• Bulletin of the Korean Chemical Society
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• 제4권2호
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• pp.72-76
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• 1983

Cephaloglycin was synthesized directly from D-${\alpha}$ -phenylglycine methyl ester and 7-aminocephalosporanic acid using whole cell enzyme of Xanthomonas citri (IFO 3835). Some optimal conditions for cephaloglycin synthesis were investigated, and yield improvements for its production by several methods were attempted. Using the whole cell enzyme system, the reaction kinetic model for cephaloglycin synthesis is proposed, and the kinetic constants for D-${\alpha}$ -phenylglycine methyl ester hydrolysis, cephaloglycin synthesis, and cephaloglycin hydrolysis were determined. The $K_m$ values of D-${\alpha}$-phenylglycine methyl ester, 7-aminocephalosporanic acid, and cephaloglycin were 11 mM, 24 mM, and 167 mM, and $K_i$ value of D-${\alpha}$-phenylglycine was 15 mM, respectively. The pattern of product inhibition was found to be competitive one.

• Korean Journal of Chemical Engineering
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• 제35권11호
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• pp.2296-2302
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• 2018

Internally plasticized PVC was prepared via chemical reaction of azide PVC and alkynyl group containing castor oil methyl ester. The chemical structure of alkynyl group containing castor oil methyl ester and internally plasticized PVC was characterized with FT-IR and $^1H$ NMR. Properties of internally plasticized PVC, including thermal stability, tensile tests and resistance to extraction in different solvents, was investigated. The results showed that alkynyl group containing castor oil methyl ester, as internal plasticizer of PVC, not only decreased the $T_g$ of PVC from $84.6^{\circ}C$ to $41.6^{\circ}C$ efficiently, but also presented no plasticizer loss in five different solvents. The tensile tests showed that elongation at break and tensile strength of internally plasticized PVC was 353.8% and 18.1 MPa. The internally plasticized PVC has potential application in replacing the traditional PVC material in PVC products with high durability.

• 대한화학회지
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• 제44권3호
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• pp.290-293
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• 2000

• Bulletin of the Korean Chemical Society
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• 제22권11호
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• pp.1173-1174
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• 2001

• 대한화학회지
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• 제48권4호
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• pp.385-393
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• 2004

Benzofuroxan과 ethyl acetoacetate를 반응시켜 2-ethoxycarbonyl-3-methylquinoxaline 1,4-dioxide (8)를 합성하고, 이것을 hydrazine hydrate 또는 selenium dioxide와 반응시켜 2-hydrazinocarbonyl-3-methylquinoxaline 1,4-dioxide (9) 또는 2-ethoxycarbonyl-3-formylquinoxaline 1,4-dioxide (10)를 합성하였다. 화합물 9를 alkanoyl chloride류, benzoyl chloride류, heteroacyl chloride류 및 benzenesulfonyl chloride류와 반응시켜 3-methyl-2-(substituted hydrazinocarbonyl)quinoxaline 1,4-dioxide류 (11-14)를 합성하였다. 화합물 9를 sodium nitrite와 반응시켜 2-azidocarbonyl- 3-methylquinoxaline 1,4-dioxide (15)를 합성한 다음, 이것을 디옥산/알코올류 용매하에서 환류시켜 Curtius 자리옮김반응에 의한 N-(3-methyl-1,4-dioxoquinoxalin-2-yl)-alkyl carbamate류 (16)를 합성하였다. 그리고 화합물 15를 치환 아닐린류와 반응시켜 2-(3-substituted phenylureido)-3-methylquinoxaline 1,4-dioxide류 (17)를 합성하였다. 한편 화합물 10을 benzoic hydrazide 또는 치환 아닐린류와 반응시켜 quinoxaline 1,4-dioxide류 (18, 19)를 각각 합성하였다. 그리고 합성한 화합물들에 대한 제초력과 살균력도 조사하였다.

• 한국식품과학회지
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• 제26권6호
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• pp.679-682
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• 1994

마늘외 휘발성 함황성분을 용매추출 및 수증기 증류법에 의하여 추출하여 GC와 GC/MS에 의하여 분리 통정하고 건조온도에 따른 이들의 함량 변화틀 조사하였다. 핵산 추출물에서 8종, 수중기증류물에서 11종의 향기성분을 동정하였으며 이들 중 diallyl disulfide와 diallyl trisulfide, allyl methyl trisulfide가 대부분을 차지하였다. 건조온도가 중가함에 따라 마늘외 휘발성 함황성분은 핵산 추출물에서 $40{\sim}75%$까지 감소하였고 수중기 증류물에서는 $10{\sim}20%$ 정도 감소하였다. 휘발성 함황화합물중 diallyl disulfide, allyl methyl trisulfide의 함량은 크게감소한 반면 diallyl trisulfide의 함량은 비교적 적게 감소하였다.

