Axially Chiral Borinic Acid Catalysts: Design, Synthesis, and Application in Alkylative Desymmetrization of 1,2-Diols.

A novel chiral borinic acid (CBA), an organocatalyst possessing a binaphthyl skeleton, was designed and synthesized. The synthesis of CBA was achieved with a 72% yield in four steps starting with optically pure 1,1'-bi-2-naphthol. The asymmetric catalytic activity was investigated in the desymmetrization of meso-1,2-diol.

Double isomerization/cycloisomerization/aromatization of 1-(allyloxy)-2-(cyclopropylmethyl)benzenes to give 2-ethyl-3-isopropylbenzofurans using a multitasking single rhodium catalyst.

Multitasking single-catalyst systems that allow multiple chemical transformations within a single reaction vessel are important for the development of eco-compatible chemistry. Here, we have developed a rhodium-catalyzed system that transforms 1-(allyloxy)-2-(cyclopropylmethyl)benzene derivatives to 2-ethyl-3-isopropylbenzofurans via double isomerization/cycloisomerization/aromatization.

Iridium-Catalyzed Isomerization/Cycloisomerization/Aromatization of N-Allyl-N-sulfonyl-o-(λ1-silylethynyl)aniline Derivatives to Give Substituted Indole Derivatives.

We have developed a one-iridium-catalyst system that transforms N-allyl-N-sulfonyl-2-(silylalkynyl)aniline derivatives, which are 1,7-enynes in which both multiple bonds have a heteroatom, to the corresponding substituted indole derivatives via isomerization/cycloisomerization/aromatization. This strategy provides an atom-economical and straightforward synthetic approach to a series of valuable indoles having vinyl and silylmethyl groups at the 2- and 3-positions.

Iridium-Catalyzed Intramolecular Cycloisomerization between Functionalized Alkyne with Aryl Vinyl Ether: Synthesis of 2-Vinyl-3-functionalized Methylbenzofurans.

We have developed cycloisomerization between an aryl vinyl ether and a functionalized alkyne, such as silylalkyne, to give 2,3-disubstituted benzofuran derivatives using [IrCl(cod)]2, PCy3, and NaBArF4. This catalyst system not only catalyzes the above cycloisomerization but also isomerize a terminal olefin to give an aryl vinyl ether.

Direct synthesis of dialkylarylvinylsilane derivatives: metathesis of dialkylaryl-iso-propenylsilane and its application to tetracyclic silacycle dye synthesis.

The metathesis of dialkylarylvinylsilane, which has not been accomplished to date, is achieved using dialkylaryl-iso-propenylsilane as a substrate. In addition, we discovered that the reason why the metathesis of a ruthenium carbene complex and dialkylarylvinylsilane is difficult is the formation of a carbide complex.

The efficacy of mizoribine for the treatment of rheumatoid arthritis and its correlation with renal function.

OBJECTIVES: To evaluate the correlation between the efficacy of mizoribine (MZR) and the factors that might effect MZR concentration: renal function and dosage and administration of MZR in patients with rheumatoid arthritis (RA). METHODS: The efficacy of MZR treatment was prospectively evaluated in 97 RA regardless of dosage, at the 14 participated institutions. The Disease Activity Score 28-CRP3 was used to assess RA activity. The renal function was evaluated based on the serum creatinine and serum cystatin-C (Cys-C). The patients were followed up for 24 weeks. RESULTS: The patients with a mean age 66.2 years included 18 male. The renal function assessment showed increased creatinine in 16.4% of patients and increased Cys-C in 54.5%, suggesting the higher sensitivity of Cys-C to detect impaired renal function than creatinine. In patients with good or moderate response according to the European League against Rheumatism classification criteria, the Cys-C was significantly higher compared with those with no response. MZR treatment was significantly more effective in patients with an arithmetic product of the single MZR dose used and Cys-C of 179 or more. CONCLUSIONS: The efficacy of MZR may increase in proportion to its single dose, or increased Cys-C level in patients with impaired renal function.

Follow-up study of ankle arthrodesis in severe hind foot deformity in patients with rheumatoid arthritis using an intramedullary nail with fins.

We report herein a retrospective study of 25 cases of ankle arthrodesis performed in 23 patients with rheumatoid arthritis (RA) using an intramedullary nail with fins, developed in 1994. Surgical treatment, postoperative management, and clinical evaluation are described. Clinical evaluation, at an average follow-up period of 7 years 1 month, was based on foot disease scores from the Japanese Orthopedic Association; we compared these scores pre- and postoperatively, and during follow-up. These parameters showed a significant difference between preoperation and the follow-up period. However, instability only significantly improved when compared between pre- and postoperation. Arthrodesis using an intramedullary nail with fins was effective for the treatment of severe deformity of the hind foot. Nonunion was not observed and no remarkable changes of the Chopart joint were recognized between preoperation and the follow-up period. In our series, delayed wound healing was recognized in 6 of 25 joints. However, infection or neuropathy and other complications were not found. Arthrodesis using an intramedullary nail with fins is a viable treatment option for severe deformity of the hind foot in RA patients, because nonunion was not recognized and the clinical results over an average 7-year follow-up period were good or satisfactory.