• Title/Summary/Keyword: Analogs

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Silyl-Tranfer Photoreactions of Trimethylsilylmethyl Substituted Acyclic N-Sulfonylbenzamides

  • Oh, Sun-Wha
    • Journal of Photoscience
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    • v.12 no.2
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    • pp.63-66
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    • 2005
  • The azomethine ylide forming photoreaction has been explored by probing the excited state chemistry of several N-trimethylsilylmethyl substituted cyclic and acyclic imides and amide analogs. N-[(Trimethylsilyl)methyl]-N-mesylbenzamide (5) undergoes the excited state C to O silyl migration reaction to produce azomethine ylide intermediate 13. This ylide undergoes electrocyclization to form transient aziridine intermediate 14 which react further by ring opening to generate N-phenacylamine product 10. On the other hand, photolysis of N-[N-mesyl-N-(trimethylsilyl)methyl]aminoethyl-N-mesylbenzamide (8) brings about desilylation resulting in the production of dimer 17.

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High Pressure X-Ray Diffraction Study on a Goethite using Synchrotron Radiation (방사광을 이용한 괴타이트에 대한 고압 X-선 회절연구)

  • 김영호;이지은
    • Journal of the Mineralogical Society of Korea
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    • v.10 no.2
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    • pp.75-81
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    • 1997
  • High pressure X-ray diffraction study was carried out on a natural FeO(OH)-goethite to investigate its compressibility at room temperature. Energy dispersive X-ray diffraction method was employed using Mao-Bell type diamond anvil cell with Synchrotron Radiation. MgO powder was compressed together with goethite for the high pressure determinations. Bulk modullus was determined to be 147.9 GPa by the Birch-Murnaghan equation of state under assumption of K0' of 4. This value was subjected to compare with its structural analogs and related materials.

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Studies on Asymmetric Synthesis of Carbaprostacyclin and Its Structural Analogs

  • 서영거;정재경;구본암;조윤상
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1994.04a
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    • pp.215-215
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    • 1994
  • PGI$_2$ 안정한 구조를 갖는 carbaprostacyclin 및 그 structural analog들을 입체 선택적으로 합성하고, 혈관 순환 개선제로 발전시키고자 중요한 합성 중간체이며 광학활성을 갖는 5-ethenyl-3-hydroxy cyclopentane carboxylate를 합성하였다. 반응의 핵심 단계는 butyrolactone moiety를 갖는 allylic carbonate를 Pd(0)촉매하에서 환화시킨 후, 정교한desulfonation에 이온 lactone의 개열 단계를포함한다.

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CONVERGENCE THEOREMS FOR A PAIR OF ASYMPTOTICALLY AND MULTIVALUED NONEXPANSIVE MAPPING IN CAT(0) SPACES

  • AKKASRIWORN, NAKNIMIT;SOKHUMA, KRITSANA
    • Communications of the Korean Mathematical Society
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    • v.30 no.3
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    • pp.177-189
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    • 2015
  • In this paper, we prove ${\Delta}$-convergence theorems for Ishikawa iteration of asymptotically and multivalued nonexpansive mapping in CAT(0) spaces. This results we obtain are analogs of Banach spaces results of Sokhuma [13].

Synthesis of New Bicyclic Aziridines Containing Chalcone Analogs and Investigation of Their Photochromic Properties

  • Besharati-Seidani, Tayebeh;Mahmoodi, Nosrat O.
    • Bulletin of the Korean Chemical Society
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    • v.34 no.3
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    • pp.875-883
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    • 2013
  • Ten new derivatives of 1,3-diazabicyclo[3.1.0]hex-3-enes linked via ether linkage to chalcones were synthesized and characterized by UV, FT-IR, $^1H$ NMR and $^{13}C$ NMR spectral techniques. The spectra of all synthesized compounds, confirmed structure-photochromic behavior relationships (SPBR) both in solution or in solid state by irradiation under UV light at 254 nm. In other efforts for first time photochromic behavior of ketoaziridines has been investigated.

A Search for Endogenous Digitalis-like Factors (인체 및 고등 동물에서 생성되는 디기탈리스 유사체의 탐색)

  • 송영순
    • YAKHAK HOEJI
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    • v.30 no.4
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    • pp.198-201
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    • 1986
  • The successful elucidation of the opiate receptor and its natural ligands has generated speculation that other drugs might interact with cellular sites designed to accommodate endogenous mediators. The properties of binding sites for the cardiac glycosides(CG), together wit the potency and specificity of the digitalis drugs suggest that CG mimic an endogenous digitalis-like factor. Recenthy, several laboratories have reported the potency in mammalian tissues and fluids of unidentified materials that share certain specific propeties of the CG. Identification of body's own digitalis might yield a natural co pound whose synthetic analogs may provide safer and more effective drugs than can be achieved by structural edification of the CG of plant origin.

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A BUMPING ALGORITHM ON THE SHIFTED RIM HOOK TABLEAUX

  • Lee, Jae-Jin
    • Journal of applied mathematics & informatics
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    • v.6 no.3
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    • pp.901-914
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    • 1999
  • In [6] Schensted constructed the Schensted algorithm giving a bijection between permutations and pairs of Young standard tableaux. After knuth generalized it to column strict tableaux in [3] various analogs of the Schensted algorithm came. In this paper we describe the bumping algorithm on the shifted rim hook tableaux which is the basic building block of the Schensted algorithm for shifted rim book tableaux.