Diethyl 3,4,5, - Trimethoxybenzylmalonate의 새로운 합성법

李茶浩,李英行,李晩求,蔡奎允 圓光大學校 1984 論文集 Vol.18 No.2

3,4,5 - Trimethoxybenjoyl chloride 와 diethyl malonate를 축합시키고 이어서 염소화반응 및 수소화반응에 의하여 70%의 수득률로서 diethyl 3,4,5 - trimethoxybenzylmalonate를 얻었다. direct condensation of 3,4,5 - trimethoxybenzoyl chloried with diethyl malonate followed by chlorination and hydrogenation afforded diethyl 3,4,5 - trimethoxybenzylmalonate in 70% overall yield.

1-Chloro-1-phenyl-2-carboethoxy-2-cyanoethene 유도체에 대한 thioglycolic acid 치환제의 합성

이영행,이채호,이갑상,이만구 圓光大學校 1984 論文集 Vol.18 No.2

The substitution products of thioglycolic acid to the derivatives of 1-chloro-1-phenyl-2-carboethoxy-e-cyano ethene synthesized 1-Chloro-1-phenyl-2-carboethoxy-2-cyanoethene [Ⅴ], 1-chloro-10(4-chlorophenyl)-2-carboethoxy-2-cyanoethene[Ⅳ] and 1-chloro-1-(4-methoxyphenyl)-2-carboethoxy-2-cyanoethene[Ⅶ] undergo substitution reactions with thioglycolic acid to form s-[(1-phenyl-2-carboethoxy-2-cyano) ethenyl]-thioglycolic acid s-[(1-(4-chlorophenyl)-2-carboethoxy-e-cyano] ethenyl]-thioglycolic acid and s-[1-(4-methoxyphenyl)-2-carboethoxy-2-cyano] ethenyl]-thioglycolic acid, respectively. The structure of products were identified by elemental analysis, potentiometric titration, infrared and nmr spectra.

상아질 접착제가 상아질 변연누출에 미치는 영향

채수경,김미자,이광원,손호현 全北大學校 齒醫學硏究所 1991 전북치대논문집 Vol.9 No.1

The purpose of this study was to evaluate the effect of various dentin adhesives on the incisal and gingival marginal leakage of class Ⅴ cavity. V-shape cavities with enamel bevel (0.7-1㎜) were prepared on the faciocervical area of 72 extracted human anterior teeth. Gingival margin of cavities was placed on dentin or cementum. Including 1 group with no dentin treatment, they were divided into 6 groups according to dentin surface treatment with Scotchprep(3M Co.), Prisma Universal Bond 2(Dentsply Inter. Inc.), Gluma(Cloumbus/Bayer), All BOND 2(Bisco inc.) and Denthesive(Kulzer Co.). After dentin treatment, Dentin adhesive(3M Co.) was applied on the treated dentin surface and Silux("U" shade, 3M Co.) was filled and polished. Dye penetration technique using 2% methylene blue solution was adopted to assess incisal and gingival marginal leakage. The following results were obtained 1. The degree of incisal marginal leakage in the non-treated group was greater than that in other groups(p<0.01), and incisal marginal leakage in the groups treated with All BOND 2, and Denthesive was less than that in the group treated with Gluma(P<0.01). 2. Incisal marginal leakage in the groups treated with Prisma Universal Bond 2, and Scotchprep was less than that in the group treated with Gluma(p<0.01). 3. Incisal marginal leakage among the groups treated with Scotchprep, Prisma Universal Bond 2, All BOND 2 and Denthesive was not different(p>0.05). 4. The degree of gingival marginal leakage in the non-treated group was significantly greater than that in other groups(p<0.01). 5. Gingival marginal leakage among the groups treated with Scotchprep, Prisma Universal Bond 2, Gluma, All BOND 2, and Denthesive was not statistically significant(p>0.05). But gingival marginal leakage was significantly less in the All BOND 2 treated group compared with Gluma treated group(p<0.05).

2,4-Diamino-5-(3´, 4´, 5´-trimethoxybenzyl) pyrimidine의 합성에 관한 연구

李寀浩 圓光大學校 基礎自然科學硏究所 1984 基礎科學硏究誌 Vol.3 No.1

The reactions of β-morpholino-α-3,4,5-trimethoxybenzylacrylonitrile with p-substituted aniline followed by cyclization affored 2,4-diamino-5-(3', 4', 5'-trimethoxybenzyl) pyrimidine in 85∼95% overall yield.

새로운 의약품의 합성에 관한 연구 : 6-Thiocyanopenicillanic Acid 유도체의 합성

李英行,李寀浩,崔元植 원광대학교기초자연과학연구소 1992 基礎科學硏究誌 Vol.11 No.3

6-Aminopenicillanic acid의 diazo화 반응과 sodium thiocyanate와 반응으로 새로운 β-lactam 화합물인 6-thiocyanopenicillanic acid(1a)를 합성하고 p-nitrobenzyl bromide, chloromelthylpivalate 및 1-chlorodiethylcarbonate들과의 반응에 의해 각각에 해당하는 ester(1b~d)를 합성하였다. A new β-lactam compound, 6-thiocyanopenicillanic acid(1a) was prepared by the reaction of diawnium salt of 6-aminopenicillanic acid with sodium thiocyanate. Reaction of 6-thiocyanopenicillanic acid(la) with p-nitrobenzyl bromide, chloromethylpivalate and l-chlorodiethylcarbonate, respectively, afforded the corresponding esters(1b~d).

