized Schiff bases (10–15) and hydrazineylidene derivatives (16–17) inhibited AChE, BChE, hCAs I, and hCA II enzymes with IC₅₀ values in ranges of 16.11–57.75 nM, 19.80–53.31 nM, 26.08 ± 8.53 nM, and 85.79 ± 24.80 nM, respectively. In addition, in light of the results obtained, we hope that this study will be useful and guiding for the evaluation of biological activities in the fields of the food, medical, and pharmaceutical industries in the future.

Climbazole (CBZ) is an antifungal active pharmaceutical ingredient often used in antidandruff products. In this study, the ketone group in the racemic CBZ molecule was reduced to synthesize CBZ-alcohol, named 1-(4-chlorophenoxy)-1-(1H-imidazol-1-yl)-3,3-dimethylbutan-2-ol, and the optimum adsorption conditions were investigated for removing iron(II) (Fe2+) ions from wastewater by adsorption from aqueous solutions using the economical and environmentally friendly ultrasonic method. The parameters and levels used in the study were designed using response surface methodology and model equations were derived to optimize the results. The independent variables selected were the initial pH (1, 3, and 5), adsorption time (30, 45, and 60 min), adsorption temperature (40, 60, and 80 °C), and Fe2+ ions consumption percentage from the wastewater. Experiments were conducted on a real wastewater sample taken from the Uşak Organized Industrial Zone. Conditions that maximize each dependent variable were specified separately and verification experiments were conducted under these conditions. Maximum Fe2+ ion consumption was 91.83%. The R2 value of the model was 0.9598. The findings demonstrate that CBZ-alcohol was effective as an adsorbent in Fe2+ ion removal from aqueous solution.

In the present study, new chalcone derivatives (5a–5f) obtained from the condensation reaction of cuminaldehyde and acetophenone compounds containing different substituents were reported. Chemical characterization (1HNMR and 13CNMR analysis) and molecular docking studies of the synthesized compounds were performed against the epidermal growth factor receptor (EGFR) and reference drug (metachalcone). Erlotinib was used as the reference ligand. Compound 5 (-7.6 kcal mol-1), compound 6 (-7.38 kcal mol-1), and compound 7 (-7.44 kcal mol-1) were found to be the strongest inhibitors of EGFR when compared to Erlotinib (-7.0 kcal mol-1). In addition, an ADME estimation was made. It was determined that the synthesized compounds could be potent EGFR inhibitors compared to Erlotinib. Compounds 5-7 and the target protein showed a better binding affinity for EGFR than the reference compound (Erlotinib). The synthesized compounds can be potent inhibitors for EGFR-mutated cancers.

To address the low corrosion resistance of conventional epoxy coatings, a smart nanocomposite was designed by using UiO-66-NH2, a metal–organic framework (MOF), loaded with a new Schiff base as an inhibitor. The MOFs were encapsulated with a pH-responsive shell, allowing for the controlled release of the inhibitor. The crystallinity of UiO-66-NH2 remained preserved after encapsulation, and spherical particles were observed with an apparent size increase following encapsulation. The specific surface area of UiO-66-NH2 decreased from 860.18 to 131.06 m² g^–1 and pore volume from 1.9745 to 0.2871 cm³ g^–1, indicating efficient pore occupation by the inhibitor. This change resulted in a loading efficiency of 30.5% and an encapsulation efficiency of 43.9%, which contribute to the enhanced corrosion resistance of the coating. The encapsulated UiO-66-NH2 exhibited smart behavior, releasing the highest amount of inhibitor at pH 12. The addition of UiO-66-NH2 and its encapsulated form eliminated micrometric defects in the coating, and the MOFs were uniformly distributed throughout the epoxy matrix. The incorporation of UiO-66-NH2 reduced the surface roughness of the epoxy coating from 3.909 to 3.260 μm, with a further decrease to 1.851 μm upon addition of its encapsulated form. Electrochemical impedance spectroscopy (EIS) studies in 0.2 M HCl revealed enhanced corrosion resistance after UiO-66-NH2 addition, mainly due to MOF-coating interactions, eliminating structural pores. After 6 weeks of immersion, the epoxy coating with encapsulated UiO-66-NH2 achieved a polarization resistance (R _p) of 327.33 MΩ cm², surpassing the neat epoxy coating by ∼41 times and the UiO-66-NH2-containing coating by ∼10 times. Potentiodynamic polarization (PDP) and postcorrosion morphology aligned well with EIS results. Density functional theory calculations confirmed the potential for chemical and physical adsorption of Schiff base molecules onto the steel. The coating designed in this study shows potential for protecting steel in industrial environments, including chemical processing plants and water treatment facilities.

It is known that compounds containing sulfur in their structure have a wide range of biological activities, such as antibacterial, antiallergic, antimicrobial, anticancer, and anticonvulsant. In addition, nitrogen-containing heterocyclic compounds are also found in nature and the structure of drugs. Various compounds, such as piperidine and its derivatives, are also widely used in the synthesis of many drugs. Various Schiff bases have been synthesized in drug development studies, and they have been used in clinical applications as drugs and drug candidates. In this context, the synthesis of new thiophene-based Schiff bases containing piperidine rings is aimed. Green chemistry objectives were adhered to in the syntheses. Thiophene-2-carbaldehyde and piperidine derivatives were used as starting compounds, and new compounds containing thiophene-based piperidine were synthesized without adding any catalyst or solvent to the reaction medium. The desired Schiff base compounds were successfully synthesized in high yield and in a short time.