• Bulletin of the Korean Chemical Society
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• 제24권11호
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• pp.1695-1698
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• 2003

• Bulletin of the Korean Chemical Society
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• 제22권11호
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• pp.1261-1263
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• 2001

• Biomolecules & Therapeutics
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• 제31권5호
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• pp.566-572
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• 2023

A chiral derivatization strategy with phenylglycine methyl ester (PGME) was employed to develop a straightforward method to determine the absolute configurations of N,N-dimethyl amino acids. The PGME derivatives were analyzed using liquid chromatography-mass spectrometry to identify the absolute configurations of various N,N-dimethyl amino acids based on their elution time and order. The established method was applied to assign the absolute configuration of the N,N-dimethyl phenylalanine in sanjoinine A (4), a cyclopeptide alkaloid isolated from Zizyphi Spinosi Semen widely used as herbal medicine for insomnia. Sanjoinine A displayed production of nitric oxide (NO) in LPS-activated RAW 264.7 cells.

• Biomolecules & Therapeutics
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• 제4권3호
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• pp.275-279
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• 1996

We have synthesized the cinnamyl derivative of minoxidil, N-2-cinnamylamino-4-amino-6-piperidinopyrimidine 3-oxide(MINAMYL). Physicochemical properties and structural analysis on this compound were examined. And also, we have screened its antialopecic effect.

• 한국식품과학회지
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• 제30권2호
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• pp.356-362
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• 1998

된장의 숙성기간을 예측하기 위하여 6개의 metal oxide sensor로 구성된 휴대용 전자코를 이용하였다. Aspergillus oryzae를 사용하여 담금한 된장은 각각 $15,\;20\;25^{\circ}C$에서 숙성시켰다. 전자코에 의한 감응도 변화량은 숙성기간에 따라 온도가 높아짐에 따라 크게 감소되었으며 센서 #3과 #4는 된장의 숙성정도와 기간간에 높은 상관관계를 보여주었다$(r^2=0.71{\sim}0.95)$. 그리고 숙성기간중 생성되는 아미노태질소와 전자코의 감응도 변화간에도 상관관계를 나타내어 휴대용 전자코로 된장의 숙성기간을 예측할 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.3957-3962
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• 2012

Iron-oxide nanoparticles (IONs) with biocompatible coatings are the only nanostructural materials which have been approved by the FDA for clinical use. Common biocompatible coatings such as hydrocarbons, polymers, and silica have profound influences on critical characteristics of IONs. Recently, amino acids were introduced as a novel biocompatible coating. In the present study, the effects of amino acids on IONs synthesis and characteristics have been evaluated. Magnetite nanoparticles with L-arginine and L-lysine coatings were synthesised by a coprecipitation reaction in aqueous solvent and their characteristics were compared with naked magnetite nanoparticles. The results showed that amino acids can be a perfect coating for IONs and would increase particle stability without any significant effects on the critical properties of nanoparticles such as particle size and magnetization saturation value.

• Asian-Australasian Journal of Animal Sciences
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• 제15권11호
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• pp.1634-1638
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• 2002

Quantification of endogenous amino acid loss at the terminal ileum is an essential means for calculation of the true amino acid digestibility of a feedstuff. Since nitrogen appeared in the determined diet or not could shift the results very much, also, none of digestibility markers could be recovered with 100% rate at the terminal ileum, the objectives of the present study were: (1) to determine endogenous amino acid losses when fed either a casein diet or a protein-free diet and (2) to examine the reliability of chromic oxide or acid insoluble ash in the protein-free diet. Six ileal-cannulated pigs ($65{\pm}1.85 kg$ BW) with a simple T-cannula in the terminal ileum were used in a replicated $3{\times}3$ Latin square designed trial, after allowed a 14 d recuperation period. Each test period ran for 12 days comprised of a 10 d adjustment period and a 2 d collection period. The endogenous AA losses of His, Ile, Lys, Cys, Thr, Val, Trp, Asp, Glu, and Ser from pigs fed the casein diet were significantly higher than those of the protein-free diet (p<0.05). No significant difference was found in the amount of endogenous amino acid loss when determined with the different markers in the protein-free diet (p>0.05). These data suggest that endogenous amino acid loss could be underestimated when a protein-free diet is used. A direct effect of dietary peptides on the endogenous amino acid loss was found when the casein diet was fed. Our results also indicate that acid insoluble ash can be used as an inert marker as an alternative to chromic oxide when measuring endogenous amino acid loss.

• 대한화학회지
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• 제37권9호
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• pp.837-844
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• 1993

N-Arylmethylideneglycine N-oxide alkyl esters(1)를 THF 용매내에서 lithium hexamethyldisilazide로 처리한 다음 할로겐화 알킬과 반응시켜 알킬화하고 이를 히드록실아민으로 분해시켜 N-hydroxy-${\alpha}$-amino acid esters(7)를 합성하였다.

• 약학회지
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• 제40권6호
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• pp.670-678
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• 1996

The combinations of N-4-salicyloamido-2-amino-6-piperidinopyrimidine 3-oxide (Salmi) and two transitional metals were colored. Among metals, Fe(III) made a distinct colored comp lex with Salmi. The mole ratio of Salmi and Fe(III) in the complex was 1:1. This Salmi-Fe(III) complex was recrystallized in Hexane/Acetone(=10/1, v/v) and investigated its physicochemical properties. The color of this complex was changed by pH.; deep violet pink in acids, orange in neutral, and yellow in bases. The range of color change was approximately 0.7 pH unit. Acid-base titration of various acidic or basic drugs using Salmi-Fe(III) complex as an indicator showed good accuracy and reproducibility.

• Bulletin of the Korean Chemical Society
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• 제13권3호
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• pp.343-344
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• 1992