• 한국환경과학회지
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• 제6권1호
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• pp.45-52
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• 1997

Methyl methanesulfonate (MMS) was fed to Drosophila melnogaster in order to investigate its toxic capability at developmental and adult stages, and the hereditary effect of toxicity and the potency for induction of sex-linked lethal mutation during the slyer-matogenesis by the means of an attached-X method. In the control group, the egg to adult viability of D. melnogaster was 95.2%, while 3. 5mM and 5.0mM treated groups were 90.0% and 84.1%, respectively. In the case of their progenies (Fl), the viability was 96.9% in the control group, while 3.5mM and 5.0mM treated groups were 54.5% and 1.6%, respectively. Therefore, these differences between two generations show significant physiological toxic effects in the next generation. In the parental generation, the developmental time was calculated 11.05 days in the control group, 12.43 days In 3.5%mM treated group, and 13.23 days in 5.0mM. In the case of Fl it was estimated 10.35 days in the control group, and 11.43 days In 3.5mM treated group. Compared with the control groups In two generations, the developmental time generally delayed as the dose of MMS increased. As to the sex-ratio, there was no differences between the control and MMS treated groups. The toxic values of adult stage showed which increased the frequency of mortality with MMS concentrations. The mortality at 120hr In the control group was 1.67% and it in 0.5mM MMS treated group 3.33%. In 2.5mM MMS treated group, it was 33.3% at 72hr, and it 95% at 120hr The increase of the morality was shown from 72hr in 4.0mM treated group which was 100% at 96hr. There was the concentration-dependent induction of sex-linked lethal mutation during the spermatogenesis by means of an attached-X method, MMS had more pronounced effect in sperm and spermaid stages in D. melnogaster.

• 한국산학기술학회논문지
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• 제11권1호
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• pp.228-233
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• 2010

Methyl hydrogen polysiloxne으로 처리한 ZnO, fumed $SiO_2$와 다양한 망간 전구체를 이용하여 서브마이크로미터 크기를 갖는 망간이 도핑된 $Zn_2SiO_4$ 형광체 입자를 고상법으로 제조하였다. 결정화와 광발광 특성은 XRD, SEM, PL스펙트라를 이용하여 분석하였다. 고상법으로 제조한 망간 도핑된 $Zn_2SiO_4$는 methyl hydrogen polysiloxne 처리한 ZnO의 분산과 응집 때문에 $1000^{\circ}C$에서 성공적으로 얻어졌고, 진공자외선 여기하에서 제조된 입자의 최대 PL강도는 0.02mol Mn, $1000^{\circ}C$에서 확인되었다.

• 한국식품저장유통학회지
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• 제12권1호
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• pp.68-74
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• 2005

본 연구에서는 우리나라의 전통차의 계승과 새로운 식품의 개발하고자 생강나무의 잎을 이용한 차의 제조방법에 따른 향기성분의 변화를 조사하였다. 재차방법에 따른 향기성분은 덖음차 81종, 찐후덖음차 78종, 자연건조차 88종, 발효차 86종, 찐차 72종 및 인공건조차 89종의 분리할 수 있었다. 생강나무 잎차의 향기성분은 $\beta-piepne$을 비롯한 hydrocarbone류가 45종이 동정되었으며, 가장 많은 종류의 성분이 분포되었다. Alcohol류는 L-linalool, n-octanoal, phenyl acetaldehyde, $(-)-\alpha-terpineol$, elemol, cholest-5-en-3-ol, 등 16종, 2-nitro-2(3-hydroxybuthyl) -clododexanone, 3-(3-butenyl)-2,3-epoxy-cyclohexanone, 2-ethyl-2-propyl- cyclo-hexanone 등 11종의 ketone류가, phenyl acetaldehyde, tetradecanal, 10-undecanal, 4-Bromo-2- methylbutanal 등 8종의 aldehyde류가 동정되었다. 또한 ester류는 methyl 9, 12, 15-octadecatrienate, didodecyl phthalate, 1,2-benzenediccar-baboxy acid-bis(2-ethylhexyl) ester 3종류가 동정되었고, 또한 phenol류는 2,6-bis(1,1-dimethylethyl)-4-methyl-phenol이 동정되었다.

• 대한화학회지
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• 제46권4호
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• pp.330-336
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• 2002

새로운 ${\alpha},{\beta}$-불포화Carboxanilide계열의 살균제를 개발을 목적으로 4-acetyl-3-methyl-N-phenyl-1,4-thiazine-2-Carboxamide(6)의 합성에 대하여 기술하였다. Dihydro-1,4-thiazine methyl ester 11을 산화하여 생성된 sulfoxide 7을 Pummerer 반응하여 $\alpha$-acetoxy dihydro-1,4-thiazine 10a를 얻었다. 반며에 Dihydro-1,4-thiazine Carboxanilide sulfoxide14는 동일한 반응조건 하에서 중간체 sulfonium ion의 carboxanilide기가 관여한 vinylogous Pummerer 반응의 전위에 의하여 중간체를 15를 통하여 acetoxymethyl dihydro-1,4-thiazine 18이 생성되었다. 1,4-Thiazine carboxanilide 6은 $\alpha$-acetoxy dihydro-1,4-thiazine 10a를 산촉매로 처리한 다음 생성된 21a를 가수분해하고 아닐린과 결합하여 합성하였다