The gamma-ray spectrum and the conversion-electron spectrum are measured in the decay of the ^116mIn activity. Directional correlations are also measured for 818–1293 and 1097–1293 keV cascades. The M1-2 mixing ratio δ, and the 0-2 mixing ratio μ_k are obtained for 818.7 keV +→2₁⁺ transition to be δ=1.52−

0.22

+0.26, and μ_k≤

6

.1×10−

4

respectively. The

E

2 branching ratio

B

(

E

2;

2₂

+→0_g⁺):

B

(

E

2;

2₂

+→2₁⁺):

B

(

E

2;

2₂

+→0₁⁺) is determined to be 0.0158:1.0:

5

.86.

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Pironetin 1 (PA-48153C) is a novel unsaturated δ-lactone derivative isolated from the fermentation broths of Streptomyces species which shows immunosuppressive and plant growth regulating activities. Several total syntheses of 1 have been reported to date, but we show here a novel approach to 1 via a convergent route using our chiral building block, (1S,S,R)--hydroxybicyclo[.1.0]heptan-2-one . We dissected pironetin at C-C7 and employed the coupling of the epoxide 16 with the dithiane 25, which would be derived from , as a key step. The THP ether of was methylated and the following reduction gave an inseparable mixture of four diastereomers 8. After etherification, removal of THP group afforded separable isomers a and in a ratio of 13 to 1. The desired major isomer a was oxidized to ketone . Oxidation of via silyl enol ether with osmium tetroxide gave ketol 21 in quantitative yield. Reduction of cyclopropylketone moiety of 21 under Birch condition afforded a mixture of a and . The ketol moiety of a and was oxidatively cleaved with lead tetraacetate in benzene-methanol to give the single aldo-ester 23. Acetalization of 23 followed by reduction of ester group gave aldehyde 24. Introduction of C2-unit via Takai's protocol as -olefin formation followed by thioacetalization afforded the dithiane 25, as C7-C14 unit of pironetin. Meanwhile, the epoxide 16 as C1-C unit was prepared from known epoxy alcohol 3 in steps. Coupling reaction of two units, the dithiane 25 and the the epoxide 16, successfully gave the product with the whole skeleton 26 in high yield. Mercuric ion assisted hydrolysis of the thioacetal 26 gave ketol 27. Selective reduction of β-hydroxyketone 27 by Mori's method afforded and-diol 28a predominantly (: ). Finally, desilylation and oxidation with manganese dioxide afforded pironetin 1.

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Brassinolide analogues, (R, 23R, 24R)-2α, 3α, , 23-tetrahydroxy--homo-7-oxa--ergostan--one (24-epibrassinolide) (10) and (S, 23S, 24R)-2α, 3α, , 23-tetrahydroxy--homo-7-oxa--ergostan--one (), were synthesized from brassicasterol (3a) in five steps and with ca. 20% overall yield. The key steps are the direct formation of (, 24R)-3α, -cyclo--ergost--en--one () from brassicasterol mesylate (3), the acid-catalyzed rearrangement of to (, 24R)--ergosta-2, -dien--one (), and the Baeyer-Villiger oxidation of the tetrahydroxy -ergostan--ones 7 and 8.

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The phase diagrams of the Ni-Mo- and Ni-W- ternary systems in the region of less than 50mol% were constructed by thermodynamic calculation, based on the data obtained by thermodynamic measurement of the related materials. We found three ternary eutectic points and three or two ternary peritecto-eutectic points as follows:
:L (1365K, 71.mol%Ni-.0mol%Mo-.mol%)=(Ni)++
:L (1355K, 62.mol%Ni-2.mol%Mo-30.mol%)=++
:L (1445K, 42.0mol%Ni-30.mol%Mo-10.3mol%)=(Ni)+NiMo+
P₁:L (1812K, 34.mol%Ni-42.3mol%Mo-.8mol%)+MoB=+
P₂:L (1633K, 42.3mol%Ni-40.mol%Mo-17.3mol%)+Mo=+
P₃:L (1812K, 53.mol%Ni-33.7mol%Mo-12.8mol%)+Mo=NiMo+
:L (1622K, 51.0mol%Ni-31.mol%W-17.mol%)=(Ni)+W+
:L (1260K, 71.0mol%Ni-7.0mol%W-.0mol%)=(Ni)++
:L (1291K, 65.mol%Ni-.8mol%W-29.8mol%)=++
P₁:L (2115K, 23.8mol%Ni-43.1mol%W-33.1mol%)+WB=+
P₂:L (1657K, 48.mol%Ni-33.1mol%W-18.0mol%)+=W+
The calculated phase diagrams are expected to be useful for the development of new Ni-based heat-, corrosion- or wear-resistance alloys.

