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  • Joey
    B
    . Tanney, Leonard J. Hutchison
    Mycoscience
    2012年 53 巻 1 号 31-35
    発行日: 2012年
    公開日: 2023/03/31
    ジャーナル オープンアクセス

    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.

  • 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
  • George W. Lee
    燃料協会誌
    1973年 52 巻 3 号 171-177
    発行日: 1973/03/20
    公開日: 2010/06/28
    ジャーナル フリー
  • 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
  • T BAKER, C. RANGACHARYULU
    日本物理学会講演概要集
    1999年 54.2.1 巻 23pSM-6
    発行日: 1999/09/13
    公開日: 2018/03/04
    会議録・要旨集 フリー
  • 末次 康将
    マリンエンジニアリング
    2021年 56 巻 5 号 680-687
    発行日: 2021/09/01
    公開日: 2021/10/12
    ジャーナル フリー
  • I.
    F
    . Davies
    Journal of Light & Visual Environment
    1984年 8 巻 1 号 1_9-1_20
    発行日: 1984年
    公開日: 2011/05/20
    ジャーナル フリー
  • 鍛治 健司, 葛谷 昌之 /, RAYMONDN. CASTLE
    Chemical and Pharmaceutical Bulletin
    1970年 18 巻 1 号 147-156
    発行日: 1970/01/25
    公開日: 2008/03/31
    ジャーナル フリー
    2-Benzyl-
    4
    -chloro-
    5
    -mercapto-3 (2H)-pyridazinone (
    1
    ) was heated in ethanol under reflux for 10 hours to form concurrently 2,
    7
    -dibenzyldipyridazo [
    4
    ,
    5
    -
    b
    :
    4
    ',
    5
    '-
    e
    ]-
    1
    ,
    4
    -dithiin-
    1
    ,
    6
    (2H,
    7
    H)-dione (Ia) (57% in yield) and 2,
    8
    -dibenzyldipyridazo [
    4
    ,
    5
    -
    b
    :
    4
    ',
    5
    '-
    e
    ]-
    1
    ,
    4
    -dithiin-
    1
    ,
    9
    (2H,
    8
    H)-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 [
    4
    ,
    5
    -
    b
    :
    4
    ',
    5
    '-
    e
    ]-
    1
    ,
    4
    -dithiin-
    1
    ,
    6
    (2H,
    7
    H)-dione and the -
    1
    ,
    9
    (2H,
    8
    H)-dione were observed in, not only heating
    4
    -chloro-
    5
    -mercapto-3 (2H)-pyridazinones (
    1
    -3) in polar solvent, but warming
    4
    -mercapto-
    5
    -chloro-3 (2H)-pyridazinones (
    4
    -
    6
    ) 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-
    5
    -benzylpyridazo [
    4
    ,
    5
    -d]-
    1
    , 3-dithiol-
    4
    (
    5
    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.
  • 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.
  • /, 龍岡 文夫, FUMIO TATSUOKA
    地盤工学会論文報告集
    1997年 37 巻 4 号 121-126
    発行日: 1997/12/15
    公開日: 2008/02/29
    ジャーナル フリー
    The design implication of stress-confinement effect of nonwoven geotextile is addressed. The unconfined and confined strengths of a selected needle-punched nonwoven geotextile are used to conduct a comparative design of a granular soil retaining wall based on a limit equilibrium approach. A higher wall may be allowed when considering the confined strength as compared to the unconfined strength. For a selected wall height, confined strength allows for fewer geotextile layers when compared to that designed using unconfined strength. It is recommended that stress-confinement test procedure should be standardized so that confinement effect of some nonwoven geotextiles may be incorporated into an individual wall design procedure.
  • 吉井 一郎
    日本臨床整形外科学会雑誌
    2017年 43 巻 1 号 1-9
    発行日: 2017年
    公開日: 2018/04/05
    ジャーナル 認証あり

    背景と目的:ステロイド性骨粗鬆症は,積極的な治療介入が必要とされる.その第一選択薬はビスホスホネート製剤(以下ビス)であるが,近年,デノスマブ(以下デノス)も注目を浴びている.ステロイド性骨粗鬆症の骨密度に対する両者の効果を比較検討した.

