• Title/Summary/Keyword: Ureas

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Preparation and Comparison the Physical Properties of Polyurethane-Urea Using Biomass Derived Isosorbide (바이오매스 유래 이소소르비드를 이용한 폴리우레탄-우레아의 제조 및 특성 비교)

  • Park, Ji-Hyeon;Park, Jong-Seung;Choi, Pil-Jun;Ko, Jae-Wang;Lee, Jae-Yeon;Sur, Suk-Hun
    • Textile Coloration and Finishing
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    • v.31 no.3
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    • pp.165-176
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    • 2019
  • Polyurethane-ureas(PUUs) were prepared from 4,4'-methylenebis(cyclohexyl isocyanate) and various diols including isosorbide. Isosorbide is starch-derived monomer that exhibit a wide range of glass transition temperature and are therefore able to be used in many applications. PUU was synthesized by a pre-polymer polymerization using a catalyst. Successful synthesis of the PUU was characterized by fourier transform-infrared spectroscopy. Thermal properties were determined by differential scanning calorimetry, thermogravimetric analysis, and dynamic mechanical analysis. It was found that by tuning isosorbide content in the resin, their glass transition temperature(Tg) slightly decreased. Physical properties were also determined by tensile strength and X-ray diffraction. There is no significant differences between petroleum-derived diol and isosorbide in XRD analysis. Moreover, their physical and optical properties were determined. The result showed that the poly(tetramethylene ether glycol)/isosorbide-based PUU exhibited enhanced tensile strength, transmittance, transparency and biodegradability compared to the existing diols. After 11 weeks composting, the biodegradability of blends increased in ISB-PUU. The morphology of the fractured surface of blend films were investigated by scanning electron microscopy.

Synthesis and Antitumor Evaluation of N-Alkyl-N-Nitrosocarbamoyl-$\alpha$-Amino- and 3$\beta$-Amino-$\alpha$-Cholestane Derivatives (N-Alkyl-N-Nitrosocarbamoyl-3$\alpha$-Amino-와 3$\beta$-Amino-5$\alpha$-Cholestane 유도체들의 합성 및 항암작용 평가)

  • 김정균;최순규;조인섭;유동식;유성호;문경호
    • YAKHAK HOEJI
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    • v.29 no.2
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    • pp.62-69
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    • 1985
  • The isomeric intermediates, $3{\alpha}$and $3{\beta}-amino-5{\alpha}-cholestane required for the synthesis of N-nitrosoureas, N-(2-chloroethyl)-N-nitrosocarbamoyl-$3{\alpha}-amino-5{\alpha}$-cholestane (9), N-methyl-N-nitrosocarbamoyl-3${\alpha}-amino-5{\alpha}-cholestane$ (10), N-(2-chloroethyl)-N-nitrosocarbamoyl-$3{\beta}-amino-5{\alpha}-cholestane$: (7), and N-methyl-N-nitrosocarbamoyl-$3{\beta}-amino-5{\alpha}-cholestane$ (8) were obtained through the $LiAlH_{4}$ reduction of $5{\alpha}$-cholestan-3-one oxime, followed by the chromatographic separation: the assignment of the stereochemistry of both isomers were based on the shape and chemical shift of $C_{3}$-proton resonances on their NMR spectra and on the elution mobility on the TLC. The urea intermediates, N-(2-chloroethyl) carbamoyl-3.alpha.-amino-5.alpha.-cholestane (13), N-methylcarbamoyl-$3{\alpha}-amino-5{\alpha}-cholestane$ (14), N-(2-chloroethyl) carbamoyl-$3{\beta}-amino-5{\alpha}-cholestane (11) and N-methyl-$3{\beta}-amino-5{\alpha}$-cholestane (12) were prepared by the treatment of each isomers ($3{\alpha}$-amino-and $3{\beta}-amino-5{\alpha}$-cholestane) with alkyl isocyanates in anhydrous $CHCl_{3}$, and the corresponding nitrosoureas, 7-10 were obtained by the nitrosation of the ureas, 11-14, with AcOH (or HCOOH)/$NaNO_{2}$ in ice-cold condition. The inhibitory activity of the nitrosoureas, 7-10, and their intermediates, 12-14 towards the growth of L1210 murine leukemia cells, were examined. Among them, the compounds 9 and 10 exhibited high activity having $ED_{50}$ to be 5.5g/ml and 6.1g/ml, respectively.

