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5-할로겐 치환 uracil 들의 4-Thiosugar Nucleosides의 합성 (제 1 보)
김정균,이억석,김창배,보벡크,윗슬러,Kim Jack C.,Lee Euk-suck,Kim Chang-bae,Bobek Miroslav,Whistlee Roy L. Korean Chemical Society 1975 대한화학회지 Vol.19 No.2
와 5-iodo-pyrimidine nucleoside 의 4'-thio 유도체들은 2,3,5-tri-O-aceytl-4-thio-D-ribofuranosyl chloride 와 5-halogeno-2,4-bis(trimethylsiloxy)pyrimidine의 chloromercury 유도체를 축합시킨후 보호작용기를 제거함으로써 합성하였다. 4'-Thio 유도체들의 생물학적 활성도는 예비시험에서는 이에 대응하는 4'-oxygen 유도체들과 큰 차이가 나지 않지만 4'-thio유도체가 비교적 더높은 활성을 가진다는 사실은 흥미로운 일이며 앞으로 생화학적인 고찰을 계속하는 것은 가치있는 일임을 보여주고 있다. The 4'-thio analogs of the 5-bromo-and 5-iodo-pyrimidine nucleosides were prepared by condensation of 2,3,5-tri-O-acetyl-4-thio-${\alpha},{\beta}$-D-ribofuranosyl chloride with the chloromercury derivatives of 5-halogeno-2,4-bis(trimethylsiloxy)pyrimidine, followed by the removal of the protecting groups. Although the biological activities of the 4'-thio derivatives are not greatly different from the corresponding 4'-oxygen analogs in this preliminary test, the fact that the 4'-thio analogs have comparableihigh activities, is of interest, and indicates the value of further biochemical examinations.
김정균,이억석,두렌보스,Jack C. Kim,Lee Euk-suk,Charles C. Chang,Norman J. Doorenbos Korean Chemical Society 1975 대한화학회지 Vol.19 No.3
The intermediate, 17${\alpha}$-methyl-4-aza-5${\alpha}$-androstan-17${\beta}$-ol(Ⅸ) required for the synthesis of 4-(${\beta}$-guanidinoethyl)-17${\alpha}$-methyl-4-aza-5${\alpha}$-androstan-17${\beta}$-ol(V) was obtained through a reaction of 17${\alpha}$-methyl-3,5-seco-4-norandrostan-17${\beta}$-ol-5-on-3-oic acid(VI) with ammonium hydroxide followed by two reductions(platinum dioxide with hydrogen and lithium aluminium hydride). Condensation of Ⅸ with chloroacetonitrile under anhydrous condition, followed by reduction of the nitrile with lithium aluminium hydride gave 4-(${\beta}$-aminoethyl)-17${\alpha}$-methyl-4-aza-5${\alpha}$-androstan-17${\beta}$-ol(XI). The reaction of XI with 2-methyl-2-thiopseudourea or 3,5-dimethylpyrazole-1-carboxamidine, or cyanamide provided the title compound, V. Relaxation of the nictitating membrane, in the absence of mydriasis, is considered to be evidence of adrenergic neurone blockade. Thus the test compound(V) resembles that of the classical adrenergic neurone blocking agents. 4-(${\beta}$-Guanidinoethyl)-17${\alpha}$-methyl-4-aza-5${\alpha}$-androstan-17${\beta}$-ol(V)을 합성하는데에 필요한 중간화합물인 17${\alpha}$-methyl-4-aza-5${\alpha}$-androstan-17${\beta}$-ol(IX)은 4단계를 거쳐 합성하였으며 IX을 chloroacetonitrile과 축합반응을 한후 $LiAlH_4$로서 환원하여 4-(${\beta}$-aminoethyl)-17${\alpha}$-methyl-4-aza-5${\alpha}$-androstan-17${\beta}$-ol(XI)을 얻었다. Tktle compound인 V은 3가지의 시약, 2-methyl-2-thiopseudourea,3,5-dimethylpyrazole-1-carboxamidine, cyanamide를 각각 XI와 반응시켜 좋은 수득률을 얻었다. 약리작용의 실험결과 V은 classical한 adrenergic neurone blocking agents와 유사하며 혈압강하제로서의 전망은 좋다고 예상된다.
