• Archives of Pharmacal Research
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• v.9 no.1
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• pp.15-18
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• 1986

Various naturally occuring methylated amino acid derivatives were resolved on high performance liquid chromatography (HPLC), using o-phthadialdehyde as a fluorogenic reagent. We separated .$\varepsilon$-N-monomethyllysine, $\varepsilon$-N- dimethyllysine, and $\varepsilon$-N-acetyllysine from lysine derivatives. $N^{G}$-Monomethylarginine and $N^{G}$-dimethylarginine were separated from arginine derivatives. However, $\varepsilon$-N-monomethyllsine and $\varepsilon$-N-trimethyllysine, $N^{G}$, $N^{G}$-dimethylarginine and $N^{G}$, $N^{G}$-dimethylarginine were not resolved under the conditions employed. S-Methylmethionine, S-methylcysteine, and 1-N-methylhistidine or 3-N-methylhistidine were clearly separated from their reference amino acids, even though 1-N-methyl-and 3-N-methylhistidine coul not be separated.

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.38-38
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• 1999

Calculations on conformational free energies of Ac-Pro-NHMe and its $C^{\delta}$-methylated derivatives have been carried out with the higher levels of quantum-chemical methods to figure out the cis-trans isomerization of the imide bond of proline and $C^{\delta}$-methylated prolines in the gas phase and in solution.(omitted)hase and in solution.(omitted)

• Korean Journal of Pharmacognosy
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• v.27 no.1
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• pp.20-25
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• 1996

In searching for anticomplementary compounds, three phenylpropanoids were isolated from the roots of Agastache rugosa and identified as rosmarinic acid (RA), rosmarinic acid methyl ester (RAM) and caffeic acid methyl ester (CAM) by NMR analyses. RA and RAM exhibited strong inhibitory activity on both the classical pathway (CP) and the alternative pathway (AP) of the complement system, in vitro, but CAM did far less than RA and RAM. $RAM-M1{\sim}-M5$, the methylated derivatives from the RAM, showed that the inhibitory activity was decreased in inverse proportion to the number of methylated groups and $RAM-M 2{\sim}-M4$, the isomers of two methylated hydroxyl groups, exhibited different inhibition activity.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.43 no.3
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• pp.195-200
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• 2017

This study was conducted to examine the inhibitory effects of meso-dihydroguaretic acid (MDGA, 1) and its synthetic derivatives (compound 2 and 3) against NO production. MDGA is a lignan component isolated from the bark of Machilus thunbergii Sieb. et Zucc. We synthesized dimethylated MDGA (2), diacetylated MDGA (3) and compared NO inhibition of two derivatives with that of MDGA (1). MDGA (1) and compound 3 showed suppressive effects against the generation of NO in LPS-activated macrophages. RT-PCR analysis suggested that MDGA (1) and compound 3 inhibited NO production through the suppression of iNOS mRNA expression. From these results, diacetylated MDGA (3) can be used as a pro-drug for MDGA.

• Journal of Microbiology and Biotechnology
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• v.29 no.6
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• pp.839-844
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• 2019

Anthranilate derivatives have been used as flavoring and fragrant agents for a long time. Recently, these compounds are gaining attention due to new biological functions including antinociceptive and analgesic activities. Three anthranilate derivatives, N-methylanthranilate, methyl anthranilate, and methyl N-methylanthranilate were synthesized using metabolically engineered stains of Escherichia coli. NMT encoding N-methyltransferase from Ruta graveolens, AMAT encoding anthraniloyl-coenzyme A (CoA):methanol acyltransferase from Vitis labrusca, and pqsA encoding anthranilate coenzyme A ligase from Pseudomonas aeruginosa were cloned and E. coli strains harboring these genes were used to synthesize the three desired compounds. E. coli mutants (metJ, trpD, tyrR mutants), which provide more anthranilate and/or S-adenosyl methionine, were used to increase the production of the synthesized compounds. MS/MS analysis was used to determine the structure of the products. Approximately, $185.3{\mu}M$ N-methylanthranilate and $95.2{\mu}M$ methyl N-methylanthranilate were synthesized. This is the first report about the synthesis of anthranilate derivatives in E. coli.

• Archives of Pharmacal Research
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• v.13 no.4
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• pp.310-313
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• 1990

Hantzsch synthesis of 5-formyluracil (1) methyl acetoacetate (2) and methyl 3-aminocrotonate (3) gave 2, 6-dimethyl-4-(2, 4-dioxo-5-pyrimidy)-1, 4-dihydropyridine-3, 5-dicarboxylic acid dimethylester (4a) in 54.6 yield. As the same procedure, 1, 3-dimethyl-5-formyl-uracil (6) gave 2, 6-dimethyl-4-(1, 3-dimethyl-2, 4-dioxo-5-pyrimidyl)-1, 4-dihydropyridine-3, 5-dicarboxylic acid dimethyl easter (7a) IN 52.2% yield. 4a was methylated to afford 7a also in 52% yield.

