• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.282-282
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• 1994

Radioligand결합실험에 의하여 7가지 이상의 5-hydroxytryptamine serotonin, 5-HT)수용체 subtype가 규명되어 있고, 1983년 5-HT agonist로 알려져 있던 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT)가 〔$^3$H〕5-HT수용체에 대한 결합만을 선택적으로 억제하며, 본 수용체를 직접 표식함이 알려진 이래, 본 수용체의 기능에 대한 연구가 계속되어 오고있다. 특히 항불안약으로 임상에 사용되어 왔던 benzodiazepines이 5-HT neuron의 활성을 억제한다는 사실이 보고되면서 5-HT neuron과 불안과의 관련에 관한 연구가 계속되고 있는 가운데, 새로운 항불안약으로 주목을 받고 있던 buspirone이 5-$HT_{1A}$ 수용체에 높은 친화성을 가짐이 확인되었다. 그 외에도 5-$HT_{1A}$ 수용체작용약이 항우울약, 항고혈압약으로서의 응용가능성 이 시사되면서 본 수용체작용약의 개발 및 그 기능해명이 주목을 받고 있다. 본 연구에서는, 5-$HT_{1A}$ 수용체작용약인 8-OH-DPAT와 항불안약을 개발할 목적으로 합성된 화합물인 1-[3-(3,4-methylenedioxyphenoxy)propy〕-4-phenyl piperazine (8P-554)을 이용하여, 화합물의 5-HT$_{1A}$수용체에 대한 친화성을 검토하는 방법과. 본 수용체를 통하여 나타난다고 알려져 있는 5-HT의 약리작용을 검토하는 방법을 기술하므로서, 여러가지 임상적 응용을 위하여 새롭게 합성되는 화합물의 5-$HT_{1A}$ 수용체와의 상호작용을 검색하는 방법을 제시하고자 한다.다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.11
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• pp.992-998
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• 2009

We investigated the influence of organic solvents on the droplet properties of 6,13-bis (triisopropylsilylethynyl) pentacene (TIPS-pentacene), which was used for semiconductor of organic thin film transistors (OTFTs) and deposited by ink jet printing. From the result of the investigation, the conditions of a suitable solvent is that boiling point should be above $200^{\circ}C$ to reduce coffee stain and the surface tension above 32 dyn/cm to decrease the droplet size. Consequently, we selected tetralin which have a high boiling point ($207^{\circ}C$) and high surface tension (34.3 dyn/cm) as the solvent for TIPS-pentacene, and applied it to OTFTs. In fabrication process the conventional bank process employing photolithography and etching process was replaced by ink jet printed bank process, resulting in simplifying the process. Especially, polyvinylphenol was used for the bank, and the high hydrophobicity could improve the confinement of TIPS molecules inside the bank, enhancing the performance over the conventional hydrophilic polyvinylalcohol bank. The mobility was $0.18\;cm^2/Vs$, current on/off ratio $2.09{\times}10^5$, subthreshold slope 0.42 V/dec, and off state current $0.049\;pA/{\mu}m$.

• Transactions of the Korean hydrogen and new energy society
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• v.16 no.2
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• pp.159-169
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• 2005

Cellulose, consisted of 45 wt% in wood, is usable as fuels and heavy oil additives if depolymerized to monomer unit, because the chemical structures are similar to high octane materials found in gasoline. In this study, thermochemical degradation by solvolysis reaction of cellulose such as the effect of reaction temperature, reaction time and type of solvent on conversion yield and degradation products were investigated. It was found that the effectiveness of the solvent on the sovolysis reaction was as follows; acetone>n-butanol>tetralin. When acetone was used as a solvent, the highest cellulose conversion was observed to be 91.8% at 500$^{\circ}C$, 40min. Combustion heating value of liquid products from thermochemical conversion processes was in the range of 7,330${\sim}$7,410cal/g. The energy yield and mass yield in acetone-solvolysis of cellulose was as high as 66.8% and 37.0 g oil/100g raw material after 40min of reaction at 400$^{\circ}C$. Various aliphatic and aromatic compounds were detected in the cellulose solvolysis products. The major components of the solvolysis products, that could be used as fuel, were mesityl oxide, mesitylene, isophorone.

