• 공업화학
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• 제10권1호
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• pp.135-137
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• 1999

새로운 인돌 유도체인 항염증제를 합성하기 위하여 ${\alpha}$-benzoyl-1-ethyl-1,3,4,9-tetrahydro-8-ethyl-9-(N-benzoyl)pyrano[3,4-b]indole-1-acetic acid methyl ester(10)을 합성하였다. 출발물질은 7-ethylindole과 oxalyl chloride로 하여 4단계로 이루어졌다. 셋째 단계는 borontrifluoride diethyl etherate을 사용하여 66%로 고리화반응을 하였으며, 환원반응과 고리화반응도 효율적으로 단순화하였다. 최종생성물인 ${\alpha}$-benzoyl-1-ethyl-1,3,4,9-tetrahydro-8-ethyl-9-(N-benzoyl)pyrano[3,4-b]indole-1-acetic acid methyl ester는 4단계에서 얻은 methyl 1,8-dimethyl-1,3,4,9-tetrahydropyrano[3,4-b]indole-1-acetate(etodollic acid methyl ester)를 benzoyl chloride와 반응하여 66%의 수율로 얻었다.

• 한국식품과학회지
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• 제5권4호
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• pp.249-257
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• 1973

1. myo-inositol에서 산화(酸化), 환원반응(還元反應)을 거쳐서 scyllo-[XVI], epi-inositol[XXI], ax.-과 eq.-alcohol[III],[IV],[XXIII],[XXIV]등(等)에 도달(到達)시켰고, muco-inositol[XXIX]을 합성(合成)하였다. 2. inositol stereomer의 5-nitrofuroic acid ester인 8종(種) 신화합물(新化合物)을 합성(合成)하였다. 즉 hexakis-O-(5-nitro-2-furoyl)-myo-inositol [IX], hexakis-O-(5-nitro-2-furoyl)-scyllo-inositol [XXI], hexakis-O-(5-nitro-2-furoyl)-epi-inositol [XXVII], hexakis-O-(5-nitro-2-furoyl)-muco-inositol [XXXII], 2-O-(5-nitro-2-furoyl)-myo-inositol [VII], 4-O-(5-nitro-2-furoyl)-myo-inositol [VIII], O-(5-nitro-2-furoyl)-scyllo-inositol [XX], 그리고 2-O-(5-nitro-2-furoyl)-epi-inositol [XXVI] 등(等)이다. 3. 이 8종(種) ester는 모두 항균력(抗菌力)이 있고, scyllo-, myo-, epi-, muco-inositol ester 의 순(順)으로 증대(增大)되는 경향(傾向)이 있으며 항균력(抗菌力)은 ester의 입체구조(立體構造)와 관련(關聯)되는 것이라 생각된다.

• 대한화학회지
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• 제19권3호
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• pp.169-173
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• 1975

Aminobenzylphosphonic acid를 포함하고 있는 dipeptide들의 합성을 carbodimide법으로 시도하여 다음과 같은 새로운 화합물들을 얻었다. Glycyl-dl-1-aminobenzylphosphonic acid, alanyl-dl-1-aminobenzylphosphonic acid, L-alanyl-dl-1-aminobenzylphosphonic acid, N-phthalyl-L-phenylalanyl-dl-1-aminobenzylphosphonic acid diethyl ester, N-carbobenzoxyglycyl-dl-1-aminobenzylphosphonic acid diethyl ester, N-carbobenzoxy-alanyl-dl-1-aminobenzylphosphonic acid diethyl ester, N-carbobenzoxy-L-alanyl-dl-1-aminobenzylphosphonic acid diethyl ester, glycyl-dl-1-aminobenzylphosphonic acid diethyl ester hydobromide, alanyl-dl-1-aminobenzylphosphonic acid diethyl ester hydrobromide 및 L-alanyl-dl-1-aminobenzylphosphonic aciddiethyl ester hydrobromide.

• Journal of Microbiology and Biotechnology
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• 제11권6호
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• pp.951-956
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• 2001

A 28-kDa extracellular lipase (pI 8.7) was purified to homogeneity from the culture supernatant of Trichosporon sp. Y- 11 by mmonium sulfate precipitation, DEAE-Sephadex A-50, Bio-Gel P-30, CM- Sephadex C-50, and Bio-Gel P- 10 chromatographies. The purified enzyme exhibited a specific activity of $2,741{\;}{\mu}mol/min/mg$ based on the hydrolysis of triolein, and the optimal hydrolysis activity was dentified at pH 8.0 and $40^{\circ}C$. The enzyme activity was inhibited by $Ag^+$ and enhanced by $Fe^{2+}$, $Fe^{3+}$, $Mg^{2+}$, $Mn^{2+}$, and $Li^{+}$. The enzyme activity exhibited for the hydrolysis of both tributyrin and trilinolein. The ester synthesis of unsaturated fatty acids with various alcohols catalyzed by the purified lipase in a nonaqueous medium or microaqueous system was also investigated. The esterification activity of the lipase increased with an increase of the carbon chain length in the alcohol. The synthesis rate of linoleic acid and oleyl alcohol was the highest with an optimal temperature and pH of $40^{\circ}C$ and 8.0, respectively. The water content and agitation also affected the esterification activity of the lipase.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.597-600
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• 2000

In this study the enzymatic synthesis of ester-linked conjugates of amino acid and monosaccharide in pyridine was tested by the catalysis of Optimase M-440, an alkaline serine pretense. Optimase M-440 showed the higher activity in the reaction of monosaccharides which have one or more primary -OH groups. And also Optimase M-440 showed high regioselectivity; The transesterification of primary -OH group selectively occurred.

