• Title/Summary/Keyword: Phosphonate

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The Antiwear Performance of Dialkyl 3, 5-di-t-butyl 4-hydroxy Benzyi Phosphonates as a New Additive in the Four Ball Wear Test

  • Choi, Ung-Su;Kwon, Oh-Kwan
    • Tribology and Lubricants
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    • v.11 no.5
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    • pp.184-189
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    • 1995
  • The antiwear performance of dialkyl 3, 5-di-t-butyl 4-hydroxy benzyl phosphonates was investigated using a four ball wear test machine. Diethyl 3, 5-di-t-butyl 4-hydroxy benzyl phosphonate (DEP) and dibutyl 3,5-di-t-butyl 4-hydroxy benzyl phosponate (DBP) among them showed excellent antiwear performances compared with conventional additives, ZDDP and TCP as the bulk oil temperature and the sliding velocity increased. The surface analysis through an optical microscopy was conducted for tribological studies.

Design and Characterization of Low Viscosity Epoxy Based on Flame Retardant Phosphorus Epoxy (난연성 인계 에폭시를 기반으로 한 저점도 에폭시 설계 및 특성 분석)

  • Park, Jun-Seong;Woo, Je-Wan
    • Applied Chemistry for Engineering
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    • v.32 no.4
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    • pp.449-455
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    • 2021
  • Composite materials are substances that are configured to have excellent physical properties by combining the properties of a single substance, and are in the limelight as materials that exceed the performance of metals and polymers. However, it has the disadvantages of long cycle time and high unit price, and much research is being performed to overcome these disadvantages. In this study, we developed an epoxy resin curing agent that can shorten the time required for mass production of composite materials, and tried to expand the applicability of objections by imparting flame retardancy. The epoxy resin used as a basic substance utilized two types of bisphenol F and resorcinol structure, which was further modified using 9,10-dihydro-9-oxa-10-phosphaphenantrene-10-oxide (DOPO) to impart flame retardancy. Triethylphosphate (TEP) and bis [(5-ethyl-2-methyl-1,3,2-dioxaphosphorinan-5-yl)methyl] methyl phosphonate P,P'-dioxide (FR-001) were used as additives, seven kinds of compositions were blended, thermal characteristics (gelation time, glass transition temperature) and flame retardant performance were evaluated. We successfully developed an epoxy matrix that can be applied to high pressure resin transfer molding (HP-RTM) process.

Separation of the Enantiomers of β-Blockers Using Brush Type Chiral Stationary Phase Derived from Conformationally Rigid α-Amino β-Lactam

  • Pirkle, William H.;Lee, Won-Jae
    • Bulletin of the Korean Chemical Society
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    • v.31 no.3
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    • pp.620-623
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    • 2010
  • A brush type chiral stationary phase (CSP 2) derived from ${\alpha}$-amino ${\beta}$-lactam was prepared for the separation of the enantiomers of ${\beta}$-blockers. Compared to the CSP derived from ${\alpha}$-amino phosphonate (CSP 1), in general, the conformationally rigid CSP 2 showed greater scope and much enhanced enantioselectivity for the resolution of ${\beta}$-blockers. The effect of various salt additives on enantioseparation of ${\beta}$-blockers in the mobile phase was investigated. The unusual effect of temperature on the chromatographic behaviors was observed on CSP 2. It also afforded appreciable increases in enantioselectivity without significantly affecting resolution, as the column temperature was reduced.

Synthesis of Novel 2'(β)-Methyl-5'-deoxyapiose Nucleoside Phosphonic Acid Analogues as Antiviral Agents

  • Hong, Joon Hee
    • Journal of Integrative Natural Science
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    • v.8 no.1
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    • pp.48-55
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    • 2015
  • Novel 2'(${\beta}$)-methyl-5'-deoxyapiose purine phosphonic acid analogues were designed and synthesized from 2-propanone-1,3-diacetate. Condensation successfully proceeded from a glycosyl donor 9 under Vorbr${\ddot{u}}$ggen conditions. Condensation of aldehyde 14 with Wittig reagent [(diethoxyphosphinyl)methylidene] triphenylphosphorane gave the desired nucleoside phosphonate analogues 15. Ammonolysis and hydrolysis of phosphonates gave the nucleoside phosphonic acid analogue 17 and 19. The synthesized nucleoside analogues were subjected to antiviral screening against HIV-1. The adenine analogue 19 exhibited weak in vitro activities against HIV-1.

