• Applied Chemistry for Engineering
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• v.1 no.2
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• pp.249-255
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• 1990

The conditions for separation and identification of anionic and nonionic surfactants by thin layer chromatography were investigated. Polyoxy alkylene-type nonionic surfactants were identified by the distribution of alkyl chain and alkylene oxide. Various polyoxyethylenated nonyl phenols were easily distinguished by densitometer. Some anionic surfactants were identified by $R_f$ and color, and the mixtures of anionic and nonionic surfactants were separated. Polyoxyethylenated fatty acid was separated into three parts of diester, monoester and polyethylene glycol, respectively, and the mixed ratio was determined by densitomer. All the experiments were carried out in 13-20 minutes, and the length of run was 80mm.

• Applied Chemistry for Engineering
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• v.24 no.1
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• pp.72-76
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• 2013

In this study, the boric acid which is a by-product in the esterification process to obtain norbornene diester derivatives was recovered, and then its reusability for esterification of norbornene was investigated. Four types of trialkyl borate (tributyl borate, tripentyl borate, and triisopentyl borate, trihexyl borate) were synthesized through the esterification with boric acid and four types of alcohol. Then, diester derivatives were synthesized by esterification with the synthesized trialkyl borate and norbornene dicarboxylic acid. The conversion of norbornene dicarboxylic acid is 89.50~99.31%. The boric acid which is a by-product in the esterification were recovered with NaCl salt and used for synthesizing trialkyl borate. The recovery rate was 92.43~99.35 %. When the recovered trialkyl borate was used in esterification, there are little losses of the yield. Since boric acid which is a major by-product is able to be recovered, the process is expected to be a clean technology to prevent an environmental pollution by the emission of chemical compounds.

• Journal of the Korean Applied Science and Technology
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• v.18 no.4
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• pp.306-315
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• 2001

Our study is aimed at proposal of systematic verification method of molecular structure using measuring method of selective ionic determination and spectrometry on 34 kinds of surfactants such as sodium dodecyl sulfate(SDS) which are most widely used today. In the IR spectrum, unsaturated fatty acids reveal themselves by HC= at $3000{\sim}3020cm^{-1}$, and intensity of $720cm^{-1}$ depends on carbon length of alkyl group. Also ethylene oxide(EO) adducts exhibit weak characteristic bands by $-CH_{2}-CH_{2}-O$ at 1350, 1100 and $950cm^{-1}$. Isethionate can be distinguished from diester succinate by intensity ratio of 1740 and $1200cm^{-1}$ spectrums, the ratio of latter is close to 1 due to 2 carboxylate radical in diester succinate. Quaternary ammonium salts exhibit characteristic band of $C_{4}N^{+}$ at $1000-900㎝^{-1}$. In the case of dialkyl dimethyl ammonium salts in quaternary ammonium surfactants, the spectrum of $3000cm^{-1}$ by $N-CH_{3}$ collapses to a very weak band at $3020cm^{-1}$. In ammonium heterocyclic derivatives, pyridinium salts show characteristic bands at 1640 and $1460cm^{-1}$, while imidazolinium salts exhibit characteristic band at $1620-1610cm^{-1}$. In the characteristic spectrum at $1080-1050cm^{-1}$ on OH radicals of the alkyl esters, primary alcohol appears as weak band and the 2 bands show in almost same intensity when primary and secondary alcohols exist together in one molecule. Also, alkyl ester of polyhydric alcohols appears as various broad band.

• Journal of Korean Neurosurgical Society
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• v.64 no.6
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• pp.864-872
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• 2021

Objective : The aim of our study is to investigate the cytotoxic, antioxidant, and antimicrobial effects of newly synthesized boron compounds in U87MG glioblastoma cell treatment. Methods : We synthesized boron glycine monoester (BGM) and boron glycine diester (BGD) structures containing boron atoms and determined their cytotoxic activities on glioblastoma by the MTT method. The inhibitory concentration 50 (IC₅₀) value was calculated with GraphPad Prism 5.0 program. The IC₅₀ values were administered 48 hours on U87MG glioblastoma cell. Catalase (CAT), acid phosphatase (ACP) and alkaline phosphatase (ALP) enzyme activity, malondialdehyde (MDA), total glutathione (GSH), and total protein levels were detected using spectrophotometric methods. We determined the antimicrobial activities of BGM and BGD with the disc diffusion method. Results : After 48 hours of BGM and BGD application to U87MG glioblastoma cells, we found the IC₅₀ value as 6.6 mM and 26 mM, respectively. CAT and ACP enzyme activities were decreased in BGM and BGD groups. MDA which is a metabolite of lipid peroxidation was increased in both boron compounds groups. GSH level was reduced especially in BGD group. BGM and BGD have been found to be antimicrobial effects. Conclusion : Boron compounds, especially the BGM, can provide a new therapeutic approach for the treatment of glioblastoma with their anticancer, antioxidant, and antimicrobial effects.