    方法:ステロイド性骨粗鬆症の管理と治療ガイドライン:2014年改訂版の薬物療法開始の基準を満たした患者を対象とした.無治療群(N群)と,治療介入群として当初よりビスで治療したBB群,ビス後デノスに変更したBD群,デノスで治療したDD群,デノス後ビスに変更したDB群を抽出し,ステロイド投与を開始した時,ステロイド性骨粗鬆症に対する治療を開始した時または薬剤変更から

    6
    カ月後の腰椎,大腿骨頚部と大転子部の骨密度を測定し,それらの変化を統計学的に比較検討した.

    結果:149例が抽出され,その内訳は,N群48例,BB群24例,BD群

    22
    例,DD群21例,DB群34例であった.治療開始時または薬剤変更から
    6
    カ月後にBD群を除くすべての治療介入群で腰椎の骨密度が上昇した.大腿骨の骨密度は,BD群において薬剤変更後に上昇に転じた.

    考察:デノスにはビスと同様の骨密度上昇効果があると考えられた.

    結論:デノスは,ステロイド性骨粗鬆症治療の第一選択薬となり得る.

  • 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,
    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.

  • 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.
  • Zhe Fang, Su Yang Jeong, Hyun Ah Jung, Jae Sue Choi, Byung Sun Min, Mi Hee Woo
    Chemical and Pharmaceutical Bulletin
    2010年 58 巻 9 号 1236-1239
    発行日: 2010/09/01
    公開日: 2010/09/01
    ジャーナル フリー
    Activity-directed isolation of the ethyl acetate, methylene chloride and n-hexane fractions of Gloiopeltis furcata resulted in the isolation of 18 compounds. Their structures were elucidated as 2-(3-hydroxy-
    5
    -oxotetrahydrofuran-3-yl)acetic acid (
    1
    ), glutaric acid (2), succinic acid (3), nicotinic acid (
    4
    ), (
    E
    )-
    4
    -hydroxyhex-2-enoic acid (
    5
    ), cholesterol (
    6
    ),
    7
    -hydroxycholesterol (
    7
    ), uridine (
    8
    ), glycerol (
    9
    ),
    5
    -(hydroxymethyl)-2-methoxybenzene-
    1
    ,3-diol (10), (
    5E
    ,
    7E
    )-
    9
    -oxodeca-
    5
    ,
    7
    -dienoic acid (11), (Z)-3-ethylidene-
    4
    -methylpyrrolidine-2,
    5
    -dione (12), dehydrovomifoliol (13), loliolide (14), cholesteryl stearate (15), palmitic acid (16), cis-
    5
    ,
    8
    ,11,14,17-eicosapentaenoic acid (17) and α-linolenic acid (18) on the basis of spectroscopic and chemical evidences. Their anticholinesterase and antioxidant activities were evaluated via inhibitory activities on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) as well as scavenging activities on
    1
    ,
    1
    -diphenyl-2-picrylhydrazyl (DPPH) radical and peroxynitrite (ONOO). All isolated compounds (
    1
    18) exhibited moderate AChE inhibitory activities with IC50 values ranging from
    1
    .14—12.50 μg/ml, whereas
    1
    ,
    7
    ,
    9
    , 17, and 18 showed mild BChE inhibitory activities with IC50 values ranging from
    5
    .57—15.89 μg/ml. Although most of the compounds isolated were lacking the scavenging activity on DPPH radical and ONOO,
    5
    and 10 showed good DPPH radical scavenging activity, and
    5
    , 10, and 16 showed potent ONOO scavenging activity.
  • 山本 雅史, Abkenar Asad Asadi, 松本 亮司, 根角 博久, 吉田 俊雄, 國賀 武, 久保 達也, 冨永 茂人
