• 제목/요약/키워드: Practical synthesis

검색결과 282건 처리시간 0.026초

A Practical Synthesis of Morita-Baylis-Hillman Adducts of Aryl Vinyl Ketones Catalyzed by a Proton Donor

  • Kim, Sung-Hwan;Kim, Se-Hee;Lim, Cheol-Hee;Kim, Jae-Nyoung
    • Bulletin of the Korean Chemical Society
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    • 제33권6호
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    • pp.2023-2027
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    • 2012
  • An efficient and practical synthesis of MBH adducts of aryl vinyl ketones was developed using DABCO and 4-nitrophenol as a proton donor. Addition of a proton donor and the use of excess amounts (3.0 equiv) of aldehydes were highly beneficial for the yields of MBH adducts of aryl vinyl ketones.

A Practical Synthesis of (Z)-7-Eicosen-11-one and (Z)-7-Nonadecen-11-one, the Pheromone of Peach Fruit Moth, and Its Biological Activity Test

  • Suck-Ku Kang;Jung-Min Park;Jung-Han Kim;Hyun-Gwan Goh
    • Bulletin of the Korean Chemical Society
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    • 제4권2호
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    • pp.61-63
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    • 1983
  • A new practical method is described for the synthesis of (Z)-7-eicosen-11-one (1) and (Z)-7-nonadecen-11-one (2), the active principles of the sex pheromone of the peach fruit moth. Lithium anion of 1-octyne (from acetylene and 1-bromohexane) was alkylated with 3-bromo-1-propanol tetrahydropyranyl ether and deprotected to afford 4-undecyn-1-ol, which was oxidized with pyridinium chlorochromate to 4-undecyn-1-al. 4-Undecyn-1-al was treated with 1-nonylmagnesiumbromide or 1-octylmagnesiumbromide to yield 7-eicosyn-11-ol and 7-nonadecyn-11-ol. Jones oxidation, followed by Lindlar catalytic hydrogenation afforded the target compounds. Biological activity of the synthetic pheromones as attractants for males of the peach fruit moth was tested in the field using polyethylene capsules as containers. For each vial containing about 3.0 mg of the synthetic pheromone, the number of trapped moths were counted.

NETLA Based Optimal Synthesis Method of Binary Neural Network for Pattern Recognition

  • Lee, Joon-Tark
    • 한국지능시스템학회논문지
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    • 제14권2호
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    • pp.216-221
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    • 2004
  • This paper describes an optimal synthesis method of binary neural network for pattern recognition. Our objective is to minimize the number of connections and the number of neurons in hidden layer by using a Newly Expanded and Truncated Learning Algorithm (NETLA) for the multilayered neural networks. The synthesis method in NETLA uses the Expanded Sum of Product (ESP) of the boolean expressions and is based on the multilayer perceptron. It has an ability to optimize a given binary neural network in the binary space without any iterative learning as the conventional Error Back Propagation (EBP) algorithm. Furthermore, NETLA can reduce the number of the required neurons in hidden layer and the number of connections. Therefore, this learning algorithm can speed up training for the pattern recognition problems. The superiority of NETLA to other learning algorithms is demonstrated by an practical application to the approximation problem of a circular region.

Recemization of L-Lysine for Pharmaceutical Synthesis and its Chiral Separation by GC-MS Spectroscopy

  • Cheong, Jae-Yeon;Choi, Su-Hang;Nam, Tae-Woo;Shin, Jae-Young;Kim, Su-Woong;Jung, Won-Tae
    • Archives of Pharmacal Research
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    • 제18권2호
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    • pp.69-74
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    • 1995
  • In order to improve physico-chemical properties and to enhance stability of drugs, amino acid salt has been widely adoptd in pharmaceutical synthesis. Acetylsalicylic acid lysinate is one of the widely used analgesics and it is a good example of t5his synthesis. In the case of bacetylsalicylic acid lysinate synthesis, racemization of natrually occurred lysine is esential because the racemic lysine salt of the drug shows better yield, crystallinity and dryness than that of the L-lysine salt. To esatablish a simple, practical and economical process for L-lysine racemization, L-lysine treatments with phosphoric acid and with acetic acid were compared and the optimum conditions for its process and derivatization were investigated by chiral separation methods using GC_MS spectroscopy.

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TLS를 이용한 QFT의 이득-위상 루프형성법 (A Gain-Phase Loop Shaping Method of QFT using TLS)

  • 김주식;정수현
    • 전기학회논문지P
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    • 제51권2호
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    • pp.94-98
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    • 2002
  • QFT(Quantitative Feedback Theory) is a very practical design technique that emphasizes the use of feedback for achieving the desired system performance tolerances in despite of plant uncertainty and disturbance. The gain-phase loop shaping procedure of QFT is employed to design controller, until the bounds at desired frequencies are satisfied. This paper presents a transfer function synthesis using TLS(Total Least Squares) and offers a loop shaping method with the suggested technique. An example illustrates a feasibility of the presented algorithm.

파이프라인형 데이타패스 합성을 위한 스케쥴링 기법 (A Scheduling Technique for Pipelined Datapath Synthesis)

  • 이근만;임인칠
    • 전자공학회논문지A
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    • 제29A권4호
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    • pp.74-82
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    • 1992
  • This paper deals with the scheduling problems, which are the most important subtask in High-level Synthesis. ILP(integer linear programming) formulations are used as a scheduling problem approach.For practical application to digital system design, we have concentrated our attentions on pipelined datapath scheduling. For experiment results, we choose the 5-th order digital wave filter as a benchmark and do the schedule. Finally, we can obtain better and near-optimal scheduling results.

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