Trimethoprim 중간체의 합성에 관한 연구(II) : Diethyl 3,4,5-trimethoxybenzylmalonate의 합성 The Synthesis of Diethyl 3,4,5-trimethexybenzylmalonate

李寀浩,李英行 圓光大學校 1982 論文集 Vol.16 No.2

Trimethoprim은 그람음성균과 변형균에 대하여 광범위한 항균력을 가진다. Trimethoprim은 흔히 3,4,5-trimethoxybenzaldelyde를 출발물질로 사용하여 합성되며 그 합성자체가 복잡하고 어려운 점이 많다. 이러한 어려운 점을 피하기 위하여 3,4,5-trimethoxybenzoic acid를 출발물질로 사용하였으며 그의 acid chloride와 ethyl cyanoacetate나 diethyl malonate를 축합시켜서 Trimethoprim의 중간체인 diethyl 3,4,5-trimethoxybenzolymalonate와 diethyl 3,4,5-trimethoxybenzylmalonate를 합성하였다. Trimethoprim has a moderately broad antibacterial spectrum which includes many of the gram-negative species. This compound has always been synthesized starting from 3,4,5-trimethoxy benzaldebyde, but the synthesis of the starting material itself were very complicated and tedious. To avoid these difficulties, we used 3,4,5-trimethoxybenzoic acid as starting material and attempted to condense ethyl cyanoacetate and diethyl malonate with 3,4,5-trimethoxybenzoyl chloride. As a result, the intermediates for the synthesis of trimethoprim, diethyl 3,4,5-trimethoxybenzoylmalonate and diethyl 3,4,5-trimethoxybenzylmalonate were synthesized.

α-Methyl Dl-N-Benzylaspartate의 합성

이채호,조성동,이만구,채규윤 圓光大學校 基礎自然科學硏究所 1987 基礎科學硏究誌 Vol.6 No.1

Synthesis of α-methyl N-benzylaspartates from DL-aspartic acid is described. DL-Aspartic acid was transformed in several ways into DL-aspartic anhydride which was subjected to alcoholysis in methanol. Benzylation of the resulting a-methyl DL-aspartate with benzyl bromide produced a-methyl β-benzyl DL-N-benzylaspartate. Hydrogenolysis of this ester was converted to α-methyl DL-N-benzylaspartate.

음원방향 추정법의 성능평가

이채봉,홍태호 東西大學校 1997 동서논문집 Vol.3 No.1

In this paper describes the optimum beamforming algorithm when it estimates source signal localization. It is proposed many methods for the identification of a sound source localization. But in this study, This paper compares and investigates the angle resolution and sharp peak value by the simulation. The simulation perform to each of DSA(Delay Sum Arry), MV(Minimum Variance), MUSIC(MUltiple SIgnal Classification) method when signals with two or three frequency exist. In result, the MUSIC method has excellent angle resolution and sharp peak value in estimating the direction of arrival signals at each microphone for arbitrary direction of the sound source singnal.

L-N-Benzylaspartic acid의 선택적 에스테르화 반응

이채호,김일광,박승화,이영행,정봉영 圓光大學校 基礎自然科學硏究所 1987 基礎科學硏究誌 Vol.6 No.1

Selective esterification and synthesis of L-N-benzylaspartic acid from L-aspartic acid are described. L-Aspartic acid was transformed into dibenzyl L-asparate p-toluenesulfonate, which was treated with sodium bicarbonate to afford dibenazyl L-asparate. Formation of Schiff base of dibenayl ester with benzaldehyde and subsequent hydrogenation-dehydrogenation of the Schiff base produced L-N-benaylaspartic acid. L-N-Benaylaspartic adcid was transformed into L-N-benzylaspartic anhydride hydrogen bromide, which was treated with methyl alcohol and benzyl alcohol to afford a-methyl and a-benzyl L-N-benzylaspartate and L-N-benaylaspartic acid was transformed into L-N-benaylaspartic acid copper(Ⅱ) salt, which was treated with N,N,N,N-tetramethylguanidine and benzyl bromide to afford β-benzylaspartate

2-Azetidinone 유도체의 합성

이채호,조성동,이만구 圓光大學校 基礎自然科學硏究所 1987 基礎科學硏究誌 Vol.6 No.1

Synthesis of N-benzyl-2-azetidinone derivatives from αmethyl and a-benzyl N-benzylasparate is described. a-Methyl and a-benzyl N-benzylasparate were cyclized to 1-benzyl-4-methoxycarbonyl-2-azetidinone and 1-benzyl-4-benzyloxycarbonyl-2-azetidinone by employing phase transfer catalyst. The substitutents of the resulting monocyclic β-lactams were converted to hydroxymethyl, methoxymethyl and mesyloxymethyl groups.