• Journal of Life Science
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• v.34 no.2
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• pp.138-144
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• 2024

Crocin is a major carotenoid of the Gardenia jasminoides fruit and Crocus sativus stigma (saffron), which are used in various cuisines as flavoring and coloring agents, as well as in phytomedicine for the treatment of several disorders, including headache, fever, edema, fatty liver, viral hepatitis, respiratory disease, menstruation disorders, insomnia, and hypertension. Crocin (C₄₄H₆₄O₂₄) is a chemical diester composed of the dicarboxylic acid crocetin and disaccharide gentiobiose. Many in vitro and in vivo studies have been conducted about the biological and pharmacological function and toxicity of crocin. Crocin has been revealed to have no genotoxicity and pathological manifestation. Crocin acts as an antioxidant, anti-cancer, memory enhancer, anxiolytic, antidepressant, aphrodisiac, anti-atherosclerotic, cardioprotector, and hepatoprotector. Here, an inclusive review of crocin is introduced based on previously explored studies referred to in the literature. Different studies have confirmed the protective role of crocin in the pathogenesis of inflammatory diseases, including inflammatory bowel diseases, gastritis, asthma, atherosclerosis, rheumatoid arthritis, multiple sclerosis, type 1 diabetes, Alzheimer's disease, Parkinson's disease, and depression. It is surmised that crocin suppresses inflammatory, antioxidant, and apoptotic processes through multiple mechanisms. Crocin is considered a safe and effective therapeutic choice for patients with inflammatory conditions, although more research investigating its mechanisms and results acquired in clinical trials are needed.

• BMB Reports
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• v.28 no.3
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• pp.261-264
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• 1995

The lipids of a Korean native blood-sucking leech (Hirudo nipponia) were isolated and analyzed. Cholesterol, fatty acids, triglycerides, glycerylether diester and cholesteryl esters were found from epidennal extracts. The major fatty acids in the leech skin were $C_{16:0}$, $C_{18:0}$, $C_{20:1}$. $C_{20:3}$ components. These components were derived from cholesteryl esters, glycerides, fatty acids and other polar lipids. After 60 days fasting, cholesterol, fatty acids and triglycerides in the skin were reduced in number and the total fatty acid composition was changed slightly. The data of total fatty acids in fasted and fed leech showed that medium-chain fatty acids were more affected than long-chain fatty acids. Other trace fatty acids appeared to be decreased by fasting.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.89-89
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• 2006

Polyalkylene phosphates - polymers that are built on the repeating unit of the diester of phosphoric acid: -[OP(O)(OH)Oalkylene]-, are known to form backbones of nucleic and teichoic acids. Various synthetic ways will be reported for the synthesis of the bare chains, where "alkylene" in the formula above means mostly two or three methylene groups. Some other structures have also been prepared. Several applications of these polymers are to be discussed, namely as liquid membranes, as components of two-block copolymers (ionic-nonionic diblock dihydrophilic) used as modifiers of CaCO3 crystallization, and as components of the inorganic-polymer hybrid materials. Some other applications in the biomedical field will also be discussed.

• Biomolecules & Therapeutics
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• v.9 no.3
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• pp.143-155
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• 2001

Many attention has been focused on developing new chemotherapeutic agents for a treatment of cancer from natural products. From Carpesium divaricatum S. et Z. (Compositae), various monoterpenoid compounds were isolated and exhibited mild antitumor activity against human tumor cell lines. These facts prompted us to explore the structure-activity relationship of these compounds. The synthesis of monoterpenoid compound was accomplished by Fries rearrangement, Grignard reaction, elimination, allylic oxidation, esterification and epoxidation as key steps. The results of in vitro cytotoxicity (A549, SK-OV-3, SK-MEL-2, XF498, HCT15) of the synthesised compounds are as follows: First of all, epoxide moiety is prerequisite for cytotoxic activity in diester compound. Any kind of compounds with olefin or diol moiety instead of epoxide ring exhibited poor or mild cytotoxic activity respectively. Of o-acetoxy and isobutoxy epoxy esters, p-sub-stituted phenylacetate compounds exhibited high cytotoxic activities against SK-MEL-2 and HCT15.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2008.10a
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• pp.25-26
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• 2008

일반적인 분산염료, Phthalimide계 중간체로 사용한 분삼염료, Diester계 커플러만 이용한 분산염료와 비교한 Diester계 치환기를 이용한 분산 염료들은 R/C조건과 EtOAc와 증류수로 층분리하여 증류수층의 UV-Vis absorbance은 떨어지고 용해성은 증가한다. 그리고 Thiopene ring만 가진 염료와 비교한 염료들은 같은 파장에서의 UV-Vis absorbance은 떨어져 용해도는 증가하고 Thiopene ring과 Azo group의 분해에 의한 화합물 때문에 단파장에서의 UV-Vis absorbance가 크게 증가하여 염색 폐수의 색도를 감소시킬 수 있다.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2009.03a
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• pp.45-46
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• 2009

In this study, 12 azo disperse dyes based on phthalimide were synthesized including their precursors. The chemical structures of the dyes and the corresponding precursors were analyzed by the GC-MASS, $^1H$ NMR spectra and elemental analysis. The dyeability on PET, such as step dyeing and build-up properties and color fastness were examined using conventional exhaust dyeing procedures.