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  • Suguru TAKATSUTO, Kiyomi KOBAYASHI, Tsuyoshi WATANABE, Hiroki KURIYAMA, Tokuo FURUSE
    Agricultural and Biological Chemistry
    1988年 52 巻 12 号 3217-3218
    発行日: 1988年
    公開日: 2006/04/05
    ジャーナル フリー
  • Tsuyoshi WATANABE, Hiroki KURIYAMA, Tokuo FURUSE, Kiyomi KOBAYASHI, Suguru TAKATSUTO
    Agricultural and Biological Chemistry
    1988年 52 巻 8 号 2117-2118
    発行日: 1988年
    公開日: 2006/04/05
    ジャーナル フリー
  • 小田切 孝人, 田代 眞人
    ウイルス
    2013年 63 巻 2 号 233-240
    発行日: 2013/12/25
    公開日: 2014/10/31
    ジャーナル フリー
  • Keishi Hata, Fuyuki Sugawara, Naganori Ohisa, Saori Takahashi, Kazuyuki Hori
    Biological and Pharmaceutical Bulletin
    2002年 25 巻 8 号 1040-1044
    発行日: 2002年
    公開日: 2002/08/01
    ジャーナル フリー
    We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MC
    3
    T
    3
    -
    E
    1. Sixteen phosphate buffered saline (PBS),
    8
    boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MC
    3
    T
    3
    -
    E
    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 (
    22E
    ,24R)-ergosta-7,
    22
    -diene-
    ,
    ,
    -triol (1). 1 induced ALP activities of MC
    3
    T
    3
    -
    E
    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 MC
    3
    T
    3
    -
    E
    1 cells by 1, ergosterol (2), ergocalciferol (
    3
    ), cholesta-
    ,
    ,
    -triol (4), 7-dehydrocholesterol (
    5
    ) and cholecalciferol (
    6
    ) were tested. The enzyme activities of MC
    3
    T
    3
    -
    E
    1 cells were increased
    3
    .0-fold by 10 μM 1 and 2.4-fold by 10 μM 4. However, 2,
    3
    ,
    5
    and
    6
    did not induce MC
    3
    T
    3
    -
    E
    1 cell ALP activity at 0.1—10 μM. These results suggested that the OH groups at C-
    5
    and/or C-
    6
    of 1 and 4 played an important role in their differentiation-inducing activities on MC
    3
    T
    3
    -
    E
    1 cells. Furthermore, 1 suppressed induction of MC
    3
    T
    3
    -
    E
    1 cell apoptosis by serum starvation.
  • R.G. WAN, P.J. GUO
    地盤工学会論文報告集
    1999年 39 巻 6 号 1-11
    発行日: 1999/12/15
    公開日: 2008/02/29
    ジャーナル フリー
    This paper outlines a mathematical description of the stress dilatancy behaviour of granular materials which accounts for stress level and void ratio dependencies. The consideration of these aspects has important implications in the modelling of granular material behaviour. In fact, granular material mechanical response is largely dominated by the evolution of dilatancy, fabric and void ratio histories. The starting point in this study is the well established Rowe's theory which is revisited and ultimately modified by introducing a factor linked to governing state parameters in order to describe the complete behaviour of granular materials during deformation. Numerical simulations of triaxial tests on granular materials at different void ratios and stress levels are herein presented to illustrate the model.
  • Suguru TAKATSUTO
    Agricultural and Biological Chemistry
    1988年 52 巻 9 号 2361-2363
    発行日: 1988年
    公開日: 2006/04/05
    ジャーナル フリー
  • 澁谷 啓, 田中 洋行
    地盤工学会論文報告集
    1996年 36 巻 4 号 45-55
    発行日: 1996/12/15
    公開日: 2008/02/29
    ジャーナル フリー
    An empirical equation in use for estimating the pseudo-elastic shear modulus, Gf, of subsoil, associated with shear strains less than 0.001% is proposed in this paper. In a series of in-situ seismic cone tests performed nationwide, the profiles of both Gf and the in-situ void ratio,
    e0
    , with depth were successfully characterised at five sites, each comprising a soft clay layer deposited in the Holocene era. The database which comprised the original data from the field and laboratory tests, coupled with similar information on well-documented Holocene clay deposits in Europe, was statistically analyzed in attempts to determine a generalised relationship with which Gf of soft clay may be reasonably estimated only from routinely available borehole data; that is
    e0
    and the current geostatic effective overburden pressure, σ'v. An empirical relationship, Gf=
    5
    , 000
    e0
    -
    1.5
    √(σ'v) (kPa), was derived from the statistical analysis applied to data from seven different clays worldwide, for which
    e0
    extended over a range between 1 and
    5
    , and the overconsolidation ratio ranged roughly between 1 and 2. The applicability of the proposed relationship was evaluated for two case records, each in which the clay exhibited unusual behavior; i.
