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The Synthesis of 6-Fluoroquinolone Carboxamidopenicillin Derivatives (6-Fluoroquinolone Carboxamidopenicillin 유도체의 합성)

  • 임철부;김정주
    • YAKHAK HOEJI
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    • v.31 no.2
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    • pp.92-97
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    • 1987
  • The N-[1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroquinoline-3-carboxy] succinimide was reacted with amoxicillin, ampicillin and 6-APA to give 6-[D-(-)-$\alpha$-{1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroguinoline-3-carboxamido} p-hydroxyphanyl acetamido] penicillanic acid [1], 6-[D-(-)-$\alpha$-{1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroquinoline-3-carboxamido} phenylacetamido] penicillanic acid [10] and 6-[1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroquinoline-3-carboxamido] penicillanic acid [19]. The 1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxylic acids were reacted with ethyl chloroformate for making mixed anhydride; these mixed anhydrides were reacted with amoxicillin, ampilcillin and 6-APA to give 6-[D-(-)-$\alpha$-{1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxamido} p-hydroxyphenylacetamido] penicillanic acid [2-9], 6-[D-(1)-$\alpha$-{1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxamido} phenylacetamidod penicillanic acid [11-18] and 6-[1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxamido] penicillanic acid [20-27].

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Reactions of 3-Alkylidene-2,4-pentanediones with Arylhydrazines (3-알킬리덴-2,4-펜탄디온과 아릴히드라진의 반응)

  • Se Young Lee;Seung Hoi Kim;Youn Young Lee;Yang Mo Goo
    • Journal of the Korean Chemical Society
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    • v.36 no.2
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    • pp.311-317
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    • 1992
  • Reaction of 3-alkylidene-2,4-pentanediones(1) with arylhydrazines in methanol afforded 4-acetyl-(2), 4-(1-methoxyalkyl)-(3), or 4-vinylpyrazole derivatives(4). 3-(2,2,2-Trichloroethylidene)-2,4-pentanedione(9) reacted with arylhydrazines to give 4-acetyl-1-aryl-3-methylpyrazoles(11). Possible mechanisms for these reactions were proposed.

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Design of Unified HEVC 4×4 IDCT/IDST Block (HEVC 4×4 IDCT/IDST 통합 블록 설계)

  • Jung, Seulkee;Lee, Seongsoo
    • Journal of IKEEE
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    • v.19 no.2
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    • pp.271-275
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    • 2015
  • This paper proposes a unified HEVC $4{\times}4$ IDCT/IDST architecture for area reduction. In general, $4{\times}4$ IDCT and $4{\times}4$ IDST blocks are implemented separately, and they are connected with multiplexers. In the proposed arechitecture, these two blocks are unified, and internal hardware resources such as multipliers are shared. This reduces the chip area. The synthesized block in 0.18 um technology is 2,795 gates, and the gate count is reduced by 9.44% in comparison with conventional designs.

An Efficient Synthesis of New Pyrazolines and Isoxazolines Bearing Thiazolyl and Etheral Pharmacophores

  • Bhosle, Manisha R.;Mali, Jyotirling R.;Pratap, Umesh R.;Mane, Ramrao A.
    • Bulletin of the Korean Chemical Society
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    • v.33 no.6
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    • pp.2012-2016
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    • 2012
  • A convenient synthetic route has been developed to synthesize 5-(4-((2-phenylthiazol-4-yl) methoxy)phenyl)-3-(4-sustituted phenyl)pyrazolines (5a-f) and 5-(4-((2-phenylthiazol-4-yl)methoxy)phenyl)-3-(4-substituted phenyl)isoxazolines (6a-f) starting from 2-phenyl-4-chloromethylthiazole (1). The chloromethylthiazole (1) was first condensed with 4-hydroxy benzaldehyde (2) for obtaining 4-((2-phenylthiazol-4-yl)methoxy)benzaldehyde (3). Claisen-Smidth condensation of 4-((2-phenylthiazol-4-yl)methoxy)benzaldehyde (3) and acetophenones has been carried in alkaline alcohol and obtained 3-(4-((2-phenylthiazol-4-yl)methoxy)phenyl)-1-(4-substituted phenyl)prop-2-en-1-ones (4a-f). The cyclocondensation of 2-propen-1-ones has been first time carried separately with hydrazine hydrate and hydroxylamine hydrochloride in aqueous micellar tetradecyltrimethylammonium bromide (TTAB) medium for getting the titled heterocycles with good to excellent yields.

