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Structures of the antifungal antibiotics, ezomycins B1 (1), B2 (21), C1 (3), C2 (4), D1 (5) and D2 (6), were elucidated by degradative and spectrometric studies. Compound 3 was found to be the α-anomer of 1 and 4 was that of 2. Compounds 2, 4 and 6 were easily interconvertible under weak acidic conditions.

On hydrolysis with Dowex 50W, ezomycin A1 (1) C26H40N8O16S gave ezomycin A2 (2) C19H28N6O13 and l-cystathionine (3) as main products. Further acid hydrolysis of 2 afforded an amino uronic acid named ezoaminuroic acid (5), 3-amino-3,4-dideoxy-d-xylohexopyranuroic acid, and cytosine. Ezoaminuroic acid, l-cystathionine and cytosine were found to constitute ezomycin A1.

The presence of an auxin synergist was confirmed in the neutral fraction of extracts from peanut plants (Arachis hypogaea L.). The main component resposible for the activity was established as stigmasteryl-β-D-glucoside. It promoted markedly the elongation of Avena coleoptile segments induced by indoleacetic acid (IAA), but was only weakly active in the absence of IAA.

Three quinolone alkaloids were isolated from fresh leaves and fruits of Evodia rutaecarpa Hook. f. et Thoms. and were structurally elucidated as 1-methyl-2-pentadecyl-4(1H)-quinolone (I), 1-methyl-2-tridecyl-4(1H)-quinolone(dihydroevocarpine,II) and 1-methyl-2-undecyl-4(1H)-quinolone (III) on the basis of spectral measurement and synthesis.

Structures of the antifungal antibiotics, ezomycins B1 (1), B2 (21), C1 (3), C2 (4), D1 (5) and D2 (6), were elucidated by degradative and spectrometric studies. Compound 3 was found to be the α-anomer of 1 and 4 was that of 2. Compounds 2, 4 and 6 were easily interconvertible under weak acidic conditions.

Rhodotorucine A, which induces mating tube formation in Rhodospridium toruloides, was found to be a novel peptide composed of eleven amino acid residues with a lipophilic group at the C-terminus. The amino acid sequence of the peptide was determined by Edman degradation and enzymatic hydrolyses. The C-terminus of rhodotorucine A was revealed to be S-farnesylcysteine by proton magnetic resonance, mass spectrometry and chemical synthesis. We proposed the following structure for rhodotorucine A. H-Tyr-Pro-Glu-Ile-Ser-Trp-Thr-Arg-Asn-Gly-Cys(S-farnesyl)-OH.

Effects of hydrofluorene and hydrophenanthrene compounds derived from dehydroabietic acid on the second leaf sheath growth of rice seedlings were examined in the presence and absence of gibberellin A3(GA3). In the absence of GA3, nineteen compounds at 100 ppm inhibited more than 20% the growth of normal rice seedlings. In the presence of GA3 (1.5 ppm) with dwarf rice seedlings, nine compounds at 500 ppm suppressed the elongation caused by the hormone, and a compound was slightly promotive. Then, three compounds were selected and subjected to the bioassay under various conditions.

From the antifungal ezomycin complex produced by a strain of Streptomyces were isolated six new components named ezomycins B1, B2, C1, C2, D1 and D2. They are novel pseudouridine-type C-C nucleoside antibiotics, of which B1 is the most active.

We have determined the complete amino acid sequence of 4K-PTTH-II, one of three forms of the M r 4400 prothoracicotropic hormone of the silkworm Bombyx mori , active to brainless pupae of Samia cynthia ricini . Like vertebrate insulin, it consists of two nonidentical peptide chains (A and B chains). The A chain consists of 20 amino acid residues. The B chain is a mixture of four microheterogeneous peptides, two of which consist of 28 residues, and the other two, of 26 residues. 4K-PTTH-II has considerable sequence homology (40%) with human insulin, and it resembles porcine relaxin both in the carboxyl-terminal cysteine residue of the A chain and in the amino-terminal pyroglutamic acid residue of the B chain. The identical distribution of the six cysteine residues also indicates that 4K-PTTH-II belongs to the insulin family.

Stress relaxation of sulphur-cured natural rubbers of different crosslinked structures was investigated in an atmosphere containing variable amounts of oxygen. At high temperature, even very low contents of oxygen strongly affected the degradation of these vulcanizates. The stress relaxation of each vulcanizate was analysed in relation to the sol fraction and the swelling of sample degraded under the same condition. The scission mechanism of the vulcanizates depended on the quantity of oxygen in the atmosphere. Under nitrogen, the scission occured mainly near the crosslink site in all the samples. However, in the case of their being small amounts of oxygen present it took place near the crosslink site in the initial stages of degradation and then along the main chain at the later stages. In the atmosphere of comparative high oxygen content, the degradation seemed to result from the oxidative scission along the main chain. The degradation mechanisms of sulphur-cured natural rubbers were also discussed.