    e
    ., the undrained shear strength remained more or less constant with depth due to the existence of artesian pressure at one site, and, at the other, Gf decreased, whereas
    e0
    increased, with depth. It was demonstrated that even in these clay deposits exhibiting exceptional profiles, the proposed relationship was capable of predicting Gf with a reasonable accuracy by determining the profiles of
    e0
    and σ'v with depth. In addition, the prediction when compared to Gmax from carefully performed laboratory cyclic tests, yielded a better estimate of Gf from the in-situ seismic survey. Despite the fact that the empirical relationship was initially designated to estimate Gf of soft clays, it may be equally applicable to sandy deposits. This was verified by comparing it to similar, and well-established, relationships developed for sands. A case record as such is also described for a loose sand deposit at Higashi-Ohgishima in Tokyo Bay which was placed in 1960's by land reclamation.
  • Grover Loening
    日本航空学会誌
    1963年 11 巻 119 号 373-380
    発行日: 1963年
    公開日: 2009/05/25
    ジャーナル フリー
  • 榎 明潔, 八木 則男, 矢田部 龍一, 一本 英三郎
    土質工学会論文報告集
    1991年 31 巻 2 号 1-13
    発行日: 1991/06/15
    公開日: 2008/02/29
    ジャーナル フリー
    It has been shown after mathematical and mechanical investigation that Limit Equilibrium Method (LEM) can be considered as a method to obtain the necessary condition of Slip Line Method (SLM), and that the solution can be obtained under the condition that Fs=1 and ∂Fs/∂θ=O, where Fs is the safety factor and θ is the inclination of the plane on which the safety factor is defined. Next, the generalized LEM (GLEM) is proposed, dealing with the following points : (1) Triangular or quadrangular blocks can be treated; (2) Safety factors are defined also on interblock planes; and (
    3
    ) All types of plastic problems, slope stability, bearing capacity, and earth pressure are identically formulated. Two situations regarding treatment of the moment equilibrium condition are discussed. GLEM is applied to well-known problems. The results agree well with those obtained by theoretical methods. GLEM can be used to obtain the distribution of earth pressure or bearing capacity. GLEM, Iike ordinary LEM, is very effective for the practical problems, but GLEM is more theoretical and it can result in more accurate solutions.
  • 澁谷 啓, 三田地 利之
    土質工学会論文報告集
    1994年 34 巻 4 号 67-77
    発行日: 1994/12/15
    公開日: 2008/02/29
    ジャーナル フリー
    In this paper, consideration is given as to how to characterize depth-variation for the small-strain shear modulus of natural clay sedimentation, in a state of normal consolidation. A case study was carried out for a relatively uniform clay layer deposited in the Holocene era. Initially, the effects of both strain and in-situ stress levels on secant shear modulus were carefully examined in cyclic torsion shear tests using undisturbed samples, which were recovered at different depths in a test borehole. The range of shear strain examined was between 0.001% and 1%. Similar examination was made for a silty clay using reconstituted samples that were isotropically consolidated at different stress levels. On the basis of the results of these laboratory tests, together with the shear modulus from an in-situ seismic survey, the small-strain shear modulus was formulated in terms of the stress and strain levels, and linked also to undrained shear strength. Interactions of the small strain stiffness between in-situ and laboratory are discussed in depth with an attention paid to the existing aging effect in the original subsurface condition.
  • N. YOSHIDA, N.R. MORGENSTERN,
    D
    .H. CHAN
    土質工学会論文報告集
    1991年 31 巻 1 号 121-130
    発行日: 1991/03/15
    公開日: 2008/02/29
    ジャーナル フリー
    Some existing analytical methods which have been used in geotechnical engineering are modified to handle the shear strength reduction with time due to softening in fissured, over-consolidated clays and mudstones. These are limit equilibrium analysis of slope stability, calculation of earth pressure and calculation of stress and displacement around a tunnel. The softening effect is incorporated in these analyses using the failure criterion and the time-dependent strength parameters proposed previously by the authors. Examples are presented which emphasize the importance of appreciating the softening effect in analyses and further illustrate that the effect of shear strength reduction with time due to softening could easily be captured with existing analytical methods.