김정균,조원제,보벡크,윗슬러,Jack C Kim,Won-Jei Cho,Miroslay Bobek,Roy L. Whistler Korean Chemical Society 1975 대한화학회지 Vol.19 No.6
Unusual pyrimidine nucleoside인 5-fluoro-4'-thiouridine과 5-Chloro-4'-thiouridine을 5-fluoro-와 5-chlorouracil의 2,4-bis(trimethylsilyl) 유도체들을 만든후, 축합반응하여 합성하였다. Leukemia 1210 cell과 Streptococcus faecium에 대한 기초 생물화학적인 예비시험에 의하면 5-fluoro-4'-thiouridine은 5-fluorouridine보다 억제효과가 월등하여 항암제로서의 전망여하는 앞으로의 임상 화학적인 결과로 구명될것 이라고 예상된다. The syntheses of anomeric mixtures of 1-(4-thio-${\alpha},{\beta}$-D-ribofuranosyl)-5-fluoro-and 5-chlorouracils from their corresponding bis(trimethylsilyl) derivatives of 5-halogenouracils and 2,3,5-tri-O-acetyl-4-thio-${\alpha},{\beta}$-D-ribofuranosyl chloride are described. Preliminary biochemical studies showed that in leukemia 1210 cells and Streptococcus faecium, the ${\beta}$-anomeric 5-chloro-4'-thionucleoside is not greatly different from the corresponding 4'-oxygen analog. However, the 5-fluoro-4'-thionucleoside showed a growth inhibitory effect more than that of the oxygen counterpart. The potential chemotherapeutic use of the analog is to warrant further study.
2-Oximino-1-indanone을 이용한 Pt(IV) ion의 정량에 관한 연구
김정균,유미경,원미숙,심윤보,고영심 대한약학회 1984 약학회지 Vol.28 No.2
A method is described for the spectrophotometric determination of platinum (IV) with 2-oximino-1-indanone based on solvent extraction of Pt:2-oximino-1-indanone complex. The 2-oximino-1-indanone reacted with Pt(IV) to form a dark-orange complex which shows a characterisic maximum absorption at 342nm. The optimum PH for the platinum extraction lies between 5.4~8.0. Beer's law obeys up to 0.98-16.3ppm of platinum (IV) and the molar absorption coefficient is $1.06{\times}10^{-4}L.mol^{-1}.cm^{-1}$. The relative standard deviation of the method was $\times2.1%$. The composition of the complex is estimated to be Pt : In= 1 : 1, by the mole ratio method and ion exchange resin experiment. The optimum condition for the determination of platinum has been studied in detail. The 2-oximin-1-indanone is found to be a selectivereagent for the determination of platinum, since the synthesixed 2-oximino-1-indanone did not react with other metals such as cobalt, cadmium, copper, manganese nickel, iron, lead and zinc, to form the complex. In this studies, we have also clarified Sindhwani and Singh's spectrophotometric determination data of various metals with acenaphthenequinone monooxime (Talanta 20,248, 1973), whose results were not correct.
아미노산으로부터 3-(2-Chloroethyl) hydantoin들의 합성과 그들의 항암작용 평가
김정균,윤이규,고영심,윤웅찬,박무영,문경호 대한약학회 1983 약학회지 Vol.27 No.4
Six hydantoin derivatives, 3-(2-chloroethyl) hydantoin (6a), 3-(2-chloroethyl)-5-isopropylhydantoin (6b), 3-(2-chloroethyl)-5-isobutylhydantoin (6c), 3-(2-chloroetbyl)5-(2-butyl) hydantoin (6d), 3-(2-chloroethyl)-5-benzylhydantoin (6e), 3-(2-chloroethyl)-5-(indolyl-3-methyl) hydantoin (6f), were prepared by the treatment of the corresponding salt of amino acids with 2-chloroethyl isocyanate in cold water, followed by refluxing in concentrated HCl solution. Anticancer activity of the synthesized hydantoin derivatives were examined on murine leukemia L1210 cells growing in Fischer medium. Among them, 3-(2-chloroethy)-5-isobutyl-hydantoin (6c) showed substantially low $ED_{50}$ value of $9.6{\mu}g/ml$.
Large variation in Young's modulus of carbon nanotube yarns with different diameters
김정균,서동석,강해용 한국물리학회 2021 Current Applied Physics Vol.21 No.-
Twist-spun carbon nanotube (CNT) yarns are composed of numerous CNTs and their bundles with entangled and twisted structures. In this paper, we studied the mechanical properties of CNT yarns. The individual CNT, a component of yarn, is well known to have an extremely high mechanical strength. However, CNT yarns are very flexible and relatively free to transform their shapes, showing the potential for application in the design of wearable devices. Since CNT yarns have two opposing characteristics at the same time, a wide range of Young’s modulus can be achieved by simply changing the geometrical structure while using the same fabrication process. We also suggest that CNT yarns can be utilized as the base material for several applications that require different stresses in a structure, such as bioimplants or foldable devices.