• Bulletin of the Korean Chemical Society
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• v.13 no.5
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• pp.531-537
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• 1992

The approximate rates and stoichiometry of the reaction of excess potassium 2-thexyl-1,3,2-dioxaborinane hydride(KTDBNH) with 55 selected compounds containing representative functional groups under standardized conditions (tetrahydrofuran, TEX>$0^{\circ}C$, reagent : compound=4 : 1) was examined in order to define the characteristics of the reagent for selective reductions. Benzyl alcohol and phenol evolve hydrogen immediately. However, primary, secondary and tertiary alcohols evolve hydrogen slowly, and the rate of hydrogen evolution is in order of $1^{\circ}$> $2^{\circ}$> $3^{\circ}$. n-Hexylamine is inert toward the reagent, whereas the thiols examined evolve hydrogen rapidly. Aldehydes and ketones are reduced rapidly and quantitatively to give the corresponding alcohols. Cinnamaldehyde is rapidly reduced to cinnamyl alcohol, and further reduction is slow under these conditions. The reaction with p-benzoquinone dose not show a clean reduction, but anthraquinone is cleanly reduced to 9,10-dihydro-9,10-anthracenediol. Carboxylic acids liberate hydrogen immediately, further reduction is very slow. Cyclic anhydrides slowly consume 2 equiv of hydride, corresponding to reduction to the caboxylic acid and alcohol stages. Acid chlorides, esters, and lactones are rapidly and quantitatively reduced to the corresponding carbinols. Epoxides consume 1 equiv hydride slowly. Primary amides evolve 1 equiv of hydrogen readily, but further reduction is slow. Tertiary amides are also reduced slowly. Both aliphatic and aromatic nitriles consume 1 equiv of hydride rapidly, but further hydride uptake is slow. Analysis of the reaction mixture with 2,4-dinitrophenylhydrazine yields 64% of caproaldehyde and 87% of benzaldehyde, respectively. 1-Nitropropane utilizes 2 equiv of hydride, one for hydrogen evolution and the other for reduction. Other nitrogen compounds examined are also reduced slowly. Cyclohexanone oxime undergoes slow reduction to N-cyclohexylhydroxyamine. Pyridine ring is slowly attacked. Disulfides examined are reduced readily to the correponding thiols with rapid evolution of 1 equiv hydrogen. Dimethyl sulfoxide is reduced slowly to dimethyl sulfide, whereas the reduction of diphenyl sulfone is very slow. Sulfonic acids only liberate hydrogen quantitatively without any reduction. Finally, cyclohexyl tosylate is inert to this reagent. Consequently, potassium 2-thexyl-1,3,2-dioxaborinane hydride, a monoalkyldialkoxyborohydride, shows a unique reducing characteristics. The reducing power of this reagent exists somewhere between trialkylborohydrides and trialkoxyborohydride. Therefore, the reagent should find a useful application in organic synthesis, especially in the field of selective reduction.

• Horticultural Science & Technology
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• v.30 no.3
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• pp.294-300
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• 2012

Capsaicinoids are responsible for the pungency of Capsicum species. Among the several reported methods for quantifying capsaicinoids in pepper, liquid chromatography methods such as TLC and HPLC have been the most widely used due to their precision and reliability. However, they are quite expensive and time consuming to be applied to the field breeding. In this paper, we demonstrated that Gibb's reagent, 2,6-dichloroquinone chlorimide, mediated measurement of capsaicinoids is a simple and reliable method for determining the presence/absence of capsaicinoids, and estimating the amount of capsacinoids in pepper fruits. The capsaicinoids could be also detected via colorimetiric reactions of the Gibb's reagent. This simple method has been verified to be as accurate as the HPLC analysis. We have also modified this method for a high through-put analysis. This method will be useful for measuring capsaicinids in pungency breeding programs in pepper.

• Bulletin of the Korean Chemical Society
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• v.29 no.5
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• pp.1079-1082
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• 2008

• Journal of Animal Reproduction and Biotechnology
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• v.34 no.2
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• pp.111-116
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• 2019

This study was conducted to analyze the specific genes associated with sex-determination in Korean native cow. The highly organized spermatogenesis requires accurate spatial and temporal regulation of gene expression, which is governed by transcriptional, post-transcriptional, and epigenetic processes. Recently, farmers have been interested in determining the sexual identity of the calves in their farm. We analyzed the sperm of Korean native and Holstein cows, which were supplied from Hanwoo Improvement Center. We evaluated sperm motility and expression of sperm-specific genes after treating semen with both male- and female reagents. Sperm motility in Korean native cows decreased by approximately 10% in the first 30 minutes after treatment with sex-determination reagent. However, sperm motility of Holstein cows decreased to 60-70% after 15 minutes and to 20-30% after 30 minutes. We selected six specific genes expressing in the spermatozoa to analysis the gene expression level. The Real-time PCR results suggest that the selected genes (Gimap4, Tmeff1, Rac2, Abi2, Rac1, and Clu) were highly expressed in the group treated with the male reagent compared to the group treated the female reagent and to the untreated-group (control). In the present study, we suggest that the selected genes play a pivotal role in sex-determination.

• Korea Journal of Hospital Management
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• v.17 no.4
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• pp.21-31
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• 2012

This is a case study of Gangnam S University Hospital applying a par level transfer system for reagent materials. The purpose of this study is evaluated on the cutting down on inventory expenses and medical service revenue in the point of resource based view. The data was acquired through the financial statement of Gangnam S Hospital for the fiscal year 2008, 2009, 2010 and 2011, and compared with the Korea health industry statistics index for hospital accounts based on the materials in Korea Health Industry Development Institute. The results of the study are as follows. Medical reagent materials expenditure cut down as 305 million won through 2009 fiscal year. Medical profits for the Gangnam S University hospital's income statement in 2011 show well over acquired 3.37 billion won through the enlarged diagnostic test numbers. In conclusion, Gangnam S University Hospital health statistics's index shows very high profits. The results of this study have some limitations in terms of generalization as only one hospital in Seoul. Further studies with relationship inventory performance and enlarged reagent materials are expected in this area.