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The Biological and Biochemical Characteristics of Staphylococcus epidermidis Isolated from Diseased Cultured Flounder, Paralichthys olivaceus (양식 넙치에서 분리한 Staphylococcus epidermidis의 생물학적 및 생화학적 특성)

  • Sim, Doo-Saing;Jung, Sung-Hee;Park, Hyung-Sook;Chun, She-Kyu
    • Journal of fish pathology
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    • v.7 no.1
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    • pp.23-36
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    • 1994
  • A total of 8 strains of Staphylococcus epidermidis isolated in land-marine tank system of Kyongnam and Kyongbuk. Prefecture were tested for the biological and biochemical characteristics. These strains were isolated from pathologic specimens of cultured flounder. Paralichthys olivaceus. Growth of the isolates was good on BHIA, HIA. Staphylococcus No. 110 and ETGP. Growth was good at NaCl concentration between 2.0 and 3.0%, about $30^{\circ}C$ and at pH values about 7.0. DNase and coagulase production were negative, and all isolates except FSJ-2 strain were positive in hemolysis. Urease was positive reaction, and novobiocin resistance was negative. Acid was produced anaerobically from glucose and maltose. All isolates except FSJ-19 strain produced weakly were negative in anaerobic acid production from mannitol. Acid was produced aerobically from glucose, fructose, galactose, sucrose, maltose and dextrine. But all isolates were not gas production. In characterization of clinically isolates, four different biotype codes were obtained when the all isolated were tested simultaneously. Four different antibiotic susceptibility patterns were obtained. On the basis of these characteristics, the isolates were identified as Staphylococcus epidermidis.

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Antioxidant Action of Reaction Mixtures of Gums Hydrolysates and Urea Derivatives (중합도별 gum류 가수분해 올리고당과 urea관련화합물과의 반응혼합물이 항산화능에 미치는 영향)

  • Kim, Sang-Woo;Park, Gwi-Gun
    • Applied Biological Chemistry
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    • v.47 no.4
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    • pp.384-389
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    • 2004
  • The purified ${\beta}-mannanase$ hydrolyzed various gums to mannose, ${\beta}-1,4-mannobiose$, $Gal^3Man_4$, and D.P 7 of galactosyl mannooligosaccharide, and isolated from the enzymatic hydrolysate for 24 hrs reaction by activated carbon column chromatography and Sephadex G-25 column chromatography. For the elucidate of antioxidant action of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ and DP 7 of galactosyl mannooligosaccharide and urea derivatives, coloration, reducing power, antioxidant activity and DPPH test were accomplished. The coloration was high at reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and urea. TLC of reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and ureas showed new reaction products, respectively. but except reaction mixture of ${\beta}-1,4-mannobiose$ and urea. The reducing power was high at reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and phenylthiourea. The reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and thiourea showed similar radical scavenging activities on DPPH to activity of AsA. The reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and thiourea, phenythiolurea shown strong antioxidative activites on the oxidation of linoneic acid.

A Study on the Evolution of 3, 4-DCA and TCAB in Some Selected Soils [Part I]-A New Method of Synthesizing $^{14}C-ring-labeled$ and Non labeled TCAB- (수종토양중(數種土壤中)에서 3, 4-DCA 및 TCAB의 변화(變化)에 관(關)한 연구(硏究)제1보(第一報)-$^{14}C$-환표식(換標識) 및 비표식(非標識) TCAB의 신합성방법(新合成方法)-)

  • Lee, Jae-Koo;Fournier, J-C.;Catroux, G.
    • Applied Biological Chemistry
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    • v.20 no.1
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    • pp.109-116
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    • 1977
  • Much attention has been paid to the fact that quite a few herbicides such as phenylcarbamates, phenylureas, and acylanilides form azo compounds known as carcinogens by virtue of the microoranisms in soil. In consequence, many investigators synthesized. TCAB, an azo compound, starting from 3,4-dichloronitrobenzene for the related studies. However, the authors were under the necessity of synthesizing $^{14}C-ring-labeled$ TCAB from $^{14}C-ring-labeled$ 3,4-DCA available, in addition to making up for the disadvantage of dechlorination in the reduction of 3,4-dichloronitrobenzene. The new method is as follows:TCAB, $^{14}C-ring-labeled$ and non-labeled, was produced by aerial oxidation of 3,4-DCA catalyzed by CuCl with pyridine as solvent at $60^{\circ}C$ for 5-12 hrs, giving 80.2% yield. The procedure forpurification was described in detail. The identities of TCAB isomers were confirmed by means of autoradiography, TLC, GLC, IR, and MS.

