Evaluation of anticancer activities varying ligand’s substituents in Co(II/III)-picolyl phenolate derivatives: Synthesis, characterization, DFT, DNA cleavage and molecular docking studies

The reaction between 2-(pyridine-2-ylmethoxy)-benzaldehyde (L) and various primary amines furnish tridentate (L1 to L3) and tetradentate (L4) chelating ligands. The choice of different primary amines in the condensation reaction incorporates...

Selective 1,2 addition of polar X‒H bonds to the Ga–P double bond of gallaphosphene L(Cl)GaPGaL

Gallaphosphene L(Cl)GaPGaL 1 (L = HC[C(Me)N(2,6-i-Pr2-C6H3)]2) reacts at ambient temperature with a series of polar X−H bonds, i.e. ammonia, primary amines, water, phenol, thiophenol, and selenophenol, selectively with 1,2 addition...

Study of uric acid oxidation reaction products in medium of ammonia or primary amines

This work is considered in more detail the most important stage of obtaining one of the promising heteroatomic polycyclic compounds 3,7,10-trioxo-2,4,6,8,9,11-hexaaza[3.3.3]propellane (THAP). THAP is a potential compound for creating high-energy substances due to the presence of six nitrogen atoms in the structure and tight packing. Uric acid is the starting compound in the THAP synthesis chain. When it is oxidized by sodium persulfate or potassium ferrocyanide, 1,5-diaminoglycoluril is formed, from which the propellane structure is formed by the tricyclization reaction. This work expanded the range of oxidants for the conversion of uric acid to 1,5-diaminoglycoluril. It was found that 1,5-diaminoglycoluril was formed with a yield of 29 % when using equimolar proportions of uric acid and KMnO4. When using MnO2 in a ten times more excess, the yield of 1,5-diaminoglycoluril was 38 %. The article also presents the results of a study of the interaction of uric acid with some amines. The reaction of interaction of uric acid with benzylamine was studied in more detail, the reaction products of which were 4-benzylimino-5-benzylaminoallantoin, 4- benzylimino-1-benzylamino-allantoin and 4-benzyliminoallantoin. Based on the synthesis of 4- benzyliminoallantoin, a number of promising derivatives of 4-iminoallantoin were obtained, namely 4- ethyliminoallantoin, 4-propyliminoallantoin, 4-i-propyliminoallantoin, 4-n-butyliminoallantoin, 4-i- butyliminoallantoin, 4-tert-butyliminoallantoin.

Silica-supported Fe/Fe–O nanoparticles for the catalytic hydrogenation of nitriles to amines in the presence of aluminium additives

The hydrogenation of nitriles to amines represents an important and frequently used industrial process due to the broad applicability of the resulting products in chemistry and life sciences. Despite the existing portfolio of catalysts reported for the hydrogenation of nitriles, the development of iron-based heterogeneous catalysts for this process is still a challenge. Here, we show that the impregnation and pyrolysis of iron(II) acetate on commercial silica produces a reusable Fe/Fe–O@SiO2 catalyst with a well-defined structure comprising the fayalite phase at the Si–Fe interface and α-Fe nanoparticles, covered by an ultrathin amorphous iron(III) oxide layer, growing from the silica matrix. These Fe/Fe–O core–shell nanoparticles, in the presence of catalytic amounts of aluminium additives, promote the hydrogenation of all kinds of nitriles, including structurally challenging and functionally diverse aromatic, heterocyclic, aliphatic and fatty nitriles, to produce primary amines under scalable and industrially viable conditions.

Curcumin-Piperlongumine Hybrids with a Multitarget Profile Elicit Neuroprotection in In Vitro Models of Oxidative Stress and Hyperphosphorylation

Curcumin shows a broad spectrum of activities of relevance in the treatment of Alzheimer’s disease (AD); however, it is poorly absorbed and is also chemically and metabolically unstable, leading to a very low oral bioavailability. A small library of hybrid compounds designed as curcumin analogues and incorporating the key structural fragment of piperlongumine, a natural neuroinflammation inhibitor, were synthesized by a two-step route that combines a three-component reaction between primary amines, β-ketoesters and α-haloesters and a base-promoted acylation with cinnamoyl chlorides. These compounds were predicted to have good oral absorption and CNS permeation, had good scavenging properties in the in vitro DPPH experiment and in a cellular assay based on the oxidation of dichlorofluorescin to a fluorescent species. The compounds showed low toxicity in two cellular models, were potent inductors of the Nrf2-ARE phase II antioxidant response, inhibited PHF6 peptide aggregation, closely related to Tau protein aggregation and were active against the LPS-induced inflammatory response. They also afforded neuroprotection against an oxidative insult induced by inhibition of the mitochondrial respiratory chain with the rotenone-oligomycin A combination and against Tau hyperphosphorylation induced by the phosphatase inhibitor okadaic acid. This multitarget pharmacological profile is highly promising in the development of treatments for AD and provides a good hit structure for future optimization efforts.

A Versatile AIE Fluorogen with Selective Reactivity to Primary Amines for Monitoring Amination, Protein Labeling and Mitochondrial Staining

Specific bioconjugation for native primary amines is highly valuable for both chemistry and biomedical research. Despite all the efforts, scientists lack a proper strategy to achieve high selectivity for primary amines, not to mention the requirement of fast response for real applications. Herein, in this work, we report a chromone-based aggregation-induced emission (AIE) fluorogen called CMVMN as a self-reporting bioconjugation reagent for selective primary amine identification, and its applications for monitoring bioprocesses of amination and protein labeling. CMVMN is AIE-active and is capable of solid-state sensing. Thus, its electrospun films are manufactured for visualization of amine diffusion and leakage process. CMVMN also shows good biocompatibility and potential mitochondria-staining ability, which provides new insight for organelle-staining probe design. Combined with its facile synthesis and good reversibility, CMVMN not only shows wide potential applications in biology, but also offers new possibilities for molecular engineering.