1. There was no difference of stress relaxation, either in air or in nitrogen, between DCP cures (Sample 1) and irradiation cures (Sample 2). This suggests that these vulcanizates have the same physical and chemical structures. In air Samples 1 and 2 underwent random scission of only the main chain. 2. In the case of irradiation-TMTD cures (Samples 4 and 5), the stress decay was also based on oxidative scission of the main chain. The number of moles of main chain scission, qm(t), was independent of the ratio ρ (of Nc(0)) based on the carbon—carbon bonds to Nm(0) based on the mono- and disulfide links). However, qm(t) was larger than that of Sample 2. The oxidative scission of the main chain seemed to be accelerated by mono- and disulfide. It was found from comparison of Samples 4 and 5 that TMTD cures (Sample 3) underwent random scission on the main chain. The stress relaxation in nitrogen for Samples 3, 4, and 5 was due to thermal scission of the crosslink. 3. The stress relaxation, either in air or in nitrogen, of accelerated-sulfur-cures (Sample 6) and irradiation-sulfur cures (Samples 7 and 8) was expressed by the sum of two exponential terms. The stress relaxation in air of Samples 6, 7, and 8 could be explained by the interchange reaction of polysulfide links and the random scission on the main chain. The stress decay in nitrogen of these vulcanizates was based on both interchange of polysulfide links and thermal scission of crosslinks. The rate of the interchange reaction in air was very closely consistent with that in nitrogen. 4. The apparent activation energy of oxidative scission of the main chain was about 21 kcal/mol for Samples 2, 6, 7, and 8 and 27 kcal/mol for Samples 3, 4, and 5.

After twelve steps of purification, a peptidyl factor named rhodotorucine A*1 was isolated in pure form from a culture filtrate of A type cells of Rhodosporidium toruloides. Rhodotorucine A induced the mating tube formation in a cells, opposite mating type cells of the yeast, at a concentration of 8 ng/ml. A factor in the previous papers is now renamed rhodotorucine A.

Rhodotorucine A is a lipophilic undecapeptide having a novel amino acid, S-farnesyl-cysteine, at the C-terminus. Sulfonium salt formation of rhodotorucine A and subsequent hydrolysis afforded trans-trans-farnesol, trans-nerolidol and α-bisabolol. Thus, the geometry of the side chain of S-farnesylcysteine was established unambiguously as all trans. The reaction mechanism was also discussed.

Two lignans were isolated from leaves of Magnolia kobus DC. as growth inhibitors on silkworm larvae and structurally elucidated as sesamin (I) and kobusin (II) which has been hitherto unknown.

A new alkaloid named stemospironine (I) was isolated together with stemofoline (II) as the main insecticidal constituents of leaves and stems of Stemona japonica Miq. The absolute stereostructure of I has been determined by X-ray crystallographic analysis. Stemofoline (II) showed a much stronger activity than I against silkworm larvae (Bombyx mori L.) by oral administration.

A simple procedure for partial purification of silkworm brain hormone starting with heads of Bombyx moths is described. The method is unique in that it can supply samples with a definite activity without chromatography and bioassay during the purification process. The titer of brain hormone in every batch is 30~40 Samia units/head (specific activity, 1~2μg/Samia unit). Some chromatographic behaviors of the hormone are also reported.

The effects of various enzymatic and chemical treatments on the biological activity of the partially purified PTTH are described. PTTH was inactivated by pepsin, trypsin and α-chymotrypsin. Leucine aminopeptidase and carboxypeptidase A did not affect the biological activity of PTTH, suggesting that N- and C-terminus are blocked. Treatments with chemical reagents suggest that the tryptophan residue and disulfide bond are essential for the activity, whereas the sulfhydryl group is not. Tyrosinase exerted no effects. Glycosidases, neuraminidase, and periodate oxidation did not affect the activity, suggesting that carbohydrates are not essential for the biological activity of PTTH.

Cinnzeylanine (1) and cinnzeylanol (2) were isolated from barks of Cinnamonum zeylanicum Nees (ceylon cinnamon). Chemical properties and NMR spectra of the both compounds are disccused in terms of their structures which were determined by the X-ray analysis and chemical reactions. When administered orally with artificial diet, both 1 and 2 killed larvae of silkworm, Bombyx mori L. at a dose of 16 ppm and inhibited larval ecdysis at 2~ 4 ppm.

A new compound was isolated from leaves of peanut. Its structure was determined as o-(malonylamino)benzoic acid on the basis of physicochemical evidences.

A new gibberellin C20H26O6, tentatively named “bamboo gibberellin”, was isolated from water extract of bamboo shoots (Phyllostachys edulis) through successive purification procedures: countercurren...

Some different results from previous reports on acid degradation and catalytic reduction studies of the three components were obtained. From gibberellin Al only gibberellin C and no gibberic acid were obtained. From gibberellic acid (namely gibberellin X and A3) only gibberic acid and no gibberellin C were obtained. In addition to this, some experimental results of gibberellin A on animal tissues were also, presented.