    園芸学会雑誌
    2007年 76 巻 1 号 36-40
    発行日: 2007年
    公開日: 2007/03/06
    ジャーナル フリー
    カンキツ主要12種を用いて染色体のクロモマイシン A3(CMA) 染色を行った.染色体は CMA(+) バンドの有無および位置から
    7
    種類に区分できた.すなわち,CMA(+) を A: 両端および動原体近傍に有する,
    B
    : 一方の端部と動原体近傍に有する,C: 両端に有する,D: 一方の端部に有する,
    E
    : CMA(+) がない,
    F
    : 動原体近傍に有する,Dst: 付随染色体を有する D 型,である.各種はこれらのうち 2~
    6
    種類の染色体を有し,独自の CMA バンドパターンを示した.C. medica では 2
    B
    +
    8
    D +
    8
    E
    C. limon では
    1
    B
    +
    1
    C +
    8
    D +
    8
    E
    C. aurantifolia では 2
    B
    +
    9
    D +
    7
    E
    C. aurantium では
    1
    A +
    1
    B
    +
    1
    C +
    7
    D +
    8
    E
    C. sinensis では 2
    B
    + 2C +
    7
    D +
    7
    E
    C. maxima では 3A + 3C +
    4
    D +
    8
    E
    C. paradisi では 2A + 3C +
    6
    D +
    7
    E
    C. ichangensis では 2
    B
    + 2C + 12D + 2
    E
    C. latipes では 2A +
    5
    C +
    8
    D + 3
    E
    C. micrantha では
    1
    B
    + 11D +
    4
    E
    + 2Dst,C. macroptera では 2
    B
    +
    1
    C + 11D + 3
    E
    +
    1
    F
    C. hystrix では 3
    B
    +
    1
    C +
    8
    D + 3
    E
    + 2
    F
    +
    1
    Dst であった.
  • A.M. BRITTO, C. SAVVIDOU, M.J. GUNN, J.R. BOOKER
    土質工学会論文報告集
    1992年 32 巻 1 号 13-25
    発行日: 1992/03/15
    公開日: 2008/02/29
    ジャーナル フリー
    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.
  • 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
  • Yasutomo ISHII, Andrei SMOLYAKOV
    Plasma and Fusion Research
    2008年 3 巻 048
    発行日: 2008/08/20
    公開日: 2009/02/20
    ジャーナル フリー
    Alfven resonance effects on the evolution of a magnetic island driven by an externally applied perturbation are investigated for rotating plasmas. The simulation results show the importance of Alfven resonance for obtaining a perturbed current profile and estimating a critical value of the external perturbation, beyond which the magnetic island grows rapidly. The nonlinear evolution of the externally driven magnetic island is also investigated at low and high viscosities ν. It is shown that the transition phase accompanying the secondary reconnection at the initial X-point in the driven magnetic island evolution occurs in low resistivity and viscosity plasmas.
  • 香山 滉一郎, 森下 政夫, 張 国鋒
    粉体および粉末冶金
    2006年 53 巻 5 号 419-429
    発行日: 2006年
    公開日: 2006/12/19
    ジャーナル オープンアクセス
    The phase diagrams of the Ni-Mo-
    B
    and Ni-W-
    B
    ternary systems in the region of less than 50mol%
    B
    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:
    E1
    :L (1365K, 71.
    5
    mol%Ni-
    6
    .
    0
    mol%Mo-
    22
    .
    5
    mol%
    B
    )=(Ni)+
    Ni3B
    +
    NiMo2B2

