Osamu Hara

Cladosporol, β-1, 3-glucan biosynthesis inhibitor, isolated from fungus, Cladosporium cladosporioides

Abstract Cladosporol ( 1 ) was isolated from culture filtrate of Cladosporium cladosporioides as a hyphal malformation inducer in Phytophthora capsici . Cladosporol was found to be a β-1, 3-glucan biosynthesis inhibitor and the structure of cladosporol was determined by spectroscopic analysis.

A highly stereoselective synthesis of Z-disubstituted olefin by O-assisted Still-Wittig rearrangement

Abstract In the Still-Wittig rearrangement, stannylated methyl ( E )-allylic ethers having an aliphatic side chain ( 1a-c ) exhibited the usual similar stereoselectivity, although the poor stereoselectivity was remarkably improved by the assistance of an alkoxy moiety on the alkenyl chain. A stannylated methyl (Z)-allylic ether bearing an alkoxy moiety on the alkenyl chain ( 1e ) also showed a high E selectivity as previously reported.

An Attempt to the Unified Description of Elementary Particles

An attempt is made to give a unified and a more POSItive definition of elementary particles by introducing a substance of higher level than them. This substance is named Urmaterie, and is assumed to be described by a non-local field proposed by Y ukawa. Various states of the internal motion of Urmaterie are classified by eigenvalues of a complete set of mutually commutative operators with respect to internal coordinates, two of which can be taken as the spin and the mass operators. Each eigenstate thus classified is assumed to correspond to the elementary particle of the present theory. In § 1, the present situation of the theory of elementary particles is analysed, and the phenomexad nological feature of the present theory and the necessity of introducing a substance of higher level to overcome it is stressed. In § 2, the spin and the mass operators are introduced. It is done according to the principle that ,the structure of elementary particles should determine uniquely the transformation properties of the wave functions under· Lorentz-transformations. The equations of motion of Urmaterie are then derived from korrespondenzmassig considerations and from the principie of reciprocity. In § 3, the eigenvalue and the eigenfunction of the mass operator is given in the simplest case when the Urmaterie field is assumed as scalar. In § 4, the relation of this Urmaterie field to the local field is discussed, and it is shown that, in the case of the scalar as before, the equation of motion of Urmaterie reduces to that of Fierz for eigenstates of the spin and the mass operators. In § 5, a qualitative discussion on the interaction of Urmaterie is given. In § 6, an extension to the case of spinor is discussed. It is shown that the existence of a new structure constant other than the spin and the rest mass inevitably follows. It is shown that this is interpretable as expressing the essential difference of the heavy and . light particles, and in its connection an attempt is made to deduce the conxad servation law of heavy particles. In § 7, the deductive perspective and the further outlook of the theory is brief! y given.

Synthetic studies on development of a novel macrolide ionophore: Configurational requirement of 16-membered macrodiolide for binding ability

Twelve synthetic 16-membered macrodiolides were prepared from racemic homononactic acid. The compounds which have an anti-relationship between the ether linkage of THF and the adjacent methyl showed the cation-binding ability. Macrodiolide 12 exhibited the ion selectivity for Li+.

On the universal Fermi interaction

SummaryIt is shown that, by introducing the interaction in the form of the interaction of Urmaterie, a substance of higher level than elementary particles, the universal Fermi interaction with the combinationf1(S−T+P)+f2(S−A−P), wheref2 andf2 are arbitrary constants, follows uniquely.RiassuntoSi dimostra che, introducendo l’interazione sotto forma di interazione dell’ «Urmaterie», sostanza di livello superiore a quello delle particelle elementari, ne consegue univocamente l’interazione universale di Fermi con la combinazionef1(S−T)+P)+f2(S−A−P), dovef1 ef2 sono costanti arbitrarie.

An Attempt of Generalizing the Hypothesis of Charge Independence, I --Selection Rule for the Decay Process--

An attempt is made of generalizing the hypothesis of charge independence to the weak interaction. The fundamental assumption is that the strangeness quantum number is not a scalar but the third component of an angular momentum vector in the charge space, and the sum of this new vector and the usual isotopic spin is conserved in all processes. The case when the usual charge independence holds is assumed to correspond to the special case when these two vectors art conserved separately. It is shown that this assumption leads, when combined with the composite hypothesis proposed by Markov and Sakata, to a consistent level scheme for hyperons and heavy. mesons, and moreover gives a new selection rule for the decay process which is essentially equivalent to /.dl/ =! recently suggested by many authors. It gives also other results which can be compared with experiments directly. Among them a preliminary discussion is given on a new selection rule expected in the annihilation of nucleon-antinucleon pairs. A comment on the b-field proposed by Yang and Mills is also given.