• 제목/요약/키워드: Synthesis.

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Adenine, new anti-wrinkle agent.

  • Kim, Y. J.;Kim, Y. S.;S.Y. Eom;Kim, J. H.
    • 대한화장품학회:학술대회논문집
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    • 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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    • pp.804-819
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    • 2003
  • It has been known that adenine is a very important material in living cells. Because, adenine is a member of nucleotide base, so it takes part in DNA, RNA and ATP synthesis. There are many reports that adenine participated in ingredients, especially DNA, RNA, NADH and ATP, affect on the cell. As well adenosine, conjugated adenine to glycoside, was known to anti-wrinkle compound. But there is no report whether adenine shows a good effect on the skin, especially anti-wrinkle. So, in this study, we tested whether adenine affects cell proliferation, collagen synthesis, collagenase synthesis inhibition in human dermal fibroblasts. In addition, we performed clinical study with adenine cream. Cell proliferation effect was tested by MTT assay. Collagen and collagenase synthesis were measured by Immunoassay with ELISA kit. Clinical study was performed by IECK according to KFDA Functional Cosmetic method. The results of cell proliferation show that 10$^{-6}$ ~10$^{-8}$ % of adenine increases cell proliferation about 50 % compare with non-treated control. At 10$^{-7}$ ~10$^{-10}$ %, adenine increases type I collagen synthesis about 50%, decreases type I collagenase about 22% compare with non-treated control. The results of clinical study show that 0.05% adenine treated group reduces wrinkle significantly compare with placebo treated group. Therefore adenine may be a new anti-wrinkle candidate, through increases cell proliferation and collagen synthesis dramatically. And it decreases collagenase synthesis. So adenine could be used as a new anti-wrinkle agent.

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부분구조합성법을 이용한 판의 모우드해석 (Modal Analysis of Plate by Substructure Synthesis Method)

  • 정재훈;지태한;박영필
    • 한국정밀공학회지
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    • 제11권6호
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    • pp.65-74
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    • 1994
  • Various substructure synthesis methods, such as component mode synthesis, building block analysis and reduced impedance method, are studied for the determination of vibration characteristics of plate problems. Comparisons are made for each methods in terms of accuracy and computational efficiency. Following conclusions are made from the results of computer simulations and experiments. i) The computation time of component mode synthesis is much shorter than that of whole structure analysis. The natural frequencies of lower modes obtained from component mode synthesis are almost same as those obtained from whole structure analysis, but in higher modes the differences between those two methods are increases. ii) The transfer function obtained from building block analysis is same as that obtained from the finite element method. iii) Same transfer functions can be obtained by the reduced impedance method. The computation time of reduced impedance mathod is shorter that that of general finite element method, but for the solutions in broad frequency band it requires long calculation time.

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디아조크로마논과 보론산의 팔라듐 촉매하 결합반응을 이용한 Lespedezol $A_1$의 합성 (Formal Synthesis of Lespedezol $A_1$ via Versatile Palladium-Catalyzed Cross-Coupling of Diazochromanone with Arylboronic Acid)

  • 한영택
    • 약학회지
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    • 제57권5호
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    • pp.357-361
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    • 2013
  • A formal synthesis of Lespedezol $A_1$ has been accomplished. The key feature of this synthesis involves an efficient and powerful palladium-catalyzed cross coupling reaction of diazocarbonyl compound with bis(benzyloxy)phenylboronic acid for the key 3-aryl-chromen-4-one intermediate, which was difficult to be prepared by Suzuki coupling reaction in the previous study. The versatile and efficient synthetic procedure would facilitate synthesis of pterocarpenes and their derivatives.

Synthesis of Halicylindramide A Mimetics Containing Lactone Isosteres

  • Yeo, Sang-Hyuk;Seo, Hyun-Ju;Lim, Dong-Yeol
    • Bulletin of the Korean Chemical Society
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    • 제32권spc8호
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    • pp.2916-2920
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    • 2011
  • Synthesis of halicylindramide A mimetics via solid-phase peptide synthesis is described. The N-Me-Gly-Thr residues in halicyclindramide A has been replaced by N-Me-Gly-Dpr, Lys, or N-Me-Gly-allo-Thr. Solution structures of the mimetics were compared by CD spectroscopy in an aqueous buffer and in TFE.

