• Bulletin of the Korean Chemical Society
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• 제18권8호
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• pp.890-895
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• 1997

The approximate rates and stoichiometry of the reaction of excess lithium tripiperidinoaluminum hydride (LTPDA), an alicyclic aminoaluminum hydride, with selected organic compounds containing representative functional groups under the standardized conditions (tetrahydrofuran, 25°) were examined in order to define the reducing characteristics of the reagent for selective reductions. The reducing ability of LTPDA was also compared with those of the parent lithium aluminum hydride (LAH) and lithium tris(diethylamino)aluminum hydride (LTDEA), a representative aliphatic aminoaluminum hydride. In general, the reactivity of LTPDA toward organic functionalities is weaker than LTDEA and much weaker than LAH. LTPDA shows a unique reducing characteristics. Thus, benzyl alcohol, phenol and thiols evolve a quantitative amount of hydrogen rapidly. The rate of hydrogen evolution of primary, secondary and tertiary alcohols is distinctive. LTPDA reduces aldehydes, ketones, esters, acid chlorides and epoxides readily to the corresponding alcohols. Quinones, such as p-benzoquinone and anthraquinone, are reduced to the corresponding diols without hydrogen evolution. Tertiary amides and nitriles are also reduced readily to the corresponding amines. The reagent reduces nitro compounds and azobenzene to the amine stages. Disulfides are reduced to thiols, and sulfoxides and sulfones are converted to sulfides. Additionally, the reagent appears to be a good partial reducing agent to convert primary carboxamides into the corresponding aldehydes.

• Bulletin of the Korean Chemical Society
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• 제28권9호
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• pp.1510-1514
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• 2007

Recently, it has been reported that the inhibition of the strand transfer function of HIV-1 integrase is necessary to obtain significant antiviral activity. Accordingly, several compounds typified by aryl 1,3-diketo acids that can inhibit strand transfer reaction of HIV-1 IN have been identified. In this work, we synthesized new 4- hydroxy-5-azacoumarin-3-carbox(thio)amides (1a-h) and evaluated for the inhibition of HIV-1 IN strand transfer reaction with a brief SAR. Among synthesized, compound 1e was the most potent HIV-1 IN inhibitor with equipotent activity to that of L-708,906. Therefore, the 4-hydroxy-5-azacoumarin ring can be considered as a new scaffold in designing more potent of HIV-1 IN inhibitors for treatment of AIDS.

• Bulletin of the Korean Chemical Society
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• 제14권4호
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• pp.469-475
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• 1993

The approximate rates and stoichiometry of the reaction of excess lithium tris(diethylamino)aluminum hydride (LTDEA) with selected organic compounds containing representative functional groups under standardized condition (tetrahydrofuran, 0$^{\circ}C$) were examined in order to define the characteristics of the reagent for selective reductions. The reducing ability of LTDEA was also compared with those of the parent lithium aluminum hydride (LAH) and lithium tris(dibutylamino)aluminum hydride (LTDBA). In general, the reactivity toward organic functionalities is in order of LAH${\gg}$LTDEA${\geq}$LTDBA. LTDEA shows a unique reducing characteristics. Thus, benzyl alcohol and phenol evolve hydrogen slowly. The rate of hydrogen evolution of primary, secondary, and tertiary alcohols is distinctive: 1-hexanol evolves hydrogen completely in 6 h, whereas 3-hexanol evolves hydrogen very slowly. However, 3-ethyl-3-pentanol does not evolve any hydrogen under these reaction conditions. Primary amine, such as n-hexylamine, evolves only 1 equivalent of hydrogen. On the other hand, thiols examined are absolutely inert to this reagent. LTDEA reduces aldehydes, ketones, esters, acid chlorides, and epoxides readily to the corresponding alcohols. Quinones, such as p-benzoquinone and anthraquinone, are reduced to the corresponding diols without hydrogen evolution. However, carboxylic acids, anhydrides, nitriles, and primary amides are reduced slowly, where as tertiary amides are readily reduced. Finally, sulfides and sulfoxides are reduced to thiols and sulfides, respectively, without evolution of hydrogen. In addition to that, the reagent appears to be an excellent partial reducing agent to convert esters, primary carboxamides, and aromatic nitriles into the corresponding aldehydes. Free carboxylic acids are also converted into aldehydes through treatment of acyloxy-9-BBN with this reagent in excellent yields.

• Applied Biological Chemistry
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• 제44권3호
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• pp.191-196
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• 2001

새로운 살균제 농약 개발을 목적으로 삼불화메틸기 디히드로-1,4-옥사티인기가 포함된 ${\alpha},{\beta}$-불포화 카르복스아미드 유도체 5를 합성하였다. 삼불화 ${\beta}$케토에스테르 유도체 6을 염화한 다음 1,2-메르캡토에탄을과 반응시켜 중간체 1,4-옥사티안 유도체 11을 얻었다. 중간체 11의 정제없이 히드록시기를 염소로 치환한 다음 중간체 10을거쳐 트리에틸 존재하에서 탈염화하여 삼불화메틸기가 포함된 디히드로-1,4-옥사티인 에틸에스테르 9를 합성하였다. 에스테르 9를 가수분해하여 생성된 카르복실산 12의 히드록시기를 염소로 치환하여 활성화한 다음 여러 가지 아민 유도체와 반응시켜 삼불화메틸기가 포함된 디히드로-1,4-옥사티인 카르복스아미드 유도체 5를 합성하였다. 합성된 화합물을 대표적인 6종의 식물병원균, 벼 도열병, 벼 잎집무의마름병, 오이 잿빛곰팡이병, 토마토 역병, 밀 붉은 녹병, 그리고 보리 흰가루병 등에 대한 in vivo 항균력을 시험하였다. 그 결과, 페닐기의 meta 위치에 이소프로폭시기 또는 이소프로필기가 치환된 화합물이 벼 잎집무의마름병과 밀 붉은녹병에 대한 강한 항균력을 나타냈다.