• Proceedings of the PSK Conference
• /
• 2000.04a
• /
• pp.156.1-156.1
• /
• 2000

• Proceedings of the Membrane Society of Korea Conference
• /
• 2003.05a
• /
• pp.41-44
• /
• 2003

• Journal of the Korean Chemical Society
• /
• v.47 no.5
• /
• pp.530-532
• /
• 2003

• Archives of Pharmacal Research
• /
• v.28 no.11
• /
• pp.1219-1223
• /
• 2005

6-[2-(Benzoxazol-2-ylmethylamino)ethoxy]-1-alkyl-1H-indole-2-carboxylic acids were designed and synthesized as $\beta$-amyloid (A$\beta$) fibril assembly inhibitors. Their inhibitory activity on A$\beta$, aggregation was evaluated by thioflavin T assay although their activities were insignificant.

• Journal of the Korean Chemical Society
• /
• v.41 no.4
• /
• pp.214-218
• /
• 1997

• Bulletin of the Korean Chemical Society
• /
• v.11 no.5
• /
• pp.376-379
• /
• 1990

To find out a correlation between antibacterial activity and physical properties of 7-substituted 1-ethyl-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid, dipole moments, charge distributions, and hydrophobicities were calculated. The atomic charges and the dipole moments to not give any correlations with inhibition of DNA gyrase, but the calculated hydration free energies show some correlations.

• Bulletin of the Korean Chemical Society
• /
• v.15 no.6
• /
• pp.448-452
• /
• 1994

2-Hydroxymethyl-2,5-dihydrothiophene 1,1-dioxide (1) was prepared from thiophene-2-carboxylic acid by consecutive reactions involving the Birch reduction, esterification, reduction with lithium aluminum hydride, and oxidation with Oxone$^{\circledR}$. The esterification of alcohol 1 with various unsaturated carboxylic acids provided the precursors 8 for the intramolecular Diels-Alder reaction. The cheletropic expulsion of sulfur dioxide from the esters 8 followed by intramolecular Diels-Alder reaction furnished bicyclic ${\gamma}$-and ${\delta}$-lactones.

• Bulletin of the Korean Chemical Society
• /
• v.11 no.6
• /
• pp.538-542
• /
• 1990

New aminothiazolyl cephalosporins with alkoxyiminomethyl(2-aminothiazol-4-yl)acetyl substituents at 7-position of cephems were synthesized starting from (2-aminothiazol-4-yl)acetate via one carbon homologation followed by acylation with 7-aminoceph-3-em-4-carboxylic acid derivatives. These new aminothiazolyl cephalosporins exhibit promising in vitro activities against various strains including Gram positive bacteria.

• Bulletin of the Korean Chemical Society
• /
• v.8 no.4
• /
• pp.264-269
• /
• 1987

Various carbocation-mediated cyclizations to tricyclene structure (basically, tricyclo $[2,2,1,0^{2,6}]$ heptane skeleton) were carried out, starting from protonated species of either 3-methyl-2,5-norbornadiene-2-carboxylic acid (10) or 3-methylene-5-norbornene-2-carboxylic acids (18 and 19). The resulting products were individually converted to ${\pi}$-iodotricyclene (35), a pivotal intermediate in almost all syntheses of tricyclene terpenes.

• Korean Journal of Food Science and Technology
• /
• v.40 no.6
• /
• pp.707-711
• /
• 2008

The principal objective of the current study was to isolate a purpurogallin derivative as an oxidation product from gallic acid, in an effort to assess the anti-inflammatory effects of this compound. Purpurogallin derivative is known to be the one of the oxidation products of gallic acid. This compound has been identified as a minor chemical component in fermented tea products. It has been previously demonstrated that theaflavins, the oxidation products of catechins found in fermented tea products, exert profound antioxidant and anti-inflammatory effects. However, the biological activities of a minor chemical component in fermented teas have yet to be evaluated. Purpurogallin carboxylic acid (PCA) was identified as a major oxidation product of gallic acid from a peroxidase/hydrogen peroxide oxidation model system. The identity of the PCA was verified by $^{1}H$ NMR, $^{13}C$ NMR and MS techniques. PCA treatment significantly suppressed the generation of pro-inflammatory mediators including nitric oxide and IL-6 in lipopolysaccharide (LPS)-stimulated RAW264.7 murine macrophages. According to the nitrite assay, PCA 100, 75, and $50{\mu}g/mL$ treatment dose-dependently inhibited NO production by 57.6, 41.5, and 21.8%, respectively, in LPS-stimulated RAW264.7 murine macrophage cells. Moreover, IL-6 production was inhibited to a significant degree with PCA treatment of 100 and $75{\mu}g/mL$ at 43.1 and 23.9%, respectively. PCA treatment also significantly suppressed $PGE_2$ production at levels of 100 and $75{\mu}g/mL$. These results showed that PCA exerts inhibitory effects on the production of inflammatory mediators.