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We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MC3T3-1. Sixteen phosphate buffered saline (PBS), 8 boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MC3T3-1 cell differentiation. The enzyme activities were markedly induced by extracts of Tricholoma auratum, and we isolated the active compound from methanol extracts of this mushroom. Physical data for the isolated active compound were identical to those for (,24R)-ergosta-7,-diene-3β,,-triol (1). 1 induced ALP activities of MC3T3-1 cells and promoted cell proliferation. To investigate the relationships between the chemical structure and differentiation-inducing activity of the compound, ALP-inducing activities of MC3T3-1 cells by 1, ergosterol (2), ergocalciferol (3), cholesta-3β,,-triol (), 7-dehydrocholesterol () and cholecalciferol () were tested. The enzyme activities of MC3T3-1 cells were increased 3.0-fold by 10 μM 1 and 2.-fold by 10 μM . However, 2, 3, and did not induce MC3T3-1 cell ALP activity at 0.1—10 μM. These results suggested that the OH groups at C- and/or C- of 1 and played an important role in their differentiation-inducing activities on MC3T3-1 cells. Furthermore, 1 suppressed induction of MC3T3-1 cell apoptosis by serum starvation.

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This study aimed to determine the prevalence of fecal carriage of extended spectrum β-lactamase (ESBL) and/or plasmidic AmpC β-lactamase (pAmpC) producing Escherichia coli among dogs (n=428) in Turkey. Polymerase chain reaction (PCR) and sequencing were used to characterize genes encoding β-lactamase and plasmid mediated quinolone resistance (PMQR). Antimicrobial susceptibility testing and PCRs for virulence genes and phylogenetic groups were also performed. Cefotaxime resistant

. coli isolates were detected in 95 (.2%) of the swab samples. Sequencing analysis results showed occurrence of various β-lactamase genes: bla_CTX-M-15 (62), blaTEM-

1b

(42), bla_CMY-2 (

22

), bla_CTX-M-3 (16), bla_CTX-M-1 (15), bla_OXA-1 (

9

) and bla_SHV-12 (3) alone or in combination. The most frequently encountered phylogenetic group was group A₁ (35.8%), followed by group D₂ (

22

.1%),

B

1 (15.8%), D₁ (

9

.

5

%), A₀ (7.

4

%),

B2₂

(

5

.3%) and

B2₃

(

4

.2%), respectively. PMQR genes, aac(

6

’)-Ib-cr, qnrS1 and qnrB10 were detected in 25.3, 10.

5

and 1.1% of the isolates, respectively. While all isolates were susceptible to imipenem and amikacin, resistance rates to non-β-lactam antibiotics ranged from 20.0% for tobramycin to 56.8% for tetracycline. The virulence genes were only detected in 34 (36.2%) of the isolates and this isolates carried single or various combination of virulence genes of iucD, papC, papE, f17a-A and eaeA. Four isolates were identified as human virulent pandemic CTX-M-15 producing

E

. coli clone O25

b

:ST131/

B

2. To the best of our knowledge, this is the first study to show fecal carriage of ESBL/pAmpC type β-lactamase producing

E

. coli isolates among dogs in Turkey.

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The gamma-ray spectrum and the conversion-electron spectrum are measured in the decay of the Tb¹⁵² activity. The L-subshell electron lines of the 586.7 keV +→2₁⁺ transition are separated by the ion-free beta-ray spectrometer. The M1-2 mixing ratio, δ², and the dimensionless ratio X of 0-2 mixing of the 586.7 keV transition are obtained to be δ²≤0.16 and 0.034≤X≤0.038, respectively. The 2 branching ratio (2; +→0_g⁺): (2; +→2₁⁺): (2; +→0₁⁺) is determined to be 0.023 : 1.0 : ..

