• Journal of the Korean Chemical Society
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• v.12 no.2
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• pp.44-46
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• 1968

The carboxymethoximes and their methyl esters of several ketosteroids were synthesized. It is suggested that the molecular weights of the ketosteroids could be determined through measuring the neutralization equivalents of their carboxymethoximes. The methyl ester of these carboxymethoximes could be utilized as useful derivatives for the identification of the ketosteriods.

• Archives of Pharmacal Research
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• v.15 no.3
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• pp.204-207
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• 1992

Glycylglycine, alanylalanine and alanylglycine were synthesized, their free carboxylic and amino groups were converted to methyl esters of N-acetylglycyglycine, N-acetylalanylglycine and N-acetylalanylalanine. The synthesized compounds were evaluated for antiepileptic activity, plasmaprotein binding, $TD_{50}$ and potentiating effect of phenobarbitone sodium.

• Archives of Pharmacal Research
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• v.13 no.3
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• pp.240-245
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• 1990

Asymmetric 2, 6-dimethyl-4-aryl-1, 4-dihydropyridine-3, 5-dicarboxylate with [N-(3, 4-methylenedioxybenzyl)-N-methyl] aminoethyl group as the ester moiety and related 1, 4-dihydropyridine derivatives were prepared and tested for the effects on vascular smooth muscles. 2-6-dimethyl-4-(3'-nitrophenyl)1-4-dihydropyridine-3, 5-dicarboxylic acid 3-[N-(3', 4-methylenedioxybenzyl-N-methyl] aminoethyl ester 5-methyl ester (11) and 2, 6-dimethyl-4-(3'-nitrophenyl)-1, 4-dihydropyridine-3, 5-icarboxylic acid 3-[N-2', 3'-methylenedioxybenzyl)-N-methyl] aminoethyl ester 5-ethyl ester (150 showed potent vasodilating activities $IC_{50}$($10_{-8}M$) was 2, 6 and 2.7 for 11 and 15, compared with 3.5 for nicardipine.

• Journal of Electrical Engineering and Technology
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• v.12 no.2
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• pp.820-829
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• 2017

Vegetable oil dielectrics have been used in transformers as green alternatives to mineral insulating oils for about twenty years, because of their advantages of non-toxic, biodegradability, and renewability. However, the viscosity of vegetable oils is more than 3 times of mineral oils, which means a poor heat dissipation capacity. To get low-viscosity dielectrics, transesterification and purification were performed to prepare vegetable oil methyl esters in this study. Electrical and physical properties were determined to investigate their potential as dielectrics. The results showed that the methyl ester products had good dielectric strengths, high water saturation and enough fire resistance. The viscosities (at $40^{\circ}C$) were 0.2 times less than FR3 fluid, and 0.7 times less than mineral oil, which indicated superior cooling capacity as we expected. With the assistance of 0.5 wt% pour point depressants, canola oil methyl ester exhibited the lowest pour point ($-26^{\circ}C$) among the products which was lower than FR3 fluid ($-21^{\circ}C$) and 25# mineral oil ($-23^{\circ}C$). Thus, canola oil methyl ester was the best candidate as a low-viscosity vegetable oil-based dielectric. The low-viscosity fluid could extend the service life of transformers by its better cooling capacity compared with nature ester dielectrics.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.135-137
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• 1999

For the synthesis of new anti-inflammatory agents as indol derivatives, we have synthesized ${\alpha}$-benzoyl-1-ethyl-1,3,4,9-tetrahydro-8-ethyl-9-(N-benzoyl)pyrano[3,4-b]indole-1-acetic acid methyl ester. It was a new method for ${\alpha}$-substituted etodolac carboxylic acid. The synthetic process was composed of four steps, and 7-ethylindole and oxalyl chloride were used as starting materials. The third step, cyclization was carried out by addition of borontrifluoride diethyl etherate in 66% yield. The step of reduction and cyclization were simplified successfully. The final product, ${\alpha}$-benzoyl-1-ethyl-1,3,4,9-tetrahydro-8-ethyl-9-(N-benzoyl)pyrano[3,4-b]indole-1-acetic acid methyl ester was obtained in 66% yield by the reaction of methyl 1,8-dimethyl-1,3,4,9-tetrahydropyrano[3,4-b]indole-1-acetate (etodollic acid methyl ester) and benzoyl chloride.