• Journal of the Korean Wood Science and Technology
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• v.25 no.1
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• pp.1-7
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• 1997

Kraft oak lignin and ricestraw lignin from acetosolve pulping were dissolved in 50/50 mixture of tetralin/m-cresol solvent. The dissolved lignin was reacted in the pressurized autoclave which was operating at $350{\sim}500^{\circ}C$ of reaction temperature and 10~20 atms of reaction pressure respectively_Hydrogen pressure of 60~80kg/$cm^2$ was exercising into the pressurized autoclave reactor to create thermochemical hydrogenolysis reaction. It was identified by GLC, GC-MS and HPLC that the alkyl-aryl-${\beta}$-O-4 ether bond of lignin was cleaved and degraded into various smaller molecules of aromatic compound such as phenols and cresols under the reaction conditions around $300^{\circ}C$ and 10 atms of reaction temoerature and pressure. Hydrogenolysis reaction of lignin compound which was done above $500^{\circ}C$ of reaction temperature and 20 atms of reaction pressure showed that the amount of aromatic compound such as phenols and cresols degraded from reactant lignin was decreasing with newly present and increasing water out of product mixtures. It was supposed that new aliphatic compound of high molecular weight hydrocarbon is composed due to higher reaction temperature and pressure of hydrogenolysis reaction such as $500^{\circ}C$ and 20 atms, even though it was almost impossible, to identify what kind of degraded products it was by HPLC.

• Journal of the Korean Wood Science and Technology
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• v.19 no.4
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• pp.80-84
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• 1991

Lignocellulosic biomass including acetosolv ricestraw and spruce lignin were liquefied and converted into liquid hydrocarbons by catalytic hydroliquefaction reaction. These experimental works were carried out in 1-liter-capacity autoclave using 50% tetralin and m-cresol solution respectively as soluble solvent and Ni. Pd. Fe and red mud as catalyst. $H_2$ gas was supplied into the reactor for escaltion of deoxhydroenolysis reaction. Catalyst concentrations were 1 % of raw material based on weight. The ratio between raw materials and soluble solvent are 1g and 10cc. The reaction conditions are 400-$700^{\circ}C$ of reaction temperature, 10-50 atms of reaction pressure. The highest yield of hydrocarbon, so called "product oil" showed 32% and 5.5% of lowest char formation when red mud was used as catalyst. The product oil yields from those of other catalysts were in the range of 20-29%. The influence of different initial hydrogen pressures was examined in the range d 30-50 atms. A minimum pressure of 35 atms was necessary to obtain a complete recovery of souble solvent for recycling.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.170-170
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• 1998