  • 藤崎 正治
    日本航海学会誌
    1965年 33 巻 79-83
    発行日: 1965/07/25
    公開日: 2017/09/26
    ジャーナル フリー
    Three objects are A,
    B
    and C. The ship's positon is P. This is the instrument by which the ship's course will be recorded on the chart, if one on board is moving index mirror so that image A may be on
    B
    through telescope on sextant and the other is moving another sextant so that image C may be on A. Figure 1 shows the principle of this instrument except sextant, where
    D
    is the point which AB^2=AC・
    AD
    . Take Q and
    E
    such that AB^2=AP・AQ, AB=
    AE
    . then follows ∠ABQ=∠APB, ∠ADQ=∠APC. Fig.2 shows the outline of this instrument put on paper except sextant. Fig.
    3
    , 4,
    5
    ,
    6
    are in detail of fig.2. Fig.7 shows the sextant with synchromotor, (12) shows the cover of syncromotor. Fig.
    8
    ,
    9
    shows the part of instrument which must be reformed next time.
  • 汪 発武, 佐々 恭二, 福岡 浩
    地盤工学会論文報告集
    2000年 40 巻 1 号 35-46
    発行日: 2000/02/15
    公開日: 2008/02/29
    ジャーナル フリー
    By employing an undrained cyclic loading ring-shear apparatus, a series of tests to reproduce the dynamic behavior of the Nikawa landslide induced by the January 17, 1995 Hyogoken-Nambu earthquake, is conducted. The test sample is Osaka-group coarse sandy soil taken from the landslide. The initial stress condition acting on a soil element in the sliding surface is applied to the sample. Based on the seismic records monitored at the JR Takarazuka Station, the input seismic wave is synthesized to reproduce the seismic stress acting on the sliding surface. The test results show that the soil failed due to the dynamic loading of the earthquake. The most important results are the excess pore water pressure generation and the acceleration of shear displacement continuing after the main shock. Combined with the grain crushing at the shear zone and the volume reduction in the drained constant-speed ring-shear test, the mechanism of this landslide is interpreted as, shear displacement causing grain crushing in the shear zone and volume reduction, and then resulting in a localized liquefaction phenomenon, "sliding-surface liquefaction". This geotechnical simulation test provides a reasonable interpretation of this highly mobile landslide.
  • Özkan ASLANTAŞ, Ebru Şebnem YILMAZ
    Journal of Veterinary Medical Science
    2017年 79 巻 6 号 1024-1030
    発行日: 2017年
    公開日: 2017/06/16
    [早期公開] 公開日: 2017/04/27
    ジャーナル フリー

    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

    E
    . coli isolates were detected in 95 (
    22
    .2%) of the swab samples. Sequencing analysis results showed occurrence of various β-lactamase genes: blaCTX-M-15 (62), blaTEM-
    1b
    (42), blaCMY-2 (
    22
    ), blaCTX-M-
    3
    (16), blaCTX-M-1 (15), blaOXA-1 (
    9
    ) and blaSHV-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, qnr
    S1 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.

  • Nicholas ISYUMOV, Eric HO, Peter KING, David SURRY, Barry VICKERY
    日本風工学会誌
    2010年 35 巻 4 号 265-271
    発行日: 2010/10/31
    公開日: 2011/04/01
    ジャーナル フリー
  • 佐藤 敬之輔
    デザイン学研究
    1970年 1970 巻 11 号 45-55
    発行日: 1970/03/30
    公開日: 2017/07/25
    ジャーナル フリー
    [1] The purpose of this reserch is to make clear what type of design can give good effects to win the high readership score. At the begining I had to know what factors decide the readership score, and how to change the quality of the desing into numerical value. I have used the method of multi-dimentional analysis with the help of a computer, and got the estimation formula, with 7 kinds of factors, as follows ; A^^〜=
    B
    +C+
    D
    +K+
    aE
    +bF+cG. A^^〜=estimated values of the readership score. 1)
    B
    , C,
    D
    , K : these four factors are given as category values (so we call them); each factor is classified into several categories.
    B
    =week day, classified into 7 categories. C=pages of a newspaper, which are characterized by the kinds of articles, news, and the other reading matters, classified into
    22
    categories.
    D
    =kinds of goods and trades of the advertizement, classified into 14 catedories. K=constants, given to each 13 surveys. 2)
    E
    , F, G : these factors are given as numerical values. G=area of advertizement, measured by the unit of column in the whole page length, being classified into
    6
    kinds of area (2.
    5
    ,
    3
    .