• Journal of the Korean Graphic Arts Communication Society
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• v.29 no.1
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• pp.45-59
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• 2011

According as gradually increasing the demand for Eco-friendly products it has been progressed fairly development at a field of printing and printing inks. The Inks are used by soy oil beginning of ink industry for preventing environment. Now it is possible to make Eco-friendly inks with vegetable ester. So it is not necessary to use petroleum-based solvents for preventing environment. But There is some problems if using vegetable ester to inks. Vegetable ester has high solubility, it causes misting and low viscosity of the Inks. So resin is required high performance. Thus, in this paper, I studied about the properties variation of the Varnish and inks According to using the phenolic modified rosin ester and Soy oil Methyl esters. The compared in order of average molecular weight by the GPC method, rheological properties were found by rotational rheometer, and emulsion behavior were compared by high speed emulsification tester.

• Applied Biological Chemistry
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• v.45 no.4
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• pp.207-211
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• 2002

This study was conducted to increase the shelf life of grape by edible coating material such as methyl cellulose (MC) with antimicrobial substances, n-capric acid isopropyl ester (ci) and sodium nitrate (sn), added by spraying method. The quality changes of packaged grapes with wrapping PE film on EPS tray were investigated for 16 days at $30{\circ}C$. The shelf-lives of C and MCci based on the weight reduction ratio of 7% were 6 days and 9 days, respectively. The reduction rate of acidity of C was higher value than those of treatments during 18 days of storage at $30{\circ}C$. The vitamin C reduction ratios of C, MCsn and MCci were 64.8, 51.5 and 49.8%, respectively, after 16 days at $30{\circ}C$. The reduction rates of firmness of C, MCsn and MCci after 16 days at $30{\circ}C$ were 44.2, 26.5, and 23,2%, respectively compared to that of initial storage grapes. The additions of ci and sn had much affected the reductions of bacteria and yeast counts especially early stage of storage. The hedonic sensory evaluation scores of MCci and MCsn had higher values than those of MC.

• Korean Journal of Pharmacognosy
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• v.26 no.2
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• pp.130-138
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• 1995

Phytochemical study on the aerial parts of Solanum lyratum (Solanaceae) was carried out. On the basis of phytochemical and spectroscopic evidences, compound I was identified as mixtures of hexadecanoic acid methyl ester, 2,6,10,15-tetramethyl heptadecane, tricosane, tetracosane, pentacosane, docosanoic acid methyl ester, docosane, tricosanoic acid methyl ester, 8-hexyl pentadecane, tetracosanoic acid methyl ester, pentatriacontane, hexatriacontane, eicosane, hexacosane, hentriacontane and stigmasta-5,23-dien $3-{\beta}-ol$, and compound II, III, IV and V were identified as hexacosanoic acid methyl ester, ${\beta}-sitosterol-{\beta}-{_D}-glucoside$, $3-O-{\alpha}-{_L}-rhamnopyranosyl-(1->2)-{\beta}-{_D}-glucuronopyranosyl$ diosgenin and $3-O-{\alpha}-{_L}-rhamnopyranosyl-(1->6)-{\beta}-{_D}-glucopyranosyl$ quercetin (rutin), respectively. Rutin was identified as one of the active principles having antioxidative effect from S. lyratum.

• Journal of the Korean Chemical Society
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• v.19 no.5
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• pp.367-374
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• 1975

Glycine residue in N-X-glycylphenylalanine methyl ester(X = trifluoroacetyl or acetyl) was converted into aspartic acid derivative by a photoalkylation reaction. The reaction was induced with 350 nm lamp using a combination of diacetyl/di-t-butyl peroxide (DBP) as the photoinitiator, and acetic anhydride as the alkylating agent. In the thermal reaction with DBP and acetic anhydride, the same alkylation reaction of the dipeptide was observed. From this thermal alkylation reaction the photoalkylation reaction is also thought to undergo via free radical mechanism.

• Environmental Engineering Research
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• v.15 no.3
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• pp.129-134
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• 2010

The optimization of experimental parameters, such as catalyst type, catalyst concentration, molar ratio of alcohol to oil and reaction temperature, on the transesterification for the production of rapeseed methyl ester has been studied. The Taguchi approach (Taguchi method) was adopted as the experimental design methodology, which was adequate for understanding the effects of the control parameters and to optimize the experimental conditions from a limited number of experiments. The optimal experimental conditions obtained from this study were potassium hydroxide as the catalyst, at a concentration of 1.5 wt %, and a reaction temperature of $60^{\circ}C$. According to Taguchi method, the catalyst concentration played the most important role in the yield of rapeseed methyl ester. Finally, the yield of rapeseed methyl ester was improved to 96.7% with the by optimal conditions of the control parameters which were obtained by Taguchi method.