Mononuclear 16-electron arene−ruthenium(II)−thiolate complexes of the general formula (η6-arene)Ru(SAr)2 (2, Ar = 2,6-C6H3Me2 = Xyl; 3, Ar = 2,4,6-C6H2(CHMe2)3; arene = C6H6 (a), arene = p-MeC6H4(CHMe2) = p-cymene (b), arene = C6Me6 (c)) have been prepared by treatment of [(η6-arene)RuCl2]2 (1) with the corresponding sodium arenethiolate in methanol. Reaction of 2b with disodium of 1,2-benzenedithiolate (=S2C6H4) led to a mixture of monomer and dimer complexes (η6-p-cymene)Ru(S2C6H4) (4b) and [(η6-p-cymene)Ru(S2C6H4)]2 (5b) in solution. A complex (η6-C6Me6)Ru(S2C6H4) (4c) was predominantly monomeric, revealed by a crystal structure analysis of 4c. All these monomeric complexes show intense blue color of the LMCT band due to the donation from the filled S(pπ) orbital to the empty Ru(dπ*) orbital, which stabilizes coordinatively unsaturated ruthenium(II). The structures of these complexes are characterized by NMR and mass spectra and elemental analysis in addition to the X-ray crystal structure determinations of 2a,b, 3c, and 4c, indicating the two-legged piano stool geometry. The newly prepared 16-electron complexes react with π-accepting molecules such as isocyanide, carbon monoxide, and trialkylphosphine. Treatment of 2b with an excess of tert-butyl isocyanide resulted in the release of the p-cymene ligand to give trans-Ru(SXyl)2(CN t Bu)4 (8). Similarly, reaction of 5b with an excess of tert-butyl isocyanide afforded cis-Ru(S2C6H4)(CN t Bu)4 (10), while reaction of 5b with 6 equiv of tert-butyl isocyanide gave a binuclear complex [Ru(S2C6H4)(CN t Bu)3]2 (11). In the case of more strongly coordinating C6Me6 derivatives 2c and 4c, one molecule of tert-butyl isocyanide can coordinate to the ruthenium atom, resulting in the formation of (η6-C6Me6)Ru(SXyl)2(CN t Bu) (9c) and (η6-C6Me6)Ru(S2C6H4)(CN t Bu) (12c), respectively. Reactions of 5b and 4c with an excess of triethylphosphine afforded (η6-p-cymene)Ru(S2C6H4)(PEt3) (13b) and (η6-C6Me6)Ru(S2C6H4)(PEt3) (13c), respectively. In the carbonylation, 2b gave a binuclear carbonyl complex (CO)3Ru(μ-SXyl)3Ru(CO)2(SXyl) (14), while the carbonylation of the C6Me6 complex 2c afforded (η6-C6Me6)Ru(SXyl)2(CO) (15). Versatile reactivity of 16-electron ruthenium(II) thiolate complexes is thus demonstrated.

Poststroke patients with functional constipation, assessed by the Rome III criteria, from 6 hospitals were recruited in a study on the effects of the traditional Japanese medicine Daikenchuto (DKT) on constipation. Thirty-four patients (17 men and 17 women; mean age: 78.1 ± 11.6 years) were randomly assigned to 2 groups; all patients received conventional therapy for constipation, and patients in the DKT group received 15 g/day of DKT for 4 weeks. Constipation scoring system (CSS) points and the gas volume score (GVS) (the measure of the intestinal gas volume calculated from plain abdominal radiographs) were recorded before and after a 4-week observation period. The total score on the CSS improved significantly in the DKT group compared to the control (P < 0.01). In addition, scores for some CSS subcategories (frequency of bowel movements, feeling of incomplete evacuation, and need for enema/disimpaction) significantly improved in the DKT group (P < 0.01, P = 0.049, and P = 0.03, resp.). The GVS was also significantly reduced in the DKT group compared to the control (P = 0.03). DKT in addition to conventional therapy is effective in treating functional constipation in poststroke patients. This study was a randomized controlled trial and was registered in the UMIN Clinical Trial Registry (no. UMIN000007393).

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A total of 1,835 Yersinia spp. were isolated from 925 (60.5%) of 1,530 wild mice and from 139 (79.9%) of 174 moles living in mountainous areas of eastern Shimane Prefecture, Japan. The Yersinia spp. included 1,106 Yersinia enterocolitica, 26 Y. enterocolitica-like, 176 Yersinia mollaretii, 149 Yersinia frederiksenii, 70 Yersinia intermedia, 231 Yersinia kristensenii, 5 Yersinia aldovae, and 72 Yersinia pseudotuberculosis. Human pathogenic Y. enterocolitica was not isolated. Y. pseudotuberculosis was divided into 10 virulent 40-to 50-MDa plasmid-positive (P+) strains (serotypes lb, 4b, and untypeable) and 62 plasmid-negative (P-) strains (serotypes lb, 2b, 2c, 4a, 5a, 5b, 6, 7, and untypeable). P+ strains of serotypes lb (two strains), 4b (seven strains), and untypeable (one strain) were isolated from nine Apodemus speciosus and one Apodemus argenteus. The isolates of Yersinia spp. were more frequently detected in newborn mice and during the breeding season. The P+ Y. pseudotuberculosis strains were recovered at less than 104 cells per g of the cecal contents. Thus, the prevalence of Yersinia spp. in small wild animals depends on the newborn animals born during the cold months, and wild mice in mountainous areas are important reservoirs of Y. pseudotuberculosis.