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This report describes the total synthesis of the complex, oxygenated tetracyclic alkaloid, lyconesidine B. The key synthetic challenge involves diastereoselective generation of a decahydroquinoline ring with a quaternary carbon at the angular position via domino cyclopropanation, ring-opening, and reduction. Another crucial step is the domino ene-yne metathesis involving a quaternary ammonium ion, leading to the construction of a decahydroazaazulen framework.

The upper fragment of spirolides A and B, which are marine phycotoxins that exhibit strong antagonistic activities on nicotinic acetylcholine receptors, was constructed. The functionalized cyclohexene in spirolides was stereoselectively synthesized from the bicyclic lactone, which could be readily accessed by the Lewis acid template-catalyzed asymmetric Diels-Alder reaction of the pentadienol and methyl acrylate.

This report describes the total synthesis of the complex, oxygenated tetracyclic alkaloid, lyconesidine B. The key synthetic challenge involves diastereoselective generation of a decahydroquinoline ring with a quaternary carbon at the angular position via domino cyclopropanation, ring-opening, and reduction. Another crucial step is the domino ene-yne metathesis involving a quaternary ammonium ion, leading to the construction of a decahydroazaazulen framework.

A transition-metal-catalyzed cyclopropanation followed by ring opening was investigated for the synthesis of octahydroquinolines 4 and decahydroquinolines 5 having a quaternary carbon center at the angular position, which are core structures of the fawcettimine-type alkaloids. A tandem reaction was also established for the synthesis of decahydroquinolines 5 and the tricyclic compound 6 through an iminium ion intermediate, readily produced by acidic treatment of cyclopropane 2.

The phenomenon known as Toms effect can impart viscoelasticity to a water flow when a small amount of water-soluble polymer is added. The resulting viscoelastic fluid generates viscoelastic stress in the flow, dramatically reducing the turbulent stress. In this study, the spatial distribution of velocity is measured using a stereo-PIV method in the streamwise-spanwise plane parallel to the wall. Modification of the near wall turbulence by the polymer solution blown slowly from a permeable wall was investigated by analyzing the velocity distribution acquired by stereo-PIV measurements. Experimental results reveal that streamwise local mean velocity decreases as the dosed polymer concentration increases. The skewness factor at this height shifts from 0 to positive by adding the polymer, which indicates intensified turbulent coherent structure. Moreover, the spatial two-point correlation function calculated from streamwise velocity fluctuations maintains its high correlation with the streamwise direction. It is consistent with the finding from the instantaneous velocity distribution, which shows that the flection of low-speed streaks is suppressed. Next, it is revealed that the normal velocity at the wall for low-speed fluid is decreased dramatically by polymer additives. Moreover, applying the quadrant analysis, it is confirmed that ejection events are suppressed with decreasing normal velocity at the wall. Suppression of ejection motion affects to the turbulence in the log law layer. We conclude that this is one reason that turbulence is suppressed in a wide range of the shear layer by polymer additives present only in the vicinity of the wall.

Our first fuel cell prototype with a novel Au-Pd-Pt catalyst successfully demonstrated power generation. In order to reduce amount of platinum group metals and obtain high CO tolerance, electrochemical atomic layer depositions of Pd and Pt were applied on the porous Au. 5 ML Pd and sub-ML Pt deposition was attempted and amounts of Pd and Pt were electrochemically estimated to be 125 μg/cm2 and 6 μg/cm2, respectively. No catalyst poisoning to 100 ppm CO was observed during the power generation. Though the peak power was poor around 100 mW/cm2, results were satisfying for the first prototype.