    E2
    :L (1355K, 62.
    5
    mol%Ni-2.
    5
    mol%Mo-30.
    5
    mol%
    B
    )=
    Ni3B
    +
    Ni2B
    +
    NiMo2B2

    E3
    :L (1445K, 42.
    0
    mol%Ni-30.
    6
    mol%Mo-10.3mol%
    B
    )=(Ni)+NiMo+
    NiMo2B2

    P1
    :L (1812K, 34.
    9
    mol%Ni-42.3mol%Mo-
    22
    .
    8
    mol%
    B
    )+MoB=
    Mo2B
    +
    NiMo2B2

    P2:L (1633K, 42.3mol%Ni-40.
    4
    mol%Mo-17.3mol%
    B
    )+Mo=
    Mo2B
    +
    NiMo2B2

    P3:L (1812K, 53.
    5
    mol%Ni-33.
    7
    mol%Mo-12.
    8
    mol%
    B
    )+Mo=NiMo+
    NiMo2B2

    E1
    :L (1622K, 51.
    0
    mol%Ni-31.
    6
    mol%W-17.
    4
    mol%
    B
    )=(Ni)+W+
    NiW2B2

    E2
    :L (1260K, 71.
    0
    mol%Ni-
    7
    .
    0
    mol%W-
    22
    .
    0
    mol%
    B
    )=(Ni)+
    Ni3B
    +
    NiW2B2

    E3
    :L (1291K, 65.
    4
    mol%Ni-
    4
    .
    8
    mol%W-29.
    8
    mol%
    B
    )=
    Ni2B
    +
    Ni3B
    +
    NiW2B2

    P1
    :L (2115K, 23.
    8
    mol%Ni-43.
    1
    mol%W-33.
    1
    mol%
    B
    )+WB=
    W2B
    +
    NiW2B2

    P2:L (1657K, 48.
    9
    mol%Ni-33.
    1
    mol%W-18.
    0
    mol%
    B
    )+
    W2B
    =W+
    NiW2B2

    The calculated phase diagrams are expected to be useful for the development of new Ni-based heat-, corrosion- or wear-resistance alloys.
  • 小林 優, 家坂 貴子, 中野 江身子, 平山 耕一郎
    天然有機化合物討論会講演要旨集
    1989年 31 巻 71/P2-1
    発行日: 1989/09/17
    公開日: 2017/08/18
    会議録・要旨集 フリー
    Six new cembranoids sarcophytol P (3), R (
    4
    ), S (
    5
    ), K (
    8
    ),
    F
    (11), and T (13) were isolated from the soft coral Sarcophyton glaucum. Sarcophytol P (3) was shown to be the 20-hydroxy derivative of the major component sarcophytol A (
    1
    ), and afforded the cyclization product
    6
    in CHCl_3 at room temperature, in a same way as in
    1
    . Sarcophytols R (
    4
    ) and S (
    5
    ) were correlated to
    1
    , by conversion of its
    7
    R,
    8
    R and
    7
    S,
    8
    S epoxide derivatives. Sarcophytol K(
    8
    ) was a 13, 14-dihydroxycembranoid having a
    1
    E
    ,3Z-diene moiety. The absolute configuration of
    8
    and its
    1
    Z,3
    E
    - and
    1
    Z,3Z-isomers sarcophytol
    B
    (2) and J (10) were determined by circular dichroism study of their bis-p-dimethylaminobenzoate derivatives. Sarcophytols
    F
    (11) and T (13) were
    1
    E
    - and
    1
    E
    ,3Z-isomers of
    1
    . Compound 11 showed characteristic broadening of the ^
    1
    H-NMR chemical shifts, due to the restricted conformational interconversion. Using the three cembranoids sarcophytols
    F
    (11,
    1
    E
    ,3
    E
    ), N (15,
    1
    Z,3Z) and T (13,
    1
    E
    ,3Z), spontaneous autoxidation-cyclization, in CHCl_3,was examined, in order to compare the stereochemical course of the reaction with that of
    1
    (
    1
    Z,3
    E
    ), which affords trans-fused bicyclo[
    9
    .3.
    0
    ]tetradecene systems. The
    1
    E
    ,3Z-isomer 13 gave the same cyclization product 18, as in the reaction of
    1
    , even though it is isomeric at C-
    1
    ,3. The
    1
    Z,3Z isomer 15 gave 19, in consequence of the reversed geometry at C-3 of 15. The
    1
    E
    ,3
    E
    -isomer (11) gave the bicyclic product
    22
    , having an antipodal fusion as compared with 19. This was confirmed by PCC oxidation of 19 and
    22
    , giving enantiomeric ketones 23 and 24 respectively. The
    1
    (14)-epoxide 26 was shown to be the immediate precursor of
    22
    , and acounted for the inversion of the geometry at C-
    1
    of the cyclization product. Compound 26 is isomeric with the epoxide 17 derived from
    1
    . The epoxide 17 is the postulated precursor in the conversion of 13 to 18. It is noteworthy that the mode of antipodal fusion of the cyclopentane rings, in 18 and
    22
    , was controlled by the chirality of the epoxy rings. The C-14 hydroxyl group participates in the transannular cyclization, but was found not to be the requisite functional group for the reaction. Similar treatment of cembrene C (30), the parent hydrocarbon of
    1
    , also reacted in CHCl_3 giving the bicyclic product 32.
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