Synthesis of Novel 2'-Fluoro-5'-deoxyphosphonic Acids and Bis(SATE) Adenine Analogue as Potent Antiviral Agents

  • Shen, Guang Huan;Hong, Joon Hee
    • Bulletin of the Korean Chemical Society
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    • v.34 no.12
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    • pp.3621-3628
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    • 2013
  • Novel 5'-deoxythreosyl purine phosphonic acid analogues containing a 2'-electropositive moiety such as fluorine atom, were designed and synthesized from commercially available 1,3-dihydroxy acetone. Condensation successfully proceeded from a glycosyl donor 6 under Vorbr$\ddot{u}$ggen conditions and cross-metathesis gave the desired phosphonate analogues 7a, 7b, 17a and 17b. The synthesized nucleoside phosphonic acid analogues 13, 16, 23, 26, 28 were subjected to antiviral screening against HIV-1. The bis(SATE) adenine analogue 28 exhibited significant in vitro activities against HIV-1.

Chracteristics of Thermo and UV reactive Organophosphonate Flame Retardants

  • Kim, Tae-Gyeong;Park, Hui-Mun;Jeong, Byeong-Deok;Go, Sang-Hui
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2008.10a
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    • pp.135-136
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    • 2008
  • EU-Reach Regulation 대비 유해물질 대체약품 개발 프로그램인 SVHC(Substance of very high concern)로부터 환경친화적인 방염제의 스크리닝으로 LOI 30이상의 Halogen-free 유기계 Organo-Phosphonate 화합물들이 유력한 후보로 선별되었으며 여기에 반응형 저에너지 타입 아(메타)크릴계 광기능성기를 도입하여 에너지 절감형이면서 친환경적인 가공약제를 개발 하였다. 먼저 열경화형 타입중에서도 면섬유에 취급이 용이한 DMP(dimethylphosphite)를 출발물질로한 N-Methylol type의 열경화형 인/질소 타입 알코올 함유 면섬유용 방염제를 제조한후 -OH기에 광반응형 아크릴 기능성기를 도입하여 개시제와 함께 광경화 방염가공 후 물성에 관한 특성를 관찰 하였다.

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A Study on the Effect of Physico- Chemical Factors in Wear Mechanism in a Lubricated Concentrated Contact (I) (윤활시스템에서 마모메카니즘에 미치는 물리화학적 영향에 관한 연구(I))

  • 최웅수;권오관;문탁진;유영홍
    • Tribology and Lubricants
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    • v.4 no.1
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    • pp.36-42
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    • 1988
  • On the basis of the thermally-activated Wear theory, it is well estabilished that the secondary activated energy, which is mainly resulted from the exothermic reaction of hydrogen from thermal decomposition of the hydrocarbons at the high temperature and the high speed, caused catastropic failure. The new additive, viz., DEP was synthesized to reduce or eliminate the hydrogen effect at the contact junction. Through the thermal degrading and the thermodynamic consideration, the synthesized additive, viz., DEP showed the possibiliy as the hydrogen scavenger.

Synthesis and Anti-HCV Activity of 3',5'-cyclic SATE Phosphonodiester Nucleoside as a Novel Prodrug

  • Liu, Lian Jin;Seo, Rac-Seok;Yoo, Seung-Won;Choi, Jin;Hong, Joon-Hee
    • Bulletin of the Korean Chemical Society
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    • v.31 no.4
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    • pp.915-920
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    • 2010
  • A novel 2',4'-dimethyl carbocyclic adenosine 5'-phosphonic acid analogue (20) was prepared using acyclic stereoselective route from commercially available 4-hydroxybutan-2-one (4). To improve cellular permeability and enhance the anti-HCV activity of this phosphonic acid, a 3',5'-cyclic SATE phosphonodiester nucleoside prodrug (22) was prepared. The synthesized phosphonic nucleoside analogues, (20) and (22), were assayed for their ability to inhibit HCV RNA replication in a subgenomic replicon Huh7 cell line.

Studies of the Reactions between P-donors and [$(exo-6-R-\eta^5-2-MeO{\cdot}C_6H_5)Mn(CO)_2NO]PF_6$

  • Taeg Hwan Hyeon;Taek-Mo Chung;Young Keun Chung
    • Bulletin of the Korean Chemical Society
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    • v.10 no.6
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    • pp.500-503
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    • 1989
  • Synthetic studies have been carried out for the addition or substitution of phosphorus nucleophiles to the cation $[(exo-6-R-{\eta}^ {5_-}2-MeO-C_6H_5)Mn(CO)_2NO]PF_6,$ 2. $PPh_3$ reacts with 2 to yield the CO displaced product and $MePPh_2$ attacks the dienyl ring of 2 to yield the phosphonium adduct or the metal to give the CO displaced depending upon the reaction temperatures. Nucleophilic addition of HPPh2 to the dienyl ring of 2 gives a neutral substituted product. $P(OMe)_3$ reacts with 2 to yield a mixture of ring adduct and CO displaced product at room temperature. $At - 20^{\circ}C,\;P(OMe)_3$ attacks the dienyl ring of 2 to give a posphonium adduct, which underwent Arbuzov reaction. This reaction affords a new route to the phosphonate complexes.