• YAKHAK HOEJI
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• v.30 no.6
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• pp.311-316
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• 1986

A new UV labeling reagent was developed and used in HPLC for the determination of prostaglandin $E_2$ which have weak UV light-absorbing property. This reagent, 2-bromoacetyltriphenylene, was synthesized by the bromination of 2-acetyltriphenylene which was obtained from triphenylene by Friedel-Crafts reaction. The wave length maximum (${\lambda}_{max}^{CH_3CN}$ of this reagent was 268nm. Prostaglandin E$_2$ was extracted from prostaglandin E$_2$-$\beta$-cyclodextrin using a Sep-pak $C_{18}$ cartridge. The prostaglandin E$_2$ was labeled with 2-bromoacetyl-triphenylene in aectonitrite using 18-crown-6-ether as catalyst. Derivatized prostaglandins were separated on a reversed-phase column (Radial-pak) $\mu$-Bondapak $C_{18}$ using acetonitrile: water=60:40 as mobile phase. The effluent was monitored by UV detector at 254nm filter kit. Linearity of calibration curve was obtained between 30ng and 140ng, and the lower limit of detection was 5ng.

• Journal of Sensor Science and Technology
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• v.20 no.6
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• pp.368-374
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• 2011

A microfluidic device for real-time monitoring of residual free chlorine and pH in water based on optical absorption is proposed. The device consists of a serpentine micromixer for mixing samples with a reagent, and a photodiode and light emitting diode(LED) for the detection of light absorbance at specific wavelengths, determined for specific reagent combinations. Spectral analyses of the samples mixed with N, N'-diethyl-p-phenylenediamine(DPD) reagent for chlorine determination and bromothymol blue(BTB) for pH measurement are performed, and the wavelengths providing the most useful linear changes in absorbance with chlorine concentration and pH are determined and used to select the combination of LED and photodiode wavelengths for each analyte. In tests using standard solutions, the device is shown to give highly reproducible results, demonstrating the feasibility of the device for the inexpensive and continuous monitoring of water quality parameters with very low reagent consumption.

• Toxicological Research
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• v.17 no.4
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• pp.273-277
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• 2001

Though the bamboo salt, called as "JUKYUM" has been widely used in Korea as panacea, it's toxicity were not screened completely. To investigate the toxicity of bamboo salt, we compared with the toxicity of crude salt and reagent-grade NaCl by performing single dose oral toxicity test in SD rats. Crude salt, natural sun-dried salt (crude salt) production, was purchased from the western seashore of Korean peninsular, and reagent-grade NaCl was purchased from Sigma company. Results of the single dose oral toxicity tests on bamboo salt, crude salt and reagent-grade NaCl to SD rats are as follows, $LD_{50}$ of bamboo salt was 4174mg/kg (male) and 4074mg/kg (female), that of crude salt was 4871mg/kg (male) and 4898mg/kg (female) and that of reagent-grade NaCl was 4247mg/kg (male) and 4025mg/kg (female), respectively. There were little differences in clinical signs and gross legions among groups. Finding of gross autopsy and necropsy of bamboo salt treated group were similar to other groups.er groups.

• Archives of Pharmacal Research
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• v.24 no.2
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• pp.119-125
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• 2001

We have reported that kalopanaxsaponin A (KPS-A) Isolated from Kalopanax pictus have anti-rheumatoidal activity in the rat treated with Freunds complete adjuvant (FCA) reagent. In addition, it has been also reported that KPS-A is a potent antioxidant in the rheumatoidal rat. This research was undertaken to examine whether the saponins of KPS-A and -1 could adjust the abnormal lipid metabolisms and hematological changes in immunological diseases. KPS-A significantly inhibited the increases in both triglycerides and total proteins in addition to the decrease in total cholesterol induced by FCA reagent treatment. KPS-A treatment decreased the number of leucocytes elevated by FCA reagent treatment. Excess dose of the methanol extract produced no severe toxicity on the body weight, wet organ weights and hepatic functions. Since $LD_50$ value of K. pictus methanol extract was shown to be 4,033 ${mg/kg}$, it could be estimated to be a safe agent for anti-rheumatoidal herbal medicines.

• Korean Membrane Journal
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• v.10 no.1
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• pp.13-19
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• 2008

Water softening is a very promising field for membranes and especially ultra low pressure membranes. Nanofiltration membranes based on pore-filling technology was prepared by using a new technique: the in-situ cross-linking. This route involves introducing a pre-formed polymer into the pores of a host membrane and then locking the polymer in the pores by in-situ cross-linking with an appropriate reagent. By this way, it is possible to make robust and competitive, pore-filled, anion-exchange membranes with excellent control over the properties of the incorporated gel without affecting the host membrane. In this paper, the possibilities of tuning such membranes for ultra low pressure water softening was examined by altering pore-filling chemistry (by changing cross-linking and aminating reagents). The results showed that tuning the chemistry of the pore-filling has important effects. In particularly, it had been shown that the correct selection of cross-linking reagent was not only essential to get pore-filled membranes but it could control their properties. Moreover, the aminating reagent could improve membrane performance. It was found that an increase in hydrophobicity could improve the Darcy permeability.