Cerium oxide-catalyzed multicomponent condensation approach to spirooxindoles in water

Design, synthesis, and apoptotic evaluation of spiro[indoline-3,3'-pyrazolo[1,2-a]indazole] derivatives via [3 + 2] N,N-cycloaddition

An efficient protocol for the synthesis of spiro[indoline-3,3'-pyrazolo[1,2-a]indazole] derivatives was developed via a [3 + 2] N,N-cycloaddition strategy, utilizing substituted 2-(2-oxoindolin-3-ylidene)malononitrile derivatives and 1,2-dihydro-3H-indazol-3-one under mild conditions, yielding excellent results (3a-3l). Furthermore, selected derivatives (3e and 3h-3l) were evaluated for cytotoxicity against various cancer cell lines, including MCF-7 (breast cancer), A549 (lung cancer), Colo-205 (colon cancer), and A2780 (ovarian cancer). The IC50 values ranged from 1.34 ± 0.21 μM (for 3l against MCF-7) to 8.53 ± 1.49 μM (for 3h against A2780). Notably, derivative 3l demonstrated the most potent apoptotic activity, exhibiting the lowest IC50 values across all four cancer cell lines. Additionally, molecular docking studies corroborated the observed biological activity, suggesting that these compounds may interact with relevant cellular targets, potentially accounting for their cytotoxic effects.

Recent advances in nanoparticles towards sustainability and their application in organic transformations in aqueous media

Nanoparticles (NPs) play a crucial role in organic transformation and are becoming increasingly attractive in the field of catalysis as they show good catalytic activity in organic as well as aqueous media. Numerous NPs have been utilized for several organic transformations in aqueous media, which have led to dedicated efforts for the complete coverage of the application of metal, metal oxide, bimetallic and supported NPs in water-mediated organic transformations in the last decades. This review aims to provide current highlights on the application of various types of metal NPs for organic transformations in aqueous media. The remarkable benefits associated with the catalytic application of NPs in water allows for various transformations to be performed under very mild and green conditions. Lastly, the author's perspectives are briefly considered, including future developments and crucial challenges in the ever-growing field of nanocatalysis.

Spirocyclic derivatives as antioxidants: a review

In recent years, spiro compounds have attracted significant interest in medicinal chemistry due to their numerous biological activities attributed primarily to their versatility and structural similarity to important pharmacophore centers. Currently, the development of drugs with potential antioxidant activities is of great importance since numerous investigations have shown that oxidative stress is involved in the development and progression of numerous diseases such as cancer, senile cataracts, kidney failure, diabetes, high blood pressure, cirrhosis, and neurodegenerative diseases, among others. This article provides an overview of the synthesis and various antioxidant activities found in naturally occurring and synthetic spiro compounds. Among the antioxidant activities reviewed are DPPH, ABTS, FRAP, anti-LPO, superoxide, xanthine oxidase, peroxide, hydroxyl, and nitric oxide tests, among others. Molecules that presented best results for these tests were spiro compounds G14, C12, D41, C18, C15, D5, D11, E1, and C14. In general, most active compounds are characterized for having at least one oxygen atom; an important number of them (around 35%) are phenolic compounds, and in molecules where this functional group was absent, aryl ethers and nitrogen-containing functional groups such as amine and amides could be found. Recent advances in the antioxidant activity profiles of spiro compounds have shown that they have a significant position in discovering drugs with potential antioxidant activities.

Waste foundry sand/MgFe-layered double hydroxides composite material for efficient removal of Congo red dye from aqueous solution

We aimed to obtain magnesium/iron (Mg/Fe)-layered double hydroxides (LDHs) nanoparticles-immobilized on waste foundry sand-a byproduct of the metal casting industry. XRD and FT-IR tests were applied to characterize the prepared sorbent. The results revealed that a new peak reflected LDHs nanoparticles. In addition, SEM-EDS mapping confirmed that the coating process was appropriate. Sorption tests for the interaction of this sorbent with an aqueous solution contaminated with Congo red dye revealed the efficacy of this material where the maximum adsorption capacity reached approximately 9127.08 mg/g. The pseudo-first-order and pseudo-second-order kinetic models helped to describe the sorption measurements, indicating that the physical and chemical forces governed the removal process.

Catalytic Organic Reactions in Water toward Sustainable Society

Traditional organic synthesis relies heavily on organic solvents for a multitude of tasks, including dissolving the components and facilitating chemical reactions, because many reagents and reactive species are incompatible or immiscible with water. Given that they are used in vast quantities as compared to reactants, solvents have been the focus of environmental concerns. Along with reducing the environmental impact of organic synthesis, the use of water as a reaction medium also benefits chemical processes by simplifying operations, allowing mild reaction conditions, and sometimes delivering unforeseen reactivities and selectivities. After the "watershed" in organic synthesis revealed the importance of water, the development of water-compatible catalysts has flourished, triggering a quantum leap in water-centered organic synthesis. Given that organic compounds are typically practically insoluble in water, simple extractive workup can readily separate a water-soluble homogeneous catalyst as an aqueous solution from a product that is soluble in organic solvents. In contrast, the use of heterogeneous catalysts facilitates catalyst recycling by allowing simple centrifugation and filtration methods to be used. This Review addresses advances over the past decade in catalytic reactions using water as a reaction medium.

Synthesis and Crystal Structure of a New Hydrated Benzimidazolium Salt Containing Spiro Structure

A new hydrated benzimidazolium salt containing spiro structure was obtained when benzimidazole is added to ethyl alcohol of 1,5-dioxaspiro[5.5]undecane-2,4-dione and trimethoxymethane. The title compound (C19H21O8) (C7H7N2) (0.5H2O) was characterized by elemental analysis, IR, UV-Vis, and single-crystal X-ray diffraction. The result shows that it belongs to the triclinic system, space group P-1, with a = 11.017(2) Å, b = 11.424(2) Å, c = 11.650(2) Å, α = 70.60(3)°, β = 71.00(3)°, γ = 67.64(3)°, Mr = 505.51, V = 1245.2(5) Å, Z = 2, Dc = 1.348 g/cm3, F(000) = 534, μ(MoKa) = 0.102 mm−1. There exist two types of hydrogen bonds in the crystal. (C19H21O8)− anions and (C7H7N2)+ cations are linked by N–H···O hydrogen bonds, while (C19H21O8)− anions and free water are linked by O–H···O hydrogen bonds. All of the above hydrogen bonds form a one-dimensional (1D)-chained structure. The 1D chains further links the molecule into a three-dimensional (3D)-layered structure.