Fluoride-Ion-Catalyzed Synthesis of Ladder-type Conjugated Benzobisbenzofurans via Intramolecular Nucleophilic Aromatic Substitution Reaction under Metal-free and Mild Conditions

The fluoride-ion-catalyzed synthesis of benzobisbenzofuran derivatives is described. Fluorine-containing aryl silyl ethers were reacted with 5 mol % of Bu₄NF to give desired compounds in high yield under mild conditions. Syn-selective cyclization reaction was discovered for a particular compound as a kinetic product. Computational analysis revealed that the fluorine substituents in the anti-type benzobisbenzofurans affect the order of the molecular orbitals.

Synthesis, structural characterization and antimicrobial activities of 4- and 6-coordinate nickel(II) complexes with three thiosemicarbazones and semicarbazone ligands

To investigate the relationship between antimicrobial activities and the molecular structures of nickel(II) complexes with thiosemicarbazone and semicarbazone ligands, nickel(II) complexes with ligands Hmtsc, Hatsc, Hasc and H2dmtsc, were prepared and characterized by elemental analysis, FT-IR, 1H and 13C NMR spectroscopies, magnetic susceptibility measurements, UV-Vis absorption spectra, TG/DTA and single-crystal X-ray analysis. Their antimicrobial activities were evaluated by the MIC against four bacteria (B. subtilis, S. aureus, E. coli and P. aeruginosa), two yeasts (C. albicans and S. cerevisiae) and two molds (A. niger and P. citrinum). The 4-coordinate, diamagnetic nickel(II) complexes showed antimicrobial activities which were different from those of free ligands or the starting nickel(II) compounds; [Ni(mtsc)(OAc)] 1 showed selective and effective antimicrobial activities against two Gram-positive bacteria (B. subtilis and S. aureus) and modest activities against a yeast (S. cerevisiae), [Ni(mtsc)Cl] 3 exhibited moderate activities against a Gram-positive bacterium (S. aureus), and [Ni(atsc)(OAc)] 5 showed modest activities against two Gram-positive bacteria (B. subtilis and S. aureus). On the other hand, the 6-coordinate, paramagnetic nickel(II) complexes with two protonated or deprotonated ligands ([Ni(mtsc)2] 2, [Ni(atsc)(mtsc)] 4, [Ni(atsc)2] 6, [Ni(Hatsc)2](NO3)(2)7, [Ni(Hatsc)2]Cl(2)8 and [Ni(Hasc)2](OAc)(2)9) and the sterically crowded 4-coordinate, diamagnetic nickel(II) complex ([Ni(dmtsc)] 10) did not inhibit the growth of the test organisms. The structure-activity correlation in this series of nickel(II) complexes was discussed based on their ligand-replacement abilities.

[The relation of dental examination results at corporation offices to occupation, subjective symptoms of fatigue and daily lifestyle--an investigation based on the number of missing teeth]

Our investigation was intended to find a relationship between the dental health of labourers and, their jobs, subjective symptoms of fatigue and daily lifestyle. Dentists checked the dental health of 2,565 corporation employees (790 male and 775 female) of small to medium-sized enterprises in Hiroshima prefecture. At the same time they examined the employees' occupation, subjective symptoms of fatigue and their health maintenance behavior according to Breslow's criteria. The data were divided into age groups spanning 10 years. Among males in their 30s, those engaged in transport/driving and engineering/production had more missing teeth than others. We found a relationship between the number of missing teeth and subjective symptoms of fatigue among men in their 30s. This suggests that the greater the number of missing teeth, the greater their subjective symptoms of fatigue. The results suggest that missing teeth cause malocclusion which leads to subjective symptoms of fatigue.

[Clinical study of carumonam]

To evaluate the clinical efficacy of carumonam (CRMN, AMA-1080), the drug was used in the treatment of 10 patients including 4 with pneumonia and each with acute tonsillitis, chronic bronchitis, Mycoplasma pneumonia, primary atypical pneumonia (PAP), chronic pyelitis, and acute cystitis. Since beta-lactam antibiotics were not active against Mycoplasma pneumonia and PAP, these diseases were excluded from the clinical efficacy evaluation of CRMN. Responses were excellent in 1 patient and good in 7. Side effects were not observed. The laboratory test recognized slight elevations of GOT, GPT and eosinophilia in 1 patient and a slight leucopenia in another upon the administration of CRMN.