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We designed and synthesized a series of derivatives containing the right-side DFGH-ring structure of physalin-type natural products, decorated with a hydrophobic substituent. The synthetic scheme utilizes a highly efficient, one-pot protocol for simultaneous construction of the GH-ring system, promoted by HF/pyridine. Among the compounds synthesized, 5dinhibited TNF-α-stimulated NF-κB activation with similar potency to physalin B.

A new synthetic method for π-conjugated fused oligosiloles has been developed by combining a rhodium-catalyzed stitching reaction and subsequent remote conjugate elimination. Aromatization-driven 1,8-, 1,10-, or 1,12-dehydration was successfully utilized and up to 3 silole units were consecutively fused in a π-conjugated manner. The structural change upon conjugate elimination was confirmed by using X-ray crystallographic analysis, and the optical and electrochemical properties of a series of newly synthesized fused oligosiloles were also examined.A new synthetic method for π-conjugated fused oligosiloles was developed by combining a rhodium-catalyzed stitching reaction and subsequent remote conjugate elimination, and up to 3 silole units were consecutively fused in a π-conjugated manner. The structural change upon conjugate elimination was confirmed by using X-ray crystallographic analysis, and the optical and electrochemical properties of newly synthesized fused oligosiloles were also examined.

Quantitative analysis of nitrilotriacetate (NTA) in detergents by titration with Cu2+solution using a copper ion selective electrode was achieved. This method tolerates a wide range of pH and ingredients in detergents. In addition to NTA, other chelating agents, having relatively lower stability constants toward Cu2+, were also qualified with sufficient accuracy by this analytical method for model detergent formulations. The titration process was automated by automatic titrating systems available commercially.

The enhanced effect of chemiluminescence (CL) of lucigenin (Luc2+) at a flat liquid/liquid interface and at O/W emulsions was demonstrated. The CL was emitted when Luc2+was transferred from an organic phase to an aqueous one containing NaOH and H2O2. The CL intensity and emission spectrum depended strongly on the kind of organic solvent. We attempted to apply the CL reaction of Luc2+in the O/W emulsion system to the analysis of H2O2. The available analytical conditions were discussed from the aspects of the kind of organic solvent, the reaction time and wavelength detected.

We have studied amino acid formation by UV (193 nm) irradiation to organic molecules (amines, alcohols and amides) in aqueous solution. Among several types of detected amino acids, small aliphatic amino acids (Gly and α-, β-Ala and α-, β-, γ-ABA) were quantitatively identified. Among these small aliphatic amino acids, certain amino acids were formed in its free form, even before hydrolysis, contrary to the results of UV irradiation to a gas mixture of CO, NH3, and H2O, where amino acids were hardly detected before hydrolysis. The species distribution of identified amino acids showed a dependence on the starting organic molecules, and also on the presence of ammonia. The formation processes of the identified small aliphatic amino acids were investigated with the aid of electrospray ionization (ESI) MS and MS/MS measurements of photoproducts. Possible formation processes of these amino acid precursors from each starting molecules are proposed. By identifying the amino acid precursor, which has a chiral carbon atom, a new possibility is suggested for asymmetric photosynthesis of amino acid from achiral organic molecules.

The reactions of fluorinated ylide, generated from tris(dimethylamino)phosphine and tribromofluoromethane, with simple aldehydes and reactive ketones gave the expected Wittig reaction products. However, a ketone having a galactose skeleton afforded an acid fluoride, probably through an unprecedented Corey–Chaykovski-type epoxide formation reaction, followed by spontaneous Meinwald rearrangement.

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