• Archives of Pharmacal Research
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• 제26권2호
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• pp.107-113
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• 2003

Several fused triazolo and ditriazoloquinoxaline derivatives such as 1-aryl-4-chloro-[1,2,4]triazolo[4,3-a]quinoxalines (3a-d), 4-alkoxy[1,2,4]triazolo[4,3-a]quinoxalines (4a,b), 4-substituted-amino-[1,2,4] triazolo[4,3-a]quinoxalines (5a-h), 1-(aryl)-[1,2,4]triazolo[4,3-a]quinoxalin-4(5H)-thione (6), 4-(arylidenehydrazino )-1-phenyl-[1,2,4]triazolo[4,3-a]quinoxalines (10a-e) and [1,2,4]ditriazolo[4,3-a:3',4'-c]quinoxaline derivatives (11-13) have been synthesized and some of these derivatives were evaluated for antimicrobial and antifungal activity in vitro. It was found that compounds 3a and 9b possess potent antibacterial activity compared to the standard tetracycline.

• Bulletin of the Korean Chemical Society
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• 제23권6호
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• pp.856-861
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• 2002

The general reducing charagteristics of a newly synthesized reducing agent, lithium(2.3-dimethyl-2-butyl)-${\iota}$-butoxyborohydride (Li $Thx'BuOB_2$, 1), in tetrahydrofuran (THF) toward selected organic compounds containing representative fundtional groups under practical has been examined. The reagent revealed an interesting and unique reducing characteristics. Especially, the stereoselectivity in the reduction of cyclic ketones was extraordinary. Thus, the introduction of bulky alkyl and alkoxy groups into the parent borohydride affonds a high stereoselectivity. In general, the reducing power of the reagent is somewhere between the dialiylborohydride and the parent borohydride. This permits the reagent to be a reagent of choice for selecitive reduction of organic compounds with an improved selectivity.

• 농약과학회지
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• 제3권2호
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• pp.90-93
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• 1999

Several vinylsulfonylphenyl triketones and 2-alkoxy- and 2-(N,N-diethylamino) ethanesulfonylphenyl triketones have been synthesized, and their herbicidal activities in flooded paddy field were studied. Herbicidal effects of vinylsulfonyl triketones 6a-c were not satisfactory, whereas 2-alkoxyethanesulfonylphenyl triketones 7a and 7b showed good herbicidal activities without meaningful selectivity to rice.

• Archives of Pharmacal Research
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• 제28권2호
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• pp.129-141
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• 2005

(-)-Fumagillol (1), a hydrolysis product of fumagillin, has been synthesized by several group from commercially available 1,2:5,6-di-O-isopropylidene-${\alpha}$-D-allofuranose in a highly stereoselective manner. Chiral centers on C5 and C6 came from D-allofuranose and the asymmetric center on C4 was accomplished by 1,3-chirality transfer using the Claisen rearrangement on a chiral allyl alcohol. Chirality, which is necessary on an epoxide consisting of the spiro-ring system, was diastereoselectively constructed by the well-known reaction, intramolecular ester enolate alkylation (IEEA), which showed that this reaction can be applied to the alpha-alkoxy ester system. The epoxide on the side chain was regioselectively introduced by the difference between the number of substituents on the vinyl groups. This accomplishment proved that IEEA can be a useful tool for the synthesis of complex molecules.

• 대한화학회지
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• 제17권6호
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• pp.391-394
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• 1973

반실험적인 양자역학 이론인 extended Huckel theory를 nitroaniline, 1-methoxy-4-nitroaniline과 1-ethoxy-4-nitroaniline에 적용하여 정량적으로 변화하는 sweetness기구를 구명코져 nitroaniline을 coplanar로 두고 ortho치환체의 geometrical rotation을 시켰을 때 charge density와 sweetness와의 상관관계를 설명하였다.

• 대한화학회지
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• 제48권6호
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• pp.609-615
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• 2004

간염치료에 탁월한 효과를 나타내는 alkoxyallylthiopyridazine 유도체들이 maleic anhydrides로부터 합성되었다. 수용성 HCl에서 maleic anhydrides를 hydrazine monohydrate로 환류하면 dihydroxypyridazines이 얻어지며, 이 화합물을 phosphorus oxychloride로 반응시키면 dichloropyridazines으로 전환되었다. Dichloropyridazines에서 첫 번째 염소원자의 치환은 THF 용매에서 알코올성 sodium alkoxides에 의하여 선택적으로 일어나 alkoxy- chloropyridazines을 생성하며, 이 화합물은 lithium 2-propene-1-thiolate에 의하여 높은 수득율로 alkoxyallyl- thiopyridazines으로 전환되었다.

• 약학회지
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• 제39권6호
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• pp.631-635
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• 1995

A series of 3, 4-dihydro-3-oxo-2H-1, 2, 4-benzothiadiazine-1, 1, dioxides with cytotoxic activity against human solid tumors is described. Synthesized compounds showed mild but broad spectrum cytotoxicity in vitro. The lipophilic substituents like alkyl, alkoxy and chloro on benzene ring increased the activity. Also hydrophobic group on 3 or 4 position of benzothiadiazine was important for the activity.

• Archives of Pharmacal Research
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• 제29권5호
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• pp.394-399
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• 2006

Benzothiazole derivatives of thiazolidinediones (TZD) were synthesized using a modified Mitsunobu reaction of 2-(benzothiazol-2-ylmethylamino)ethanol (2) with 5-(4-hydroxybenzyl)-3-triphenylmethylthiazolidine-2,4-dione and assayed for activity on peroxisome proliferator-activated receptor (PPAR) subtypes and inhibitory activity of NO production in lipopolysaccharide-activated macrophages. Most of the tested compounds were identified as potent $PPAR_\gamma$ agonists, indicating their potential as drug candidates for diabetes.

• 한국막학회:학술대회논문집
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• 한국막학회 2003년도 The 4th Korea-Italy Workshop
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• pp.47-50
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• 2003

Carbon-silica membranes were Prepared by Pyrolyzing polyimide/silica composite obtained from ill-situ polymerization of alkoxy silanes via sol-gel reaction. In this study, effects of silica content and silica network in polyimide matrix were focused on the gas permeation and separation properties of the final carbon-silica membrane. The membranes prepared were characterized with a field emission scanning electron microscopy (FE-SEM), a solid state $^{29}$ Si nuclear magnetic resonance spectroscopy ($^{29}$ Si-NMR), an electron spectroscopy for chemical analysis (ESCA), a thermogravimetric analysis (TGA) and gas permeation tests.

• Journal of Photoscience
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• 제11권3호
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• pp.101-106
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• 2004

The photorefractive composites fabricated by blending NLO chromophores such as 3-(4-{bis-[4-(2-ethylhexyloxy)-phenyl]-amino}-phenyl)-2-isocyano-acrylonitrile (PAIA), bis-[4-(2-ethyl-hexyloxy)-phenyl]-{4-[2-(4-nitrophenyl)-vinyl]-phenyl}-amine (PNPA) with photoconducting crosslinkable matrix, bis-(4-ethynylphenyl)-(4-octyloxyphenyl)-amine (BEOPEA), showed photorefractive property due to the high composition of NLO chromophores caused by introducing alkoxy chain, and many problems faced in typical organic photorefractive systems such as timeconsuming chemical synthesis, difficulty in rational design, intrinsic instability and phase separation could be avoided.