Chemo-and site-selective hydrosilylation of αor β-hydroxy amides using organocatalyst B(C 6 F 5 ) 3 and commercially available hydrosilanes is described. This transformation is operative under mild conditions and tolerates a wide range of functional groups. The reaction was applied for selective reduction of a specific amide group of the therapeutically important cyclic peptide cyclosporin A, demonstrating the potential usefulness of this catalytic method in late-stage structural transformations of drug lead molecules.

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We have devised a steering system in which the magnetic elastomer is used for the elastic members such as rubber bushings in the axle box suspension of railway vehicles. The magnetic elastomer is composed of magnetic particles and the elastomer such as synthetic rubber. This material is characterized by its hardness variation depending on the magnetic field. The axle box suspension using the magnetic elastomer is capable of varying the longitudinal stiffness. In straight sections, the application of this axle box suspension ensures running stability by increasing the longitudinal stiffness by means of applying a magnetic field. On the other hand, in curve sections, it improves curving performance by decreasing the longitudinal stiffness by means of turning off the magnetic field. We made test pieces towards the development of the magnetic elastomer for the steering bogie. In a characteristic test, we confirmed that the Young's modulus of the magnetic elastomer changes in the range of about five times depending on the presence or absence of the magnetic field. In addition, we simulated the vehicle model by applying the longitudinal stiffness change of the magnetic elastomer to the axle box of the bogie. We confirmed that this axle box was capable of reducing the average of the outer wheel lateral force in the circular curve section compared to that of the normal axle box.