• Journal of Pharmaceutical Investigation
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• 제23권2호
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• pp.61-69
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• 1993

Prodrug of cefazolin (CFZ) was prepared with the objective of improving its oral bioavailability. Cefazolin phthalidyl ester (CFZ-PT) was synthesized and evaluated as potential prodrug form. The successful synthesis of CFZ-PT was identified by spectroscopic analysis. Partition coefficient studies showed that CFZ-PT is more lipophilic than CFZ and the ester was hydrolyzed enzymatically into the parent drug in blood, liver and intestinal homogenates. The pharmacokinetic characteristics of CFZ-PT and CFZ were compared following oral administrations to rabbits. Serum CFZ concentration was determined by HPLC method and the ester compound (prodrug) was not detected in serum following oral administration of CFZ-PT. CFZ-PT did not have antimicrobial activity in vitro against Bacillus subtilis ATCC 6633, whereas CFZ-PT in serum after oral administration to rabbits had antimicrobial activity. From above observations, it was noted that CFZ-PT is rapidly hydrolyzed to CFZ in the body and the bioavailability of CFZ-PT was increased by 3.5-fold than that of CFZ. From these results of this study, it was concluded that CFZ-PT may be a novel prodrug of CFZ which can improve the oral absorption of CFZ.

• 한국식품영양학회지
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• 제36권5호
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• pp.354-359
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• 2023

A mono-type glycerine fatty acid ester compound was chemically synthesized using medium-chain fatty acids with antibacterial activity, and the physicochemical quality and antibacterial activity of the synthesized glycerine medium-chain fatty acid ester compound were measured. At a reaction molar ratio of MCT(medium chain triglyceride) to glycerine of 1:2.5, 48.15% mono ester was produced. The physicochemical analysis of the synthesized glycerine fatty acid ester compound showed an acid content of 0.38~0.60%, which tended to increase slightly as the glycerine molar ratio increased. The saponification value decreased as the synthesized molar ratio of glycerine increased from 218 to 284. The number of bacteria was measured to confirm the degree of antibacterial activity of glycerine medium-chain fatty acid esters against food poisoning bacteria, Bacillus cereus and Salmonella typhi. The number of bacteria significantly decreased as the MCT:glycerine molar ratio increased. In particular, the antibacterial effect between the treatment groups was the highest when at an MCT:glycerine molar ratio of 1:2.5.

• Journal of Microbiology and Biotechnology
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• 제11권4호
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• pp.649-655
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• 2001

The kinetics of the thermolysin-catalyzed synthesis of N-(benzyloxycarbonyl)-L-phenylalanyl-L-leucine ethyl ester (Z-Phe-LeuOEt) from N-(benzyloxycarbonyl)-L-phyenylalanine (Z-Phe) and L-leucine ethyl ester (LeuOEt) in an ethyl acetate saturated aqueous system in a batch operation were studied. The kinetics for the synthesis of Z-Phe-LeuOEt were expressed using a rate equation for the rapid equilibrium random bireactant mechanism. The four kinetic constants involved in the rate equation were determined numerically by the quasi-Newton method so as to fit the calculated results with the experimental data. Within the pH and temperature range examined, the $K_{cat}$ value for the synthesis of Z-Phe-LeuOEt reached a maximum at pH 7.0 and $45^{\circ}C$, whereas the affinity between Z-Phe and thermolysin reached a maximum at pH 6.0 adn $40^{\circ}C$. The inhibitory effect of Z-Phe on the condensation reaction decreased as the pH and temperature decreased. In contrast, they affinity between LeuOEt and thermolysin remained unchanged within the pH and temperature range examined. Therefore, it was concluded that the protonation state of the carboxyl groups. of Z-Phe was more imprtant than that of the amono groups of LeuOEt for the synthesis of Z-Phe-LeuOEt in the present solvent system. The equilibrium yield at pH 6.0 and $30^{\circ}C$ was 8% higher than that at pH 7.0 and $40^{\circ}C$, although the rate was much slower. This result suggested that the affinity between the enzyme and the substrate rather than the overall rate was a more important factor affecting the equilibrium yield, when the peptide synthesis was carried out in a product-precipitation system.

• Bulletin of the Korean Chemical Society
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• 제12권1호
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• pp.71-74
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• 1991

Facile methods are reported for the synthesis of optically pure derivatives of (2S,3R)-3-amino-2-hydroxy-4-(4'-hydroxyphenyl)b utanoic acid. To avoid troublesome synthesis of O-benzyl-N-Boc-D-tyrosine, without the protection of phenolic OH group of tyrosine N-Boc-D-tyrosine methyl ester was reduced with DiBAL to the aldehyde. The aldehyde was converted via the cyanohydrin to (2S,3R)-3-amino-2-hydroxy-4-(4'-hydroxyphenyl)butanoic acid (AHpHBA). The mixture of diastereomers was converted to the corresponding Boc-AHpHBA methyl ester derivatives and separated by chromatography over silica gel. Optically active (2S,3R)-AHpHBA was used to synthesize aminopeptidase inhibitors.

• Bulletin of the Korean Chemical Society
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• 제12권4호
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• pp.376-379
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• 1991

Pyrazolone group containing resin was tested as an acyl carrier in solid phase peptide synthesis. Several kinds of dipeptide derivatives were prepared by aminolysis reactions of Boc-amino acid-pyrazolone resin active ester with various carboxyl protected amino acid derivatives. It was found that the rates of aminolysis reactions were largely dependent on the bulkiness of the amino acid side chains, the carboxyl protecting groups, and the swelling property of the resin. All the dipeptide derivatives were obtained in high yield in 20-30 minutes, and the pyrazolone resin could be reused repeatedly in peptide synthesis without any change of its reactivity.