Selective Acyl and Alkylation of Monobenzoyl p-tert- Buty1calix[4]arene

  • 김종민;전종철;남계춘
    • Bulletin of the Korean Chemical Society
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    • v.18 no.4
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    • pp.409-415
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    • 1997
  • Several calixarene derivatives of 5,11,17,23-tetra-tert-butyl-25-(3,5-dinitrobenzoyloxy)-26,27,28-trihydroxycalix[4]arene 2 were synthesized by the reaction of 2 with several acyl and alkylating agents in the presence of base such as pyridine and K2CO3 in THF. Acylation of monobenzoylated p-tert-butylcalix[4]arene 2 yielded their corresponding 1,3-diacylated calix[4]arenes 3a-3g. On the other hand, alkylation of 2 produced a variety calix[4]arene derivatives such as 1,2- and 1,3-disubstituted calix[4]arenes 4a-4c, 4e-4f, or 1,2,4-trisubstituted calix[4]arene 4d. 1,2-Disubstituted calix[4]arenes are chiral. All derivatives exist as a cone conformation based on NMR studies.

Molecular Switching Coordination Polymers. 4.4'-Chalcogenobispyridine Bridged Cobalt Benzoquinone Complexes

  • 조두환;정종화;여환진;손윤수;정옥상
    • Bulletin of the Korean Chemical Society
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    • v.16 no.6
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    • pp.504-507
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    • 1995
  • The reaction of Co2(CO)8 with 3,6-di-tert-butyl-1,2-benzoquinone in the presence of the respective 4,4'-chalcogenobispyridine results in the coordination polymers of [CoⅢ(4,4'-X(Py)2)(DBSQ)(DBCat)]n (X=S, Se, Te; Py=pyridine; DBSQ=3,6-di-tert-butylsemiquinone; DBCat=3,6-di-tert-butylcatechol). The title compounds undergo an intramolecular Cat → Co electron transfer, and thus change toward the [CoⅡ(4,4'-X(Py)2)(DBSQ)2]n at elevated temperature. The temperature-switching properties of the compounds directly depend upon the electronegativity of the chalcogen atom of the 4,4'-chalcogenobispyridine coligands. The spectroscopic data disclose that the properties of [CoⅢ(4,4'-S(Py)2)(DBSQ)(DBCat)]n and [CoⅢ(4,4'-Se(Py)2)(DBSQ)(DBCat)]n are similar each other in contrast to those of [CoⅢ(4,4'-Te(Py)2)(DBSQ)(DBCat)]n.

Expression of C4.4A is a Potential Independent Prognostic Factor for Patients with Gastric Cancer

  • Cheng, Da-Qing;Gu, Xiao-Dong;Li, Zhen-Yang;Xiang, Jian-Bin;Chen, Zong-You
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.9
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    • pp.3895-3899
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    • 2014
  • C4.4A, a metastasis-associated gene, encodes a glycolipid-anchored membrane protein which is overexpressed in several human malignancies. However, there are few data available on C4.4A expression and its relationship with progression in gastric cancer. Our study was designed to explore the expression of C4.4A in gastric cancer and to correlate it with clinical outcome. C4.4A expression was studied by quantitative real-time RT-PCR and immunohistochemistry for assessment of correlations with clinicopathological factors. C4.4A mRNA expression was significantly up-regulated in gastric cancer as compared with noncancerous tissue (p<0.05)., being observed in 107 (88.4%) of the 121 gastric cancer cases by immunohistochemistry. We found that the expression of C4.4A mRNA was correlated with size of the tumor, depth of invasion, lymph node metastasis, distant metastasis and TNM stage. Moreover, patients with overexpression of C4.4A has a significantly worse survival (p<0.05). Further multivariable analysis indicated that the expression of C4.4A was an independent prognostic indicator for gastric cancer (p<0.05). In conclusion, overexpression of C4.4A correlates with metastatic potential of gastric cancer and C4.4A could be a novel independent prognostic marker for predicting outcome.