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A full account is given of the chemical behavior observed for 7, -dialkyladeninium salts (16). On treatment with boiling 1N aqueous NaOH for 60min, 16a, , d, (X=I), 16c (X=Br), and 16f (X=) rearranged to isomeric , 7-dialkyladenines (21a-f) in 50-% yields. Treatment of the salts with 0.N aqueous Na₂CO₃ at room temperature for 30-90min or with Amberlite CG-400 (OH^-) in H₂O at room temperature gave the ring-opened derivatives a-f (in the trans-formamide form) in 56-83% yields, and rate constants for the ring-opening reactions of 16a, , d-g (X=) and 16c (X=Br) leading to a-g were determined in H₂O at pH .84 and ionic strength 0.50 at 25°C. Cyclization of a with NaH in AcNMe₂ at room temperature or with boiling 1N aqueous NaOH produced 21a in 84% or 72% yield, respectively.In solution, the trans-formamides seemed to transform slowly into the cis-formamides 23, attaining equilibria. The existence of such an equilibrium in D₂O or Me₂SO- at 25°C or in H₂O at pH .84 and ionic strength 0.50 at 25°C was kinetically confirmed in the case of a, and the mechanism of the rearrangement of 16 to 21 through is discussed on the basis of the above kinetic results and Deslongchamps' theory of stereoelectronic control. On treatment with in MeOH at room temperature, 16a (X=I) furnished the 7, 8-dihydro derivative 28 (84% yield), which slowly decomposed in H₂O at 60°C to give a in 49% yield.The 7, -dialkyladeninium salts (16) were found to be obtainable from N'-alkoxy-1-alkyl--formamidoimidazole--carboxamidines () through an alternative synthetic route : Alkylations of with alkyl halides in HCONMe₂ in the absence of base, followed by hydrogenolysis of the N'-alkoxy group and cyclizatio (or vice versa) produced 16 in acceptable yields. In order to interpret the proton nuclear magnetic resonance spectrum of a, the 2-deuterated species 26 was also synthesized from 24 via 25 and 27.

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In the first part of the present work the interaction of glycophorin with dimyristoylphosphatidylcholine (DMPC) is studied by freeze fracture electron microscopy, densitometry, calorimetry, and 90° static light scattering. An exothermic lipid/protein interaction energy of W_P=190 kJ•mol^-1 was found by application of the well known Van Laar relation for the displacement of the freezing point and the Gibbs-Duhem relationship. Secondly, the effects of Ca²⁺ on the lipid/protein interaction were studied. Following Ca²⁺ addition a remarkable decoupling of the interaction of the glycophorin head group with the bilayer surface was revealed by densitometry and gold-labeling electron microscopy. It is estimated that about 80% of lipid once disturbed by the adsorption of glycophorin head groups is decoupled after addition of Ca²⁺. Thirdly, the selective interaction of glycophorin with binary lipid mixtures was studied, including the mixtures of DMPC with dimyristoylphosphatidylserine (DMPS) and dilauroylphosphatidylcholine (DLPC), and the mixture of dipalmitoylphosphatidylcholine (DPPC) with DLPC.

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Hingganite, hellandite and wodginite occur in druse type pegmatite in quarries at Tahara, Hirukawa-mura, Ena-gun, Gifu prefecture, Japan. Two kinds of hingganite, (…)

Σ1.91Fe²

+_0.09Be_2.08Si_2.08O_8.09(OH)

1.91

and (Ce_0.54Y_0.51Nd_0.31…)_Σ2.08Fe²⁺

0.41Be_1.96Si_1.96O_8.87

(OH)_1.13, were found as colorless (hingganite-(Y)) to light brown (hingganite-(Ce)) euhedral crystals associated with quartz, feldspar, mica, cassiterite, stokesite, flourite, chlorite, sphene, and an unknown mineral chemically related to hingganite. Hellandite, (

Ca_5.75Y_3.70Nd_0.24Dy_0.21

…)_Σ10.65 (AI_1.45Mn_0.25Ti_0.21Fe_0.11) (OH)

4

[

Si₈B₈O_40.22

(OH)_3.78] occurs as an aggregate of colorless transparent crystals covering surface of hingganite. The associated minerals of hellandite are quartz, flourite, chlorite and zeolite group minerals. Wodginite, Mn_3.84 (Sn_1.53 Ti_1.11Fe³⁺_0.60W_0.31Ta_0.27Zr_0.18) (Ta_7.99Nb_0.01)O₃₂ occurs as a black prismatic crystal on feldsper, associated with quartz, mica, topaz, beryl, flourite. The chemical compositions and X-ray crystallographic data of these minerals are given and are compared and discussed with data previously reported. Lattice parameters: Hingganite-(Ce), monoclinic, a=

9

.996(10),

b

=7.705 (7), c=

4

.792(

4

) Å, β=90.06(

4

)°; Hellandite, monoclinic, a=18.

