Dioxygenase Chemistry in Nucleophilic Aldehyde Deformylations Utilizing Dicopper O-Derived Peroxide Complexes.

The chemistry of copper-dioxygen complexes is relevant to copper enzymes in biology as well as in (ligand)Cu-O (or Cu-O) species utilized in oxidative transformations. For overall energy considerations, as applicable in chemical synthesis, it is beneficial to have an appropriate atom economy; both O-atoms of O are transferred to the product(s). However, examples of such dioxygenase-type chemistry are extremely rare or not well documented.

Study on Chemical Composition and Biological Activity of Leaf Extracts.

Guava () is a plant widely distributed in tropical and subtropical regions. Its leaves contain a large amount of physiological molecules such as flavonoid, sesquiterpene, triterpenoid, coumarin, alkaloid, and tannin molecules with antioxidative and anti-inflammatory effects. In this study, the use of concentrated .

Ligand-Copper(I) Primary O-Adducts: Design, Characterization, and Biological Significance of Cupric-Superoxides.

In this Account, we overview and highlight synthetic bioinorganic chemistry focused on initial adducts formed from the reaction of reduced ligand-copper(I) coordination complexes with molecular oxygen, reactions that produce ligand-Cu(O) complexes (O ≡ superoxide anion). We provide mostly a historical perspective, starting in the Karlin research group in the 1980s, emphasizing the ligand design and ligand effects, structure, and spectroscopy of these O adducts and subsequent further reactivity with substrates, including the interaction with a second ligand-Cu complex to form binuclear species. The Account emphasizes the approach, evolution, and results obtained in the Karlin group, a synthetic bioinorganic research program inspired by the state of knowledge and insights obtained on enzymes possessing copper ion active sites which process molecular oxygen.

Fenton-like Chemistry by a Copper(I) Complex and HO Relevant to Enzyme Peroxygenase C-H Hydroxylation.

Lytic polysaccharide monooxygenases have received significant attention as catalytic convertors of biomass to biofuel. Recent studies suggest that its peroxygenase activity (i.e.

Concluding remarks: discussion on natural and artificial enzymes including synthetic models.

This paper overviews the final remarks lecture delivered (by K. D. K.

Challenges of Measuring Soluble Mn(III) Species in Natural Samples.

Soluble Mn(III)-L complexes appear to constitute a substantial portion of manganese (Mn) in many environments and serve as critical high-potential species for biogeochemical processes. However, the inherent reactivity and lability of these complexes-the same chemical characteristics that make them uniquely important in biogeochemistry-also make them incredibly difficult to measure. Here we present experimental results demonstrating the limits of common analytical methods used to quantify these complexes.

Pulsed electromagnetic field potentiates etoposide-induced MCF-7 cell death.

Etoposide is a chemotherapeutic medication used to treat various types of cancer, including breast cancer. It is established that pulsed electromagnetic field (PEMF) therapy can enhance the effects of anti-cancer chemotherapeutic agents. In this study, we investigated whether PEMFs influence the anti-cancer effects of etoposide in MCF-7 cells and determined the signal pathways affected by PEMFs.

Redox-Inactive Metal Ions That Enhance the Nucleophilic Reactivity of an Alkylperoxocopper(II) Complex.

The importance of redox-inactive metal ions in modulating the reactivity of redox-active biological systems is a subject of great current interest. In this work, the effect of redox-inactive metal ions (M = Sc, Y, Yb, La) on the nucleophilic reactivity of a mononuclear ligand-based alkylperoxocopper(II) complex, [Cu(Pr-tren-C(CH)O)] (), was examined. was prepared by the addition of hydrogen peroxide and triethylamine to the solution of [Cu(Pr-tren)(CHCN)] (Pr-tren = tris[2-(isopropylamino)ethyl]amine) via the formation of [Cu(Pr-tren)(OH)] () in methanol (CHOH) at 30 °C.

Development and structure-activity relationship study of SHP2 inhibitor containing 3,4,6-trihydroxy-5-oxo-5H-benzo[7]annulene.

SHP2, a non-receptor protein tyrosine phosphatase encoded by PTPN11 gene, plays an important role in the cell growth and proliferation. Activating mutations of SHP2 have been reported as a cause of various human diseases such as solid tumors, leukemia, and Noonan syndrome. The discovery of SHP2 inhibitor can be a potent candidate for the treatment of cancers and SHP2 related human diseases.

Effects of Mo addition on crack tip opening displacement (CTOD) in heat affected zones (HAZs) of high-strength low-alloy (HSLA) steels.

Effects of Mo addition on microstructures and crack tip opening displacement (CTOD) in heat affected zones (HAZs) of three high-strength low-alloy (HSLA) steels were investigated in this study, and the correlation between them was explained by fracture mechanisms related with martensite-austenite constituent (MA) characteristics. The coarse-grained HAZ (CGHAZ) consisted of acicular ferrite (AF), granular bainite (GB), and bainitic ferrite (BF), whereas the inter-critically heated HAZ (ICHAZ) consisted of quasi-polygonal ferrite (QPF), GB, and MA. Since Mo promoted the formation of GB, BF, and MA and prevented the formation of AF and QPF, the CTOD decreased in both HAZs with increasing Mo content.

Visualization of MMP-2 Activity Using Dual-Probe Nanoparticles to Detect Potential Metastatic Cancer Cells.

Matrix metalloproteinases (MMPs) are a family of zinc-dependent enzymes capable of degrading extracellular matrix components. Previous studies have shown that the upregulation of MMP-2 is closely related to metastatic cancers. While Western blotting, zymography, and Enzyme-Linked Immunosorbent Assays (ELISA) can be used to measure the amount of MMP-2 activity, it is not possible to visualize the dynamic MMP-2 activities of cancer cells using these techniques.

Nucleophilic reactivity of copper(ii)-alkylperoxo complexes.

Copper(ii)-alkylperoxo adducts, [Cu(CHDAP)(OOR)] (CHDAP = N,N'-dicyclohexyl-2,11-diaza[3,3](2,6)pyridinophane; R = C(CH)Ph and Bu), were prepared and characterized using various physicochemical methods. These are the first synthetic Cu(ii)-alkylperoxo complexes that can perform aldehyde deformylation (i.e.