Crystal growth and optical absorption of $Mg_{0.16}Zn_{0.84}Te:Co $ single crystal ($Mg_{0.16}Zn_{0.84}Te:Co $단결정 성장과 광흡수 특성)

  • 정상조
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.7 no.4
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    • pp.548-554
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    • 1997
  • The single crystal of $Mg_{0.16}Zn_{0.84}$Te:Co(Co:0.01 mole%) was grown by vertical Bridgman method. The crystal structure of $Mg_{0.16}Zn$_{0.84}$Te:Co and optical absorption properties of this compound were studied. The grown single crystal has a cubic structure and a lattice constant a=6.1422 $\AA$ were determined by X-ray diffraction. As a result of the optical absorption spectra of $Mg_{0.16}Zn_{0.84}$Te:Co, the intracenter transitions due to $Co^{2+}$ ions were detected for $A-band:^4A_2(^4F){\to}^4T_2(^4F),\; B-band:^4A_2(^4F){\to}^4T_1(^4F), C- band:^4A_2(^4F){\to}^4T_1(^4P)$.The charge transfer transition near the absorption edge was observed in the wavelength range of 550 to 770 nm. According to the crystal field theory, the crystal field parameter(Dq) and the Racah parameter(B) were determined.

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The Synthesis of 6-[1-(4-Ribitylanilino)ethyl]-1,3-dimethyllumazine Related to Methanopterin (Methanopterin과 관련된 6-[1-(4-Ribitylanilino)ethyl]-1,3,7-trimethyllumazine의 합성)

  • Jang, Yong Jin;Kim, Yeon Hee;Kang, Yong Han
    • Journal of the Korean Chemical Society
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    • v.43 no.6
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    • pp.670-675
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    • 1999
  • 6-[1-(4-Ribitylanilino)ethyl]-1,3,7-trimethyllumazine (2), which is related to pteridine moiety of methanopterin, was synthesized. 4-Ribitylaniline derivative was prepared from D-ribose and N-benzoyl-4-bromoaniline (7) as the starting materials through several steps. 6-Acetyl-1,3,7-trimethyllumazine (4) was obtained from the reaction of 4-amino-1,3-dimethyI-5-nitrosouracil (3) with 2,4-pentanedione by Timmis reaction. Compound 4 was converted to 6-(1-chloroethyl)-1,3,7-trimethyllumazin (6) by the reduction with sodium borohydride and followed by chlorination with thionyl chloride. The nucleophilic displacement reaction of compound 6 with 4-(2,3:4,5-di-O-iso-propylidene-D-ribityl)aniline (13) in anhydrous DMF yielded 6-[1-{4-(2,3:4,5-di-O-isopropylidene-D-ribityl)anilino}ethyl]-1,3,7-trimethyllumazine (14). The target molecule 2 was obtained by the hydrolysis of compound 14 in the presence of an acid catalyst.

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Microwave dielectric properties of $(1-x)CaWO_4-xYNbO_4$ ceramics ($(1-x)CaWO_4-xYNbO_4$계 세라믹스의 마이크로파 유전특성)

  • Kim, Su-Jung;Kim, Eung-Soo
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.17 no.5
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    • pp.217-222
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    • 2007
  • Microwave dielectric properties of $(1-x)CaWO_4-xYNbO_4$ ceramics have been investigated as a function of $YNbO_4$ content($0.05{\leq}x{\leq}0.4$). A single phase with tetragonal scheelite structure was obtained up to x=0.10 and then the secondary phase with fergusonite structure was increased. With the increase of $YNbO_4$ content, apparent densities of the specimens were decreased. This results were due to the lower theoretical density of $YNbO_4(5.581g/cm^3)$ than that of $CaWO_4(6.117g/cm^3)$. Dielectric constant(K) and quality factor(Qf) were decreased with $YNbO_4$ content which could be attribute to the decrease of density and the increase of secondary phase. Temperature coefficient of resonant frequency (TCF) of the specimens with the $YNbO_4$ content was depended on dielectric mixing rule.