형태합성에 의한 새로운 6 절 기구 로보트 손의 개념설계 (Conceptual Design of New Six-Bar Robot Hand by Type Synthesis)

  • 이경원;이황진
    • 한국정밀공학회지
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    • 제17권6호
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    • pp.63-68
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    • 2000
  • This paper describes the conceptual design of new robot hand by type synthesis. The conventional robot hands with rotational movement have bad controllability because the distance between the final rotational joint and the center of things grasped is changed according to the size of things grasped. This paper uses the systematic procedure of type synthesis and the knowledge for designing robot hands. The new 6-bar Watt I type conceptual robot hand with rectilinear translational movement is proposed.

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자전 고온 반응 합성법을 이용한 NiTi계 형상기억 합금의 제조에 관한 연구 (Processing of NiTi Shape Memory Alloy by Self- propagating High-temperature Synthesis)

  • 윤종필
    • 한국분말재료학회지
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    • 제2권2호
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    • pp.158-164
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    • 1995
  • Synthesis of the NiTi shape memory alloy using the thermal explosion mode of the self-propagating high-temperature synthesis has been investigated. The significant fractions of intermetallics phases were found to form at the Ti/Ni powder interface during the heating to the ignition temperature and seemed to influence the relative fraction of phases in the final products. As the heating rate to the ignition temperature was increased, the combustion temperature and the fraction of NiTi in the final reaction products were increased. The synthesis reaction under 70 MPa compressive pressure yielded a reaction product with 98% theoretical density.

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Solid Phase Synthesis of 3-(4-Hydroxyphenyl)coumarin: Preliminary Experiments for Combinatorial Synthesis of Substituted 3-Phenylcoumarin Derivatives

  • Bae, Hoon;Kim, Hak-Sung
    • Archives of Pharmacal Research
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    • 제27권8호
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    • pp.811-815
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    • 2004
  • Coumarin and its derivatives occur widely in nature. Many attempts were made for synthesis of various coumarin derivatives because of their interesting biological activities. In this study, solid phase synthetic approach of 3-(4-hydroxyphenyl)coumarin was achieved for combinatorial synthesis of substituted 3-phenylcoumarin analogues. Starting from 4-hydroxyphenylacetic acid methyl ester, release of 3-(4-hydroxypnehyl)coumarin from polymer support was accom-plished.

Novel Asymmetric Synthesis of Unsaturated 1,2-Amino Alcohols

  • Kim, Ji-Duck;Jung, Young-Hoon
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.231.2-232
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    • 2002
  • The synthesis of chiral 1,2-amino alcohols has been an area of intense study in the synthetic and industrial fields, because of their important roles in organic synthesis as fundamental building blocks and their occurrence in a number of natural products. drugs. and chiral auxiliaries or ligands. General methods for the synthesis of these compounds can be divided into two large categories: functional group transformations and the C-C or the C-N bond formations. (omitted)

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비동기회로 합성을 위한 병행 프로그램의 페트리 넷으로의 변환 (Translating concurrent programs into petri nets for synthesis of asynchronous circuits)

  • 유동훈;이동익
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1998년도 하계종합학술대회논문집
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    • pp.883-886
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    • 1998
  • We introduce a high level synthesis methodlogoy for automatic synthesis of asynchronous circuits form a language based on CSP. The input language is a high level concurrent algorithmic specification that can model complex concurrent control flow, logical and arithmetic computation and communications between them. This specification is translated into petri net which has actions. These actions are refined to synthesize the controllers and to allocate the data resources. We use the automatic synthesis through signal transition graphs (STGs) that allows to take advantage of logic synthsis methods to optimize the circuit.

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