    5
    ,
    5
    , 7, 10, 15) and 15 column means a whole page, about 2,000cm^2.
    E
    , F are the marks obtained in the design of advertizements.
    E
    =sum of the marks obtained in each design element on the advertizement. F=the marks obtained on the whole effect of the design.
    3
    ) a,
    b
    , c : coefficients Using the above formula with the category values and the coefficients, we can obtain the naked design effect from the actual value A of readership score:
    aE
    +bF=A-(
    B
    +C+
    D
    +K+cG). In this research, I used 1,829 data of readership score from 1960 to 1968, being obtained by 13 survevs, spring and autumn twice a year. The sample of size each survey was
    3
    ,541, 2,251, or 200 in the other 11 surveys. Multiple correlation coefficient between the estimated value A^^〜 and the actual value A is 0.951. The table 2^* shows the contribution indexes of each factor by
    3
    kinds of expression-(1) Range : the absolute difference between the maximum and the minimum category values, (2) Standard deviations of the category values, (
    3
    ) Partial correlation coefficient : the relationship between the actual values A and each factors. *see the table 2 in the thesis in Japanese. [2] The important point was in the determination of the values of
    E
    , F.
    E
    is the sum of the marks obtained in each design element, classified into four kinds :
    E
    =
    E
    _1+
    E
    _2+
    E
    _
    3
    +
    E
    _4. design elements [table]
    E
    _1,
    E
    _2,
    E
    _
    3
    ,
    E
    _4, these values have the
    5
    grades, as 0, 1, 2,
    3
    , 4 and 0 is given to the design that has no attractive effect or no applicable element. And
    E
    obtain the marks of 0 to
    9
    grades as the sum of them. The values of F have also
    5
    grades, 0 to 4. The principles to determine the values of
    E
    , F are as follows : a) The marks obtained of
    E
    , F must be the relative values among the each survey, and at the same time, they must have constancy within the same survey-the same elements of design must win the same marks obtained.
    b
    ) They must be determined as to win the highest multiple correlation coefficient, when they are put into the estimation formula. c) They must be reasonable. In order to justify them, we must carry many researches on the actual condition. The frequency of accurence of each grade of
    E
    , F values, as the table
    5
    -4, and
    5
    -
    5
    in the thesis in Japanese.
  • 樋口 貴也, 石原 研而, 塚本 良道, 桝尾 孝之
    地盤工学会論文報告集
    1998年 38 巻 1 号 221-227
    発行日: 1998/03/15
    公開日: 2008/02/29
    ジャーナル フリー
    This paper reports deformation and strength characteristics for a geogrid-reinforced granular soil on a large-scale plane strain compression apparatus. The influence of intensity and types of geogrid reinforcement is specifically discussed. It was found that as more reinforcement layers are used, the strength of the reinforced soil increased. In cases where reinforcement is most intensely used, the reinforcement layers in the samples were eventually subject to breakage due to plane strain compression and the reinforced soil failed. In cases where reinforcement is less intensely used, the reinforced soil reached failure without any sign of reinforcement breakage. It was also found that types of reinforcement have a significant influence on the lateral deformation of the reinforced soil, where stiffer reinforcement provides more constraints on lateral deformation of the reinforced soil. It can be superceded, however, by the influence of reinforcement intensity. The small stain measurement by means of LDT observed that the stiffness of non-reinforced soil begins to decrease more rapidly at a strain level of 0.05∼0.15%, compared to the reinforced soil. The experimental results also indicate that the relationship between the apparent angle of internal friction and the geometry of the structure of the reinforced granular soil seems to exist for the geogrid reinforcement used in the tests reported in this paper.
  • Masuko Kobori, Mitsuru Yoshida, Mayumi Ohnishi-Kameyama, Toshiyuki Takei, Hiroshi Shinmoto
    Biological and Pharmaceutical Bulletin
    2006年 29 巻 4 号 755-759
    発行日: 2006年
    公開日: 2006/04/01
    ジャーナル フリー
    We purified a sterol with antitumor activity from the edible mushroom Sarcodon aspratus (BERK.) S. ITO and identified it as
    ,
    -epidioxy-
    22E
    -ergosta-
    6
    ,
    9
    (11),
    22
    -trien-
    -ol (
    9
    ,11-dehydroergosterol peroxide (
    9
    (11)-DHEP)). Purified
    9
    (11)-DHEP was a more effective inhibitor of HL60 leukemia cell growth and stronger apoptosis-inducer than
    ,
    -epidioxy-
    22E
    -ergosta-
    6
    ,
    22
    -dien-
    -ol (ergosterol peroxide (EP)) that we had previously identified as an apoptosis inducer. Moreover,
    9
    (11)-DHEP selectively suppressed the growth of HT29 human colon adenocarcinoma cells but not WI38 normal human fibroblasts. After
    5
    d
    incubation of HT29 with 7 μM
    9
    (11)-DHEP, the number of S phase cells decreased from 23 to 15% of total diploid cells and 17% became hypodiploid. Expression of the cyclin-dependent kinase inhibitor 1A (p21, WAF1, Cip1) (CDKN1A), which has been shown to cause cell cycle arrest and apoptosis in HT29 cells, was induced by
    9
    (11)-DHEP. These results suggest that
    9
    (11)-DHEP inhibits HT29 cell growth by inducing CDKN1A expression, thus causing cell cycle arrest and apoptosis.
