From the fronds of Polystichum tripteron (KUNZE) P_R. a new norcarotenoid glycoside was isolated and shown to be (R, , R)--hydroxy-megastigma-, -dien-3-one--O-β-D-glucoside. The fronds of Dennstaedtia wilfordii (MOORE) CHRIST. contain the same glucoside.

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One method currently being considered for the disposal of high level radio-active waste is burial in the seabed. When a hot object is buried in soil, the temperature of the soil adjacent to the object is raised and there is transient heat flow away from the object. The rise in the temperature of the soil causes excess pore pressures to be generated and transient pore water diffusion also takes place. A finite element formulation of the coupled heat flow and consolidation problem is presented. The computer implementation of this formulation is found to compare favourably with analytical solutions based on the same physical principles.

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2-Benzyl--chloro--mercapto-3 (2H)-pyridazinone (1) was heated in ethanol under reflux for 10 hours to form concurrently 2, -dibenzyldipyridazo [, - : ', '-]-1, -dithiin-1, (2H, H)-dione (Ia) (57% in yield) and 2, 8-dibenzyldipyridazo [, - : ', '-]-1, -dithiin-1, (2H, 8H)-dione (IIa) (14% in yield). Assignment of the two products to the corresponding structures is established by their physico-chemical constants and chemical behaviors. The concurrent formation of the dipyridazo [, - : ', '-]-1, -dithiin-1, (2H, H)-dione and the -1, (2H, 8H)-dione were observed in, not only heating -chloro--mercapto-3 (2H)-pyridazinones (1-3) in polar solvent, but warming -mercapto--chloro-3 (2H)-pyridazinones (-) in the presence of potassium carbonate in DMF. For the interpretation of the reaction, keto-thioketo carbenes as active intermediate species and a reversible interconversion among them are suggested on the basis of the fact that there was nonexistence of an equilibrium between the two compounds, such as Ia and IIa, under the reaction condition and a trapping keto-thioketo carbene species as 2-phenylimino--benzylpyridazo [, -d]-1, 3-dithiol- (H)-one (IVa) (14% in yield) along with the major products, (Ia) and (IIa), was furnished by warming 1 with phenylisothiocyanate in the presence of triethylamine in dry benzene. On the contrary, participation of a reversible interconversion between Ia and IIa, to a considerable extent, with the concurrent formation of them in the case of benzylation of either Ib or IIb, by warming with benzylchloride in the presence of potassium carbonate in DMF at 80°, might not be neglected, because an attempted approach to an equilibrium between Ia and IIa in a similar reaction condition except the use of benzylchloride realized, whereas non-existence of an equilibrium between Ib and IIb in the similar reaction condition was observed.

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The ability of Climacodon septentrionalis to immobilize and kill a mycophagous nematode (Aphelenchoides sp.) in vitro is described for the first time. Two isolates produced droplets (20–45 μm in diameter) that formed at the apices of tall, stalked, and branching secretory cells (700–1,500 μm tall). On 2% modified malt extract agar, nematodes became enveloped in the droplets, which restricted their ability to move and resulted in complete immobilization and death within several hours of contact. The rate of decomposition of the nematodes varied considerably, with most individuals persisting for weeks whereas others were degraded within several days and appeared to be colonized by dense hyphal growth. This study provides the first documentation of a non-agaricoid fungus producing secretory cells that are able to immobilize nematodes.

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Nアルキル3,:,10-ペリレンテトラカルボン酸モノアンヒドリド=モノイミド[a～]と芳香族アミン(アニリン,p-トルイジン,p-アニシジン,3,-キシリジン,-アミノナゾベンゼン,およびo-フェニレンジアミン)を縮合して非対称型3,:,10-ペリレンビス(ジカルボキシミド)誘導体-N-アルキル-N'-アリール-3,:,10-ペリレンビス(ジカルボキシミド)(〔a～〕,〔a～〕,〔a～〕,〔8a～〕,〔a～〕,および〔10a～〕)を合成した. これらの各誘導体はすべて赤色系の色相を示し, 顔料試験の結果N-ブチル-N'-アリール-3,:,10-ペリレンビス(ジカルボキシミド)(たとえば〔〕や〔〕)がとくにすぐれた耐光性を示した.

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Two new partially saturated tricyclic ring systems, , a, , 8, , 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (3a and 3), and -thiepins (a and ) were synthesized. Compounds a and were desulfurized to give a pair of isomeric 2-methylbenzoylcyclohexanes (10a and 10). Deuterated a and (11a and 11) were prepared starting from butadiene- (12). The stereochemical features of 3a (trans), 3 (cis), a (trans) and (cis) are compared with those of 10a, 10, 11a and 11 on the basis of proton nuclear magnetic resonance data.

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The main objective of this paper is to compare safety factors obtained from Morgenstern-Price, Janbu and Spencer methods with the factors calculated from the modified variational approach (Leshchinsky and Huang, 1992a). Such comparison is essential since there is no mathematical proof that the variational analysis indeed yields a minimum and thus, physically produce significant results. The safety factors compared well, indicating the variational analysis is on a par with acceptable existing rigorous methods. Availability of a user-friendly computer code may make the variational analysis useful to practicing engineers. However, its greatest potential at the moment is in 3-D applications; i.., unlike other methods, its extension to 3-D is straightforward.