• Archives of Pharmacal Research
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• v.17 no.2
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• pp.60-65
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• 1994

Reaction of c-chloro-9-benzyl-8-(methylthio)purine 3 with primary amines afforoded, the comesponding 6-(substitutedamino)purines 4a-g. The latter products when methylated with methyl iodide yielded smoothly $N^3$-methyl purinium iodide salts 5a-f rather than the probable $N^1\;and\;N^7$-derivatives. 9-Benzyl-3-methyl-6-(methylmino)-8-(methylthio)purine 8 was obtained upon treating the purinium iodide 5a with alkali. Most of the synthesized compounds were screened for their antitumor activity.

• Bulletin of the Korean Chemical Society
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• v.11 no.2
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• pp.95-99
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• 1990

The dioxygen transfer reaction from $N^5$-ethyl-4a-hydroperoxy-3-methyllumiflavin anion (4a-FlEtOO-) has been extended to isomeric aminophenol systems (1a-4a). O-aminophenol (o-AP, 1a & 2a) and p-aminophenol(p-AP, 3a & 4a) were turned out to be good substrates, whereas m-aminophenol(m-AP, 5a) was not. This is due to the charge location which is not on the carbon bearing the amino group. o-AO's react with 4a-FlEtOO- to give isophenoxazine derivatives (6 & 7) and with p-AP's to produce p-benzoquinone derivatives (8 & 9). The partition coefficients $(k_2/k_3)$ of 1a & 2a were $4.84{\times}10^{-4}\;&\;1.66{\times}10^{-5}M$, respectively and those of methylated aminophenolates, 2a & 4a were 4-10 times greater than nonmethylated substrates, 1a & 3a.

• Journal of Microbiology and Biotechnology
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• v.26 no.11
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• pp.1918-1923
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• 2016

Two baicalein derivatives, baicalin and oroxylin A, were synthesized in this study. These derivatives exhibit diverse biological activities, such as anxiolytic and anticancer activities as well as memory enhancement. In order to synthesize baicalin from aglycon baicalein using Escherichia coli, we utilized a glycosyltransferase that regioselectively transfers glucuronic acid from UDP-glucuronic acid to the 7-hydroxy group of baicalein. To increase baicalin productivity, an araA deletion E. coli mutant, which accumulates UDP-glucuronic acid, was used, and ugd, which converts UDP-glucose to UDP-glucuronic acid, was overexpressed. Using these strategies, approximately $720.3{\mu}M$ baicalin was synthesized from $1,000{\mu}M$ baicalein. Oroxylin A was then synthesized from baicalein. Two O-methyltransferases (OMTs), ROMT-15 and POMT-9, were tested to examine the production of oroxylin A from baicalein. E. coli harboring ROMT-15 and E. coli harboring POMT-9 produced reaction products that had different retention times, indicating that they are methylated at different positions; the structure of the reaction product from POMT-9 was consistent with oroxylin A, whereas that from ROMT-15 was 7-O-methyl baicalein. Using E. coli harboring POMT-9, approximately 50.3 mg/l of oroxylin A ($177{\mu}M$) was synthesized from 54 mg/l baicalein ($200{\mu}M$).

• Archives of Pharmacal Research
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• v.25 no.5
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• pp.590-599
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• 2002

Eight rigid compounds designed as esterase-stable analogues of methyl 2,5-dihydroxycinnamate (1) were synthesized. These derivatives include 2-(2',5'-dihydroxybenzylidene)cyclopentenone (3a), 2-(2',5'-dihydroxybenzylidene)cyclohexanone (3b), 2,6-bis(2',5'-dihydroxybenzy-lidene)cyclohexanone (4b), 2,6-bis(2',5'-dihydroxybenzylidene)cyclopentenone (4a), (E)-3-(2',5'-dihydroxybenzylidene)pyrrolidin-2-one (5), (E)-5-(2',5'-dihydroxybenzylidene )-1,2-isothiazolidine-1,1-dioxide (6), 4-(2',5'-dihydroxyphenyl)-5H-furan-2-one (7), and 3-(2',5'-dihydroxyphenyl)cyclopent-2-ene-1-one (8). Among the eight compounds, the furanone 7 and cyclopentenone 8 showed the most potent cytotoxicity with $IC_{50}$ values of 0.39-0.98 $\mu\textrm{g}$/mL. Compound 8 was further brominated, phenylated and methylated at the a position to give three corresponding analogues, including 2-bromo-3-(2',5'-dihydroxyphenyl)cyclopent-2-ene-1-one (24), 3-(2',5'-dihydroxyphenyl)-2-phenylcyclopent-2-ene-1-one (27), and 3-(2',5'-dihydroxyphenyl)-2-methylcyclopent-2-ene-1-one (28). Among the three, the most enhanced activity was observed with the phenylated compound 27.