91

(2),

b

=

4

.684(

6

), c=10.30(

6

) Å, β=111.7(1)°; Wodginite, monoclinic, a=

9

.513(

9

),

b

=11.456(12), c=

5

.108(

4

) Å, β=

91

.09(

9

)°.

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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), C (3), D (), () X(), Y (7) and Z (8) were confirmed by extensive 1D and 2D NMR spectral data and X-ray analysis. Blazeispirols A (1), (2), C (3), D () and () were des-A-ergostane type compounds having spiroacetal structure as a side chain. Blazeispirols X () and Y (7) were determined to be (20S, S, 23R, 24S)-1 (10→) abeo-14β, :, 25-diepoxyergosta-,7,,11-tetraene-3α,23-diol and (20S, S, 23R, 24S)-14β,:,25-diepoxy-,23-dihydroxyergosta-,7,11-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>C-labeled acetates and methionine to the growing cultures of A. blazei. The labeling patterns of 1 derived from singly and doubly ^<13>C-labeled acetates were consistent with that of ergosterol reported previously except for the A-ring and then ^<14>C-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 C-, C- and C-1, C-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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Eight new sterols, , 8α-epidioxy-(, 24R)-23-methylergosta-, -dien-3β-ol (1), 3β, , -trihydroxy-(, 24R)-23-methylergosta-7, -dien--one (2), 3β, , -trihydroxy-(24S)-ergost-7-en--one (3), 3β, , , 14α-tetrahydroxy-(, 24R)-ergosta-7, -dien--one (), (, 24R)-ergosta-7, -diene-3β, , , -tetrol (), , -epidioxy-3β-hydroxy-(, 24R)-ergosta-7, -dien--one (), , -epidioxy-3β-hydroxy-(24S)-ergost-7-en--one (7) and , -epoxy-(, 24R)-ergosta-8, -diene-3β, 7β, 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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Melithasterols A-D (1-), isolated from a gorgoinan coral Melithaea ocracea of Okinawa, were shown to be cholestane-, 24-methyl--dehydrocholestane-, -dehydrocholestane-, and 24-methylenecholestane-derivatives. respectively, having a common 3β, 7α -dihydroxy-α, α-epoxy-Δ^8 steroid nucleus. This was confirmed by direct comparison with the authentic sample prepared by lead tetra-acetate oxydation of cholest--ene- 3β, α, 8α-triol 3-monoacetate. Twelve new polyhydroxysterols were isolated from an Alcyonium sp. (7,8,), and Sclerophytum sp. (14,16,19,20,21,a,23,26,28) soft corals collected off the coasts of the Andaman and Nicobar Islands in the Indian Ocean. All the Sclerophytum sp. soft corals contained 17a or its 25-deacetyl derivative. Compounds 7 to were identified as 24-methylenecholest--ene- 3β, 16β-diol-3-0-α-L fucoside (7) and its 7β-(8) and 7α-hydroxy () derivatives. Compound 14 was shown to be 24S-24-methylcholest--ene-3β,25ξ,26-triol and was correlated to the known compound 15 by α, β-glycolation. Compound 16 was shown to be β, α-isomer of 17, correlating to 17 by PCC oxidation followed by dehydration. Compound 19 was identified with 25-deacetyl derivative of the known compound lobosterol (19a) by hydrolysis of authentic lobosterol. Compounds 20 and 21 were shown to be 7-dehydro-(20) and -dehydro-(21) derivative of 17a and 17, respectively, by comparisons of their spectral data with reference compounds. Compounds a and 23 were 24S-methylcholestane-3β, α 25-triol--one 25-monoacetate (a) and its 25-deacetoxyl derivative (23). Partial PCC oxidation of 17a afforded a. Compounds 26 (andamansterol) and 28 (nicobarsterol) were shown to be gorgost--ene-3β, α. 11α, 21-tetrol and novel secosteroid, 11,21-cyclo--homo-11-oxa-, 11-secoergostane-3β, α, 12ξ-triol--one, respectively, by spectral analyses (H-HCOSY, HMQC, HMBC).

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Chemical properties of ergosta-, , 8(14), -tetraen-3-one (1) were investigated. Though 1 is rather stable to acids or bases, it reacts easily with two moleculres of oxygen on irradiation with UV light to give , -epidioxy-14α-hydroperoxyergosta-, 7, -trien-3-one (2), which is transformed successively to , 7α;8α, -diepoxy-14α-hydroperoxyergosta-, -dien-3-one (3) and 14α-hydroperoxy--hydroxyergosta-, 7, -triene-3, -dione () under these reaction conditions.

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