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The Reactivity and Regiochemical Effect of Nitrosonium Species in the Nitrosation of N-Methyl-N'-Substituted Phenylureas (N-메틸-N'-치환페닐우레아화합물들의 니트로소화 반응에 있어서 니트로소화 화학종의 반응성 및 위치화학적 영향)

  • Jack C. Kim;In-Seop Cho;Soon-Kyu Choi
    • Journal of the Korean Chemical Society
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    • v.35 no.3
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    • pp.240-248
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    • 1991
  • The regioselectivity in the nitrosation of seven N-methyl-N'-substituted phenylureas ($CH_3NHCONHC_6H_4-G$; G = H, p-CH$_3$, m-CH$_3$, m-CH$_3$O, p-F, m-F, m-Br) was examined using NaNO$_2$ and 4 different acids (diluted HCl, HCOOH, CH$_3$COOH, CF$_3$COOH). In all cases, the two regioisomeric products, N-nitroso-N-methyl-N'-substituted phenylureas (A) and N'-nitroso-N-methyl-N'-substituted phenylureas (B) were observed to be formed as major products and product ratios were determined by the integration of their methyl peaks in $^1$H-NMR. Electron donating substitutent(G) on phenyl of the ureas generally led to increase the ratio of B to A. The data have revealed that the relative sensitivity of the nitrosonium species (HONO, HCOONO, CH$_3$COONO, CF$_3$COONO) toward the change of electron density on nitrogen with phenyl substitutents are 1.00 : 0.93 : 0.78 : > ∼ 0.7.

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Herbicidal Activity and Persistency in Aqueous Solution of Ortho Disubstituted Benzenesulfonyl Urea Derivatives (새로운 Ortho 이치환 Benzenesulfonyl Urea 유도체의 제초활성과 수용액중의 잔류성)

  • Kim, Yong-Jip;Chang, Hae-Sung;Kim, Dae-Whang;Sung, Nack-Do
    • Applied Biological Chemistry
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    • v.38 no.6
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    • pp.570-576
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    • 1995
  • The new sixteen herbicidal N-2-(1-hydroxy-2-fluoroethyl)-6-substituted(X)-benzenesulfonyl-N'-4,6-dimethoxypyrimidinyl-2-yl urea derivatives(S) were synthesized and thier herbicidal activities$(pI_{50})$ in vivo against rice(Orysa Sativa L.), Barnyard grass(Echninochloa orizicola) and Bulrush(Scirpus juncoides) were measured by the pot test under paddy conditions. The structure activity relationship(SAR) were studied using the physicochemical parameters of ortho-substituents(X) and hydrolysis rate constant(logk) and herbicidal activities by the multiple regression technique. The SAR suggested that the herbicidal activities were more dependant on the hydrolysis rate constant(logk>0) than the steric constants $(Es, small width($B_4$) and length($L_1$). Among them, halogens(2 & 5), methyl(15) and non(H) substituent(1) showed higher herbicidal activity for weeds which was not tolerent to rise and weeds. The herbicidal activity was increased and the persistency in aqueous solution was decreased by electron donating(${\sigma}0<0$) groups as ortho-substituent(X). From the relationship equation between herbicidal activity and hydrolysis rate constant, it was assumed that the both reactions would be proceeds with similar process. And the conditions on the ortho substituents to show higher herbicidal activity and the persistency in aqueous solution were also discussed.

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Effects of Application of Controlled Release Fertilizer Blended with Different Nitrogen Releasing Latex Coated Ureas on Rice Growth and Grain Quality (질소 용출속도가 다른 피복요소를 혼합한 완효성비료 시용이 벼 생육 및 쌀 품질에 미치는 영향)

  • Lee, Dong-Wook;Park, Ki-Do;Park, Chang-Young;Kang, Ui-Gum;Son, Il-Soo;Park, Sung-Tae
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.52 no.3
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    • pp.311-319
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    • 2007
  • This study was conducted to estimate effects of application of controlled release complex fertilizer with latex coated urea (LCU-complex) on growth and grain quality of rice under direct seeded on dry paddy (DS) and transplanted on flooding paddy (TP). Three types of latex coated urea different nitrogen (N) releasing were LCU40, LCU80 and LCU100. The time of N releasing of LCU formulations in water at both 20 and $30^{\circ}C$ was faster in the order of LCU40, LCU80, LCU blend (LCU40, LCU80 and LCU100 was mixed in ratio of 2:2:1), and LCU100. The number of tillers and dry matter weight were great in order of LCU-complex 100% > LCU-complex80% > urea and plant height was not significant. Grain yields at LCU-complex80% in both DS and TP plot were similar to those of urea application. N recovery of LCU-complex80% and 100% was improved 8 and 6% compared to that of conventional urea split application in DS plot and 9 and 4% in TP. Content of protein of grain at applied LCU-complex was less 0.8% and $0.1{\sim}0.7%$ than that of urea in DS and TP, respectively. Content of amylose and Mg/K ratio in rice grain was not significant. Consequently application of LCU-complex blended types of coated urea different N releasing can be reduced 20% of N without yield reduction and improved grain quality compared with urea application.