Jin Hyun Jeong

Bis-(3-hydroxyphenyl) diselenide inhibits LPS-stimulated iNOS and COX-2 expression in RAW 264.7 macrophage cells through the NF-κB inactivation

OBJECTIVES Previously, we reported that diaryl diselenide compounds have strong inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in macrophages. In this study, we investigated the molecular mechanisms underlying NO suppression and prostaglandin E(2) (PGE(2)) production by diaryl diselenide compounds, bis-(2-hydroxyphenyl) diselenide (DSE-A), bis-(3-hydroxyphenyl) diselenide (DSE-B), bis-(4-hydroxyphenyl) diselenide (DSE-C), dipyridyl diselenide (DSE-D) and diphenyl diselenide (DSE-E). METHODS The effect of these compounds on NO suppression and PGE(2) production was investigated in RAW 264.7 macrophages. KEY FINDINGS Our data indicate that of the above, DSE-B most potently inhibits NO and PGE(2) production, and that it also significantly reduces the releases of tumour necrosis factor (TNF)-alpha, interleukin(IL)-1beta and IL-6. Consistent with these observations, DSE-B also reduced the protein levels of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2), and the mRNA levels of iNOS, COX-2, TNF-alpha, IL-1beta and IL-6. Furthermore, DSE-B inhibited LPS-induced nuclear factor-kappaB (NF-kappaB) activation, which was associated with the prevention of the inhibitor kappaB-alpha (IkappaB-alpha) degradation and a subsequent reduction in nuclear p65 protein levels. CONCLUSIONS Taken together, our data suggest that the anti-inflammatory properties of DSE-B are due to reduction in the expression of iNOS, COX-2, TNF-alpha, IL-1beta and IL-6 through the down-regulation of NF-kappaB binding activity.

Stereoselective synthesis of (+)-spectaline

Abstract Our synthesis of (+)-spectaline revealed that the methodology involving diastereoselective palladium(0)-catalyzed oxazoline formation and intramolecular reductive amination by catalytic hydrogenation of an oxazoline is an effective method for the asymmetric synthesis of natural products possessing complex functionalized piperidine cores.

Lupane-glycoside ofAcanthopanax trifoliatus formatristigmatis leaves

This report contains the first characterization of acanthodiolglycoside which belongs to pentacyclic lupane triterpene glycoside

Synthesis of new diselenide compounds as anti-inflammatory agents

Many diselenide compounds are used as antioxidants, enzyme inhibitors and cytokine inducers. Three new diselenide compounds, bis-(2-hydroxyphenyl) diselenide, bis-(3-hydroxyphe-nyl) diselenide and bis-(4-hydroxyphenyl) diselenide were designed and synthesized as antiinflammatory agent. All of them were found to have strongin vitro activity in anti-inflammatory assays.

A convenient synthesis of an anti-helicobacter pylori agent, dehydrodiconiferyl alcohol

Potential anti-Helicobacter pylori agent dehydrodiconiferyl alcohol was synthesized in 44% overall yield, starting from vanillin which could be commercially available. Carbon extension of vanillin followed by the Horner-Wadsworth-Emmons reaction, a biomolecular radical coupling reaction and DIBAL-H reduction gave dehydrodiconiferyl alcohol.

Gadolinium-chlorin is potentially a new tumor specific MRI contrast agent

In this study, a newly-synthesized metalloporphyrin, Gd-chlorin (PB Chlorin), was investigated by using a simple tissue phantom to test its efficacy as an MRI contrast, agent. This study demonstrated the potential activity of Gd-chlorin as not only a MRI contrast agent, but also as a PDT photosensitizer by using a simple tissue phantom and conducting a very brief MRI experiment.

A convergent synthetic study of biologically active benzofuran derivatives

In order to construct a benzofuran library, we developed a model study of benzbromarone. Synthesis has been achieved in 53% overall yield, starting from phenolvia the key intermediate 2-ethylbenzofuran which was afforded by intramolecular Wittig reaction.

Stereoselective synthesis of (±)-epibatidine analog: (±)-2β-(2-chloro-5-pyridinyl)-8-azabicyclo[3.2.1]octane

Stereoselective synthesis of (±)-epibatidine analog2, which contains the 8-azabicyclo[3.2.1]octane ring system, was achieved by using palladium-catalyzed Heck-type coupling reaction from3.

An efficient synthesis of risperidone via stille reaction : Antipsychotic, 5-HT2, and dopamine-D2-antagonist

Risperidone has been reported to have neuroleptic activity. In this study, risperidone was synthesized using a new method involving a stille reaction, in which 2-methyl-3-vinyl-6,7,8,9-tetrahydropyrido [1,2-a]pyrimidin-4-one was synthesized (5). The chemical synthesis process was found to be simple and produced risperidone in a high yield. In addition, can be easily scaled up for large scale synthesis.

Development of new dihydropyran linker for solid-phase reaction

The linker which plays a role in connecting a polymer with a scaffold has become an important part in solid-phase reaction. To develop a new linker for alcohols and carbohydrates, dihydropyran moiety was selected in this study.New linker, 1-(4′,5′-dihydro-5H-pyranyl)-7-hydroxyheptan-3-one (5) was synthesizedvia four steps from δ-valerolactone. This can be called as DDHP-linked Wang resin due to double dihy-dropyran rings. To the one pyran ring of new linker5 was added Wang resin and other alcohols and carbohydrates as scaffolds were then added successfully to the another pyran ring. Carbohydrate and hydroxyl resins were connectedvia new linker in a 70% loading yield. The detachment of glucose moiety in the presence of PPTS (2 equiv.) in 1∶1n-butanol/1,2-dichloroethane at 60°C for 12 h was carried out quantitatively. When certain combinatorial chemical works are carried out using this dihydropyran linker, Wang resin itself can be recovered. Its fact is particularly very important in industry, because recovered resins can be recycled.