A new crystalline steroid conjugate was obtained by partial acid hydrolysis of asterosaponin A, a steroidal saponin from the starfish, Asterias amurensis . The structure of the conjugate was established as 5α-pregn-9(11)-ene-3β,6α-diol-20-one-3-sulfate ( 2 ) on the basis of elemental analysis, IR and PMR spectra measurement and chemical reaction. Solvolysis of compound 2 yielded 5α-pregn-9(11)-ene-3β,6α-diol-20-one. Oxidation with chromium trioxide-pyridine complex followed by solvolysis afforded a new steroid, 5α-pregn-9(11)-ene-3β-ol-6,20-dione, whose structure was deduced by the measurement of ORD curve and PMR spectra. Thus, the location of carbohydrate moiety in asterosaponin A has been assigned to 6α-hydroxy group of the steroid conjugate.

Helminthosporol, a metabolic product of Helminthosporium sativum, remarkably stimulated elongation of the second leaf sheath of rice seedlings of various varieties. It also stimulated the elongation of hypocotyls of cucumber seedlings. This substance did not have any effect on the growth of peas, tomato, sunflower and the dwarf mutants of maize. This substance did not have auxin-like activities.

In the previous papers(1)(2)(3) it was reported that several ω-(3, 4-dihydroxyphenyl) alkanoic esters and ω, ω'-bis-(3, 4-dihydroxyphenyl) alkanes were prepared and were found to have marked antioxydant activities. In the present paper, therefore, synthesis of ω-(2, 5-dihydroxyphenyl) alkanoic esters and ω, ω'-bis-(2, 5-dihydroxyphenyl) alkanes, the isomers of above compounds, were undertaken to search more effective antioxydants. 1) The synthesis of methyl γ-(2, 5-dihydroxyphenyl) butyrate (V): β-(2, 5-Dimethoxyphenyl) propionic acid (I) prepared by the treatment of hydroquinone dimethyl ether with succinic anhydride in the presence of AlCl3, was demethylated with HI to give β-(2, 5-dihydroxybenzoyl) propionic acid (IV). This was then reduced to γ-(2, 5-dihydroxyphenyl) butyric acid (III) by the CLEMENSEN reduction and was then esterified. 2) The synthesis of methyl e-(2, 5-dihydroxyphenyl) caproate (XIII): Hydroquinone dimethyl ether was condensed with polymeric adipic anhydride in the presence of AlCl3 to give δ-(2, 5-dimethoxybenzoyl) valeric acid (VIII). This acid was reduced by the CLEMENSEN reduction to give e-(2, 5-dimethoxyphenyl) caproic acid (X). The demethylation of (X) with HI gave e-(2, 5-dihydroxyphenyl) caproic acid (XI), which was esterified in the usual way. 3) The synthesis of 1, 6-bis-(2, 5-dihydroxyphenyl) hexane (XIV): Two moles of hydroquinone dimethyl ether were condensed with one mole of adipyl chloride in the presence of AlCl3 to give 1, 4-bis-(2, 5-dimethoxybenzoyl) butane (IX), which was reduced by WOLF-KISNER method to 1, 6-bis-(2, 5-dimethoxyphenyl) hexane (XIII) and was then demethylated. 4) The synthesis of 1, 10-bis-(2, 5-dihydroxyphenyl) decane (XVII): This compound was prepared in 'the same way as in (XIV), using sebacoyl chloride and hydroquinone dimethylether as starting materials. The antioxydant activities of these compounds will be discussed in the following paper. The authors wish to express their appreciation to Professor Dr. Y. SUMIKI for his guidance and advice.

Helminthosporol (H-ol) promoted the growth of light grown cucumber hypocotyls. The IAA-oxidase activity per dry weight of the hypocotyl of H-ol treated materials was less than that of controls. There was an inverse relationship between IAA-oxidase activity and H-ol induced elongation of the hypocotyl. However, when IAA-oxidase activity per plant was compared between H-ol treated materials and controls there was no essential difference. It is concluded that the apparent inhibitory effect of H-ol on IAA-oxidase activity is not directly related to the mechanism of H-ol action.

前報では, 完全網目構造を, ピラミッド型と仮定してその理論が扱われてきた。この報告では, 構造を無限完全網目構造と仮定し, 橋かけ点の切断後に表われる2x-merは応力には無関係であるが隣接するx-mer鎖の切断後には応力に対して有効鎖として挙動するという, より妥当な仮定を行ない, これらを考慮した改良理論を導いた。主鎖および橋かけ点近傍の切断が同時に起こる場合の理論をも導いた。

The functions of isoflavonoids and related compounds as well as of their degradation products in the allelopathy of red clover were investigated from chemical standpoint. Susceptibilities of red clover to isoflavonoids, related compounds and their degradation products were higher than those of various plants including white and alsike clovers, and contents of the isoflavonoids in red clover were extremely higher as compared with those in white clover and orchard grass. Inhibitory substances were isolated from the soil capable to cause “clover sickness,” but they were not isoflavonoids but phenolic acids considered to be originated probably in the formers. These acids were also obtained together with some kinds of isoflavonoids from the waste culture solution used for cultivation of red clover seedlings. Finally degradation process of isoflavonoids was followed up in neutral, acidic and alkaline solutions.