  • 伊東 常男, 富井 保雄, 内藤 貴之, 山村 美奈子, 石川 一郎, 川原 徳夫, 水野 義久, 小倉 治夫
    Chemical and Pharmaceutical Bulletin
    1989年 37 巻 8 号 2197-2199
    発行日: 1989/08/25
    公開日: 2008/03/31
    ジャーナル フリー
    5
    -Amino-
    6
    -mercapto-1,
    3
    -dimethyluracil (2) was prepared by the treatment of
    5
    ,
    6
    -diamino-1,
    3
    -dimethyluracil (1) with liquid H2S and pyridine in a sealed steel tube at 60°C for 20 h. Thiazolo[
    5
    , 4-
    d
    ]pyrimidinediones
    3
    a,
    b
    were obtained from 2 by cyclization with HCO2H and AcOH.Under stringent conditions, however, 1 was converted into the
    5
    ,
    9
    -dihydrodipyrimido[4,
    5
    -
    b
    :
    5
    ', 4'-
    e
    ][1, 4]thiazine derivtive 4a.The structure of 4a was confirmed by spectral (nuclear magnetic resonance and mass spectra) data and by comparison with a sample which was prepared from 2 and
    5
    -hydroxy-1,
    3
    -dimethyluracil.Benzylation of 4a gave 1,
    3
    , 7,
    9
    -tetramethyl-
    5
    -benzyl (or p-bromobenzyl)-
    5
    ,
    9
    -dihydrodipyrimido[4,
    5
    -
    b
    :
    5
    ', 4'-
    e
    ][1, 4]thiazine-2, 4,
    6
    ,
    8
    -(1H,
    3
    H, 7H)-tetrone (4
    b
    , c) and 1,
    3
    , 7,
    9
    -tetramethyl-
    5
    -benzyl (or p-bromobenzyl)-
    5
    ,
    9
    -dihydropyrrolo[
    3
    , 2-
    d
    : 4,
    5
    -
    d
    ']dipyrimidine-2, 4,
    6
    ,
    8
    -(1H,
    3
    H, 7H)-tetrone (
    6
    a,
    b
    ).
  • 廣谷 正男, 金子 麻美, 廣谷 聖子, 浅田 善久, 吉川 孝文
    天然有機化合物討論会講演要旨集
    2000年 42 巻 48/P-13
    発行日: 2000/10/01
    公開日: 2017/08/18
    会議録・要旨集 フリー
    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),
    B
    (2), C (
    3
    ),
    D
    (4),
    E
    (
    5
    ) X(
    6
    ), Y (7) and Z (
    8
    ) were confirmed by extensive 1
    D
    and 2
    D
    NMR spectral data and X-ray analysis. Blazeispirols A (1),
    B
    (2), C (
    3
    ),
    D
    (4) and
    E
    (
    5
    ) were des-A-ergostane type compounds having spiroacetal structure as a side chain. Blazeispirols X (
    6
    ) and Y (7) were determined to be (20S,
    22
    S, 23R, 24S)-1 (10→
    6
    ) abeo-14β,
    22
    :
    22
    , 25-diepoxyergosta-
    5
    ,7,
    9
    ,11-tetraene-
    3
    α,23-diol and (20S,
    22
    S, 23R, 24S)-14β,
    22
    :
    22
    ,25-diepoxy-
    9
    ,23-dihydroxyergosta-4,7,11-triene-
    3
    ,
    6
    -dione by comparison of extensive 1
    D
    and 2
    D
    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-4, C-
    5
    and C-1, C-10 bonds on retro aldol condensation and Michael reaction via such as intermediate A as shown in Fig. 4. 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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