Development of a Novel Antibacterial Medicine that Targets a Characteristic Lipid of the Cell Membranes of <em>Helicobacter pylori</em>

Helicobacter pylori is one of the most prevalent causes of gastritis. This pathogen colonizes for many years human stomach and asymptomatically leads the persons to chronic gastritis. The eradication of H. pylori from human stomach is, therefore, important in order to prevent the digestive diseases including peptic ulcers and gastric cancer that develop via chronic atrophic gastritis. Wide-spectrum antibiotics such as amoxicillin and metronidazole are used for the treatment for H. pylori infectious diseases. However, the H. pylori strains resistant to these antibiotics are increasing year by year around the world. On this basis, we need urgently to develop the antibacterial medicines that act on H. pylori with a novel mechanism. Recent studies by our group have demonstrated that H. pylori shows susceptibility to the bactericidal action of indene compounds derived from decomposition of vitamin D. The bactericidal action of indene compounds is selective not against commonplace bacteria but against H. pylori. The indene compounds turned out to target the H. pylori’s phosphatidylethanolamine that retains a myristic acid as the saturated fatty acid side chain. These findings will contribute to the development of new antibacterial medicines specialized to the treatment for H. pylori infectious diseases

A-band methyl halide dissociation via electronic curve crossing as studied by electron energy loss spectroscopy

Excitation of the A-band low-lying electronic states in the methyl halides, CH3I, CH3Br, CH3Cl, and CH3F, has been investigated for the (n→σ∗) transitions, using electron energy loss spectroscopy (EELS) in the range of 3.5–7.5 eV. For the methyl halides, CH3I, CH3Br, and CH3Cl, three components of the Q complex (3Q1, 3Q0, and 1Q1) were directly observed, with the exception of methyl fluoride, in the optically forbidden EELS experimental conditions of this investigation. The effect of electronic-state curve crossing emerged in the transition probabilities for the 3Q0 and 1Q1 states, with spin-orbit splitting observed and quantified against results from recent ab initio studies

Solution-phase automated synthesis of an α-amino aldehyde as a versatile intermediate

A solution-phase automated synthesis of the versatile synthetic intermediate, Garner’s aldehyde, was demonstrated. tert-Butoxycarbonyl (Boc) protection, acetal formation, and reduction of the ester to the corresponding aldehyde were performed utilizing our originally developed automated synthesizer, ChemKonzert. The developed procedure was also useful for the synthesis of Garner’s aldehyde analogues possessing fluorenylmethyloxycarbonyl (Fmoc) or benzyloxycarbonyl (Cbz) protection

One-Pot, Three-Component Coupling Approach to the Synthesis of α–Iminocarboxamides

A one-pot, three-component coupling was accomplished via the nucleophilic addition of an alkylsamarium(III) species to isocyanides and the subsequent addition of the resultant imidoyl samarium(III) species to isocyanates under mild conditions for the formation of α-iminocarboxamides. The developed sequential C–C bond-forming procedure enabled the rapid synthesis of the α-iminocarboxamides in good to excellent yields from readily available starting materials

Effects of Growth Temperature and Postgrowth Annealing on Inhomogeneous Luminescence Characteristics of Green-Emitting InGaN Films

Microscopic photoluminescence was applied to investigate μm-order inhomogeneity of InGaN alloys. Samples had InGaN/GaN multiple-quantum-well structures grown on sapphire substrates at various temperatures, and luminescence was adjusted to be green. Luminescence morphologies of dendritic appearance were observed on as-grown samples. Bright spots luminescing at long wavelengths (green to amber) were formed at high growth temperatures. After annealing at 1000°C, the bright spots disappeared and the dendritic morphology turned into a granular morphology. Because of these μm-order inhomogeneities, it has been suggested that small-scale characterization (sub-μm or smaller) requires special attention in order not to miss effects of μm-order inhomogeneity in InGaN alloys