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-Amino--mercapto-1, 3-dimethyluracil (2) was prepared by the treatment of , -diamino-1, 3-dimethyluracil (1) with liquid H₂S and pyridine in a sealed steel tube at 60° for 20 h. Thiazolo[, -d]pyrimidinediones 3a, were obtained from 2 by cyclization with HCO₂H and AcOH.Under stringent conditions, however, 1 was converted into the , -dihydrodipyrimido[, - : ', '-][1, ]thiazine derivtive a.The structure of a was confirmed by spectral (nuclear magnetic resonance and mass spectra) data and by comparison with a sample which was prepared from 2 and -hydroxy-1, 3-dimethyluracil.Benzylation of a gave 1, 3, , -tetramethyl--benzyl (or p-bromobenzyl)-, -dihydrodipyrimido[, - : ', '-][1, ]thiazine-2, , , 8-(1H, 3H, H)-tetrone (, ) and 1, 3, , -tetramethyl--benzyl (or p-bromobenzyl)-, -dihydropyrrolo[3, 2-d : , -d']dipyrimidine-2, , , 8-(1H, 3H, H)-tetrone (a, ).

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Agaricus blazei is an important fungus for producing bioactive compounds. There are some reports of polysaccharides and steroid derivatives from the fruiting bodies of A. blazei. However, the chemical examination of the secondary metabolites of the cultured mycelia of this species has not been reported. Eight compounds, an unprecedented skeleton have been isolated from the cultured mycelia of A. blazei. The structures of the novel compounds each named blazeispirols A (1), (2), (3), D (), () X(), Y () and Z (8) were confirmed by extensive 1D and 2D NMR spectral data and X-ray analysis. Blazeispirols A (1), (2), (3), D () and () were des-A-ergostane type compounds having spiroacetal structure as a side chain. Blazeispirols X () and Y () were determined to be (20S, S, 23R, 24S)-1 (10→) abeo-14β, :, 25-diepoxyergosta-,,,11-tetraene-3α,23-diol and (20S, S, 23R, 24S)-14β,:,25-diepoxy-,23-dihydroxyergosta-,,11-triene-3,-dione by comparison of extensive 1D and 2D NMR spectral data with that of blazeispirol A. The biosynthesis of blazeispirol A was investigated by feeding ^<13>-labeled acetates and methionine to the growing cultures of A. blazei. The labeling patterns of 1 derived from singly and doubly ^<13>-labeled acetates were consistent with that of ergosterol reported previously except for the A-ring and then ^<14>-labeled ergosterol was incorporated into blazeispirol A. Taking the structures of blazeispirols Z and D into consideration, it can be assumed that blazeispirol A is biosynthesized from ergosterol by the cleavage of -, - and -1, -10 bonds on retro aldol condensation and Michael reaction via such as intermediate A as shown in Fig. . A large number of ergostane-type steroids have been isolated from many fungi. However, blazeispirol A is the first example of a naturally occurring des-A-ergostane-type steroid including a spiroacetal structure moiety as a side chain.

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The apogalanthamine analogs - and -bromo-, , , 8-tetrahydrodibenz [, ] azocines (a and a) and their methylenedioxy derivatives ( and ) were prepared by photolysis of the hydrochlorides of the respective N-benzyl-β-phenethylamines (8a, and a, ) substituted with both iodine and bromine atoms. The dibenz [, ] azocines a and were also obtained by thermal syntheses from the biphenyl compounds 17a and 17, respectively.

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Circuit techniques to enhance the linearity of input-voltage-to-current (V/I) conversion and to increase the output impedance of a current source by compensating for the low intrinsic gain of a transistor were introduced to realize a high-frequency operational transconductance amplifier (OTA) for a low supply voltage using sub-100-nm CMOS processes. Applying these techniques, a MOS th-order Gm- linear-phase low-pass filter (LPF) was realized using a 65nm CMOS process. A simplified biquad LPF that can serve as a component of a th-order LPF was newly developed by replacing OTAs with resistors. As a result, the -3dB frequency bandwidth, group delay ripple, 3rd-order distortion, and 3rd-order input intercept point (IIP3) were 200MHz, 2.2%, ≤ -55dB with a 100MHz input, and +10.3dBm, respectively, all with a ±0.1Vp-p input signal at each input terminal in the pseudodifferential configuration. The LPF including an output buffer dissipated 60mW in the case of a 1.2V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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Stereoselective synthesis of , - and , Z-β-ionylideneacetaldehydes was accomplished from the β-ionone tricarbonyl iron complex, and the latter was converted to Z-retinoic acid.

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Eight new sterols, , 8α-epidioxy-(, 24R)-23-methylergosta-, -dien-3β-ol (1), 3β, , -trihydroxy-(, 24R)-23-methylergosta-, -dien--one (2), 3β, , -trihydroxy-(24S)-ergost--en--one (3), 3β, , , 14α-tetrahydroxy-(, 24R)-ergosta-, -dien--one (), (, 24R)-ergosta-, -diene-3β, , , -tetrol (), , -epidioxy-3β-hydroxy-(, 24R)-ergosta-, -dien--one (), , -epidioxy-3β-hydroxy-(24S)-ergost--en--one () and , -epoxy-(, 24R)-ergosta-8, -diene-3β, , 14α-triol (8), have been isolated from five edible mushrooms, Lentinus edodes, Flammulina velutipes, Hypsizigus marmoreus, Pleurotus ostreatus and Pholiota nameko together with fifteen known ones (-23), of which two (16 and 17) are reported for the first time from a fungal source. The structures of these new compounds were elucidated on the basis of their spectral data.

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