In order to discover new types of 5-hydroxytryptamine antagonists, we have devoted our attention to investigating naturally occurring compounds having anti-5HT activity in vitro. Recently, ${\gamma}$-mangostin [1,3,6,7-tetrahydroxy-2,8-bis(3-methyl-2-bytenyl)-9H-xanthen-9-one] from the fruit hull of Garcinia mangostana Linn has been shown to be a selective antagonist for 5-hydroxytryptamine$_{2A}$ receptors in smooth muscle and platelets. It is of interesting that y-mangostin which does not have a nitrogen atom, possesses marked 5-$HT_{2A}$ receptor blocking activity. The present study was undertaken to investigate the effects of ${\gamma}$-mangostin on central 5-HT receptors by using animal behavioural models. Intracerebronventricular injection of ${\gamma}$-mangostin (10-40n mol/mouse) inhibited 5-fluoro-${\alpha}$-methyltryptamin (5-FMT) (45 mg kg$^{-1}$, i.p.)-induced head-twitch response in mice in the presence or absence of citalopram (5-HT-uptake inhibitor). Neither the 5-FMT- nor the 8-hydroxy-2-( di-n-propylamino )tetralin (5-HT$_{1A}$-agonist)-induced 5-HT syndrome (head weaving and hindlimb abduction) was affected by ${\gamma}$-mangostin. The locomotor activity stimulated by 5-FMT through the activation of at-adrenoceptors did not alter in the presence of ${\gamma}$-mangostin. 5-HT-induced inositol phosphates accumulation in mouse brain slices was abolished by ketanserin. ${\gamma}$-Mangostin caused a concentration-dependent inhibition of the inositol phosphates accumulation and the binding of [$^3H$]-spiperone, a specific 5-$HT_{2A}$ receptor antagonist, to mouse brain membranes. Kinetic analysis of the [$^H3$]-spiperone binding revealed that ${\gamma}$-mangostin increased the $_{d}$ value without affecting the $B_{max}$ value, indicating the mode of the competitive nature of the inhibition by ${\gamma}$-mangostin. These results suggest that ${\gamma}$-mangostin inhibits 5-FMT-induced head-twitch response in mice by blocking 5-$HT_{2A}$ receptors not by blocking the release of 5-HT from the central neurone. ${\gamma}$-Mangostin is a promising 5-$HT_{2A}$ receptors antagonist in the central nervous system.m.

• Archives of Pharmacal Research
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• v.27 no.10
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• pp.1065-1072
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• 2004

Depression is associated with a dysfunctional serotonin (5-hydroxytryptamine; 5-HT) system. More recently, several lines of evidence suggest that an important factor in the development of depression may be a deficit in the function and expression of $5-HT_{1A}$ receptors. The present study assessed if Nelumbinis Semen (N. s.) had an anti-depression effect through reversing a decrease in $5-HT_{1A}$receptor binding in rats with depression-like symptoms induced by chronic mild stress. Using a $5-HT_{1A}$ receptor binding assay, with a specific $5-HT_{1A}$receptor agonist, 8- OH-DPAT (8-hydroxy-2-(di-n-propylamino) tetralin), the mechanism of the anti-depression effect of N. s. on rats was investigated, and the effects compared with two well-known antidepressants, Hyperium Perforatum (St. Johns Wort) and fluoxetine (Prozac). Animals were divided into five groups: the normal (N) group without chronic mild stress (CMS), the control (C) group under CMS for 8 weeks, the Nelumbinis Semen (N. s.) treatment group under CMS for 8 weeks, the Hyperium Perforatum (H. p.) treatment group under CMS for 8 weeks and finally, the fluoxetine (F) treatment group under CMS for 8 weeks. Each treatment was administered to rats during the last 4 weeks of the 8-week CMS. A sucrose intake test was performed to test the anti-depression effect of N. s. The N. s. treatment significantly reversed the decreased sucrose intake under CMS (P<0.05 compared to control group under CMS). In the CA2 and CA3 regions of the hippocampus, both N. s. and H. p. reversed the CMS-induced decrease in $5-HT_{1A}$receptor binding. In the I to II regions of the frontal cortex, N. s. and H. p. also reversed the CMS-induced decrease in$5-HT_{1A}$receptor binding, and even showed a significant increase in $5-HT_{1A}$receptor binding compared to the F treatment group (N. s. vs. P, p<0.05, H. p. vs. P, p<0.05). However, in the hypothalamus, all treatments reversed the CMSinduced decrease in $5-HT_{1A}$receptor binding. This reversal effect of N. s. on the decrease in $5-HT_{1A}$receptor binding in the frontal cortex, hippocampus and hypothalamus of rat brains was very similar to that of H. p, but different from that of F. It is concluded that N. s. presents an anti-depression effect through enhancing $5-HT_{1A}$receptor binding.