Photo-initiated bromination of octakis(1,1,2-trimethylpropyl)octasila- cubane with tetrabromomethane

Bromination reactions of octasilacubane via radical intermediates are demonstrated. In the absence of oxygen, UV-light irradiation of octakis(1,1,2-trimethylpropyl)octasilacubane (1) with tetrabromomethane in benzene resulted in the formation of only exo,exo-4,8-dibromoctakis(1,1,2-trimethylpropyl)tetracyclo[3.3.0.0^2,7.0^3,6]octasilane(2). However, in the presence of oxygen, the reaction of 1 with tetrabromomethane took place without irradiation, producing 2 and a novel type of the monooxidation product, dibromooxahomosecocubane (3). For the formation of these products, an electron-transfer mechanism involving successive cleavage of the Si–Si bonds, followed by skeletal rearrangement is proposed.     

Development of a highly cardioselective ultra short-acting beta-blocker, ONO-1101.

A novel, highly cardioselective ultra short-acting beta-blocker, ONO-1101, has been developed for application in the emergency treatment of tachycardia and better control of heart rate in surgery. This agent is approximately nine times more potent in beta-blocking activity in vivo and eight times more cardioselective in vitro than esmolol. This beta-blocking drug has a short duration of activity, enabling rapid recovery after cessation of administration if side effects occur. It can be used safely in patients suffering from acute heart disease and represents a major therapeutic advance in the treatment of heart disease.     

Diastereoselective addition of alcohol to diastereotopic silylenes

The successful example of diastereoselective addition of alcohol to diastereotopic silylenes is reported.     

Improved apparatus for solid-liquid multi-stage counter-current extraction

An improved apparatus for solid-liquid multi-stage counter-current extraction (SLME) was developed. The apparatus has a set of 24 extraction vessels. Each extraction vessel unit is composed of a piston-cylinder in which the solid phase is placed, and a cup-cylinder in which the liquid phase is set. Of the 24 extraction vessels, 20 were used for the separation stage, and the other 4 were used for the back-extraction stage. (+/-)-Troger's base was selected as a racemic model compound for the continuous enantioseparation by the apparatus, and a cellulose derivative was used as the chiral separator. After 50 cycles of the operation (in 9 h), 0.1 g of (-)-enantiomer (85% in purity) was recovered from the solid phase by back-extraction with ethanol, whereas 1.1 g of (+)-isomer (75% in purity) was collected from the liquid phase (ethanol).     

Two countably compact topological groups: One of size and the other of weight without non-trivial convergent sequences

E. K. van Douwen asked in 1980 whether the cardinality of a countably compact group must have uncountable cofinality in . He had shown that this was true under GCH. We answer his question in the negative. V. I. Malykhin and L. B. Shapiro showed in 1985 that under GCH the weight of a pseudocompact group without non-trivial convergent sequences cannot have countable cofinality and showed that there is a forcing model in which there exists a pseudocompact group without non-trivial convergent sequences whose weight is . We show that it is consistent that there exists a countably compact group without non-trivial convergent sequences whose weight is .

     

Some properties of minimal solutions for a fuzzy relation equation

Some properties of the solution set and minimal solutions of a fuzzy relation equation are considered. In this paper, we show the necessary and sufficient condition for existence of a minimal solution of a finite fuzzy relation equation defined on infinite index sets.     

A model of a general parimutuel system: Characterizations and equilibrium selection

We formulate a model of a parimutuel system which considers a horse race with two horses. In our model, the raceholder offers a rate of his total betting revenue in the first stage. In the second stage each bettor simultaneously decides whether he bets one unit of money on one horse or he withdraws, according to his win predictions for each horse. We assume that all bettor's predictions are different and are common knowledge. We define some types of equilibria in the second stage game and give necessary and sufficient conditions for their existence. One equilibrium is a selected as a solution for the second stage game. We also define a solution for the whole game by using this result. Finally, we analyze the relation between the solution and variance for the bettor predictions.We thank to Prof. Okada, A. and Ikebe, Y. for helpful discussions. Special thanks are due to an anonymous referee for very grateful comments.