• Title/Summary/Keyword: carboxylate

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Synthesis of Aminophosphonate Derivatives Containing 7-Aminocephalosporanic acid (7-Aminocephalosporanic acid를 포함하는 Aminophosphonate유도체의 합성)

  • Kim, Sang Bum
    • Applied Chemistry for Engineering
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    • v.8 no.4
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    • pp.700-703
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    • 1997
  • 7-Aminocephalosporanic acid(7-ACA) was reacted with diphenyldiazomethane(DPM) to get diphenylmethyl 7-$\beta$-(O-ethylphthalimidomethylphosphony1)-3-acetoxymethyl-3-cephem-4-carboxylate. Diethyl phthalimidomethylphosphonate was chloridated with a slight excess of phosphorus pentachloride to the O-ethyl phthalimidoalkylphosphonochloridate. Previously unreported two compounds, diphenylmethy1 -7-$\beta$-(O-ethylphthalimidomethylphosphony1)-3-acetoxymethyl-3-cephem-4-carboxylate and diphenylmethyl-7-$\beta$-[O-ethylphthalimidoethylphosphonyl]-3-acetoxymethyl-3-cephem-4-carboxylate were synthesized by cupling reaction of DPM 7-ACA and O-ethyl phthalimidoalkylphosphonochloridate. All of the compounds including starting materials and reaction intermediates were characterized by $^1H$ NMR and FT-IR spectroscopy.

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Diastereotopic $^1H-NMR$ Spectrum of Ethyl Octahydro-2,3-dioxo-6a-hydroxy-1-benzyl-cyclopenta[b]pyrrole-3a-carboxylate (Ethyl Octahydro-2,3-dioxo-6a-hydroxy-1-benzyl-cyclopenta[b]pyrrole-3a-carboxylate의 부분입체이성질성 핵자기공명 스펙트럼)

  • 김동우;김태흥;박영규;윤경원;서원준
    • YAKHAK HOEJI
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    • v.39 no.2
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    • pp.205-209
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    • 1995
  • Methylene protons of benzyl and ethyl ester in ethyl 1-benzyl-2, 3-dioxo-cyclopenta[b]-pyrrole-3a-carboxylate (A) exhibited opposite$^{1}$H-NMR spectral patterns mutually between magnetic equivalence and nonequivalence depending on concentration and temperature. The diastereotopic spectral data of compound A were reported with brief interpretation.

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Synthesis and Characterization of Energetic Thermoplastic Elastomers based on Carboxylated GAP Copolymers

  • Lim, Minkyung;Jang, Yoorim;Kweon, Jeong-Ohk;Seol, Yang-Ho;Rhee, Hakjune;Noh, Si-Tae
    • Applied Chemistry for Engineering
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    • v.31 no.3
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    • pp.284-290
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    • 2020
  • Energetic thermoplastic elastomers (ETPEs) based on glycidyl azide polymer (GAP) and carboxylated GA copolymers [GAP-ETPE and poly(GA-carboxylate)-ETPEs] were synthesized using isophorone diisocyanate (IPDI), dibutyltin dilaurate (DBTDL), 1,4-butanediol (1,4-BD), and soft segment oligomers such as GAP and poly(GA-carboxylate). The synthesized GAP-ETPE and poly(GA-carboxylate)-ETPEs were characterized by Fourier transform infrared (FT-IR), gel permeation chromatography (GPC), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), universal testing machine (UTM), calorimetry and sensitivity towards friction and impact. DSC and TGA results showed that the introduction of carboxylate group in GAP helped to have better thermal properties. Glass transition temperatures of poly(GA-carboxylate)-ETPEs decreased from -31 ℃ to -33 ℃ compared to that of GAP-ETPE (-29 ℃). The first thermal decomposition temperature in poly(GA0.8-octanoate0.2)-ETPE (242 ℃) increased in comparison to that of GAP-ETPE (227 ℃). Furthermore, from calorimetry data, poly(GA-carboxylate)-ETPEs exhibited negative formation enthalpies (-6.94 and -7.21 kJ/g) and higher heats of combustion (46713 and 46587 kJ/mol) compared to that of GAP-ETPE (42,262 kJ/mol). Overall, poly(GA-carboxylate)-ETPEs could be good candidates for a polymeric binder in solid propellant due to better energetic, mechanical and thermal properties in comparison to those of GAP-ETPE. Such properties are beneficial to application and processing of ETPE.

Synthesis of Cyclohexyl 5-methylbicyclo[2,2,1]hept-2-ene-5-carboxylate (Cyclohexyl 5-methylbicyclo[2,2,1]hept-2-ene-5-carboxylate의 합성)

  • Lee, Yoon-Bae;Ko, You-Jin;Park, Hee-Kyoung
    • Proceedings of the KAIS Fall Conference
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    • 2011.05a
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    • pp.493-495
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    • 2011
  • cyclohexyl methacrylate와 cyclopentadiene을 반응하여 cyclohexyl 5-methylbicyclo[2,2,1]hept-2-ene-5-carboxylate를 합성하고 합성된 Norbornene계 화합물을 GC를 이용하여 그 비율을 측정하였고 Column Chromatography를 이용하여 endo와 exo를 분리해 $^1H-NMR$을 이용하여 endo와 exo 화합물의 구조를 확인하였다.

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Novel and Efficient Synthesis of Tetrazolo[1,5-b]-1,2,5-oxadiazepines as Antibacterial Activities from Ethyl 1-aminotetrazole-5-carboxylate

  • El-Badry, Susan M.;Taha, Mamdouh A.M.
    • Journal of the Korean Chemical Society
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    • v.55 no.6
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    • pp.974-977
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    • 2011
  • Ethyl 1-aminotetrazole-5-carboxylate (1) has been utilized to construct a variety of novel tetrazolo [1,5-b]-1,2,5-oxadiazepine derivatives which repesent a relatively little explored group with interesting antibacterial activities. The synthesized compounds were elucidated using IR, $^1H$ NMR and mass spectroscopic methods, besides elemental analyses.

Functional Analysis of Protein Chip Plate Using Silane Carboxylate Surface (실란 카르복실 표면을 사용한 단백질 칩 기판의 기능 분석)

  • 김지현;송예신;윤미영;피재호
    • Journal of the Korean institute of surface engineering
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    • v.37 no.4
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    • pp.215-219
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    • 2004
  • We fabricated protein chip plates coated with silane carboxylate. The silane compound was immobilized by hydrogen bond and/or other chemical bonds on the surface of the plate. The plates were then prepared by binding $Ni^{2+}$ to surfaces terminated with silane carboxylate groups. The carboxylic acid surface was generated by chemical oxidation of the terminal double-bond functions of the silane-deposited layer. The $Ni^{2+}$ ions on the surface reacted readily to His-tagged proteins. A significant increase in His-tagged protein adsorption was achieved on the surface terminated with silane carboxylate with longer alkyl chain, suggesting better availability of these protein chip plates for proteomic studies.

Study on Constituents of Paulownia tomentosa Stem(II) -synthesis of new furanquinone compound- (참오동나무 줄기의 성분연구(II) -새로운 furanquinone계 화합물의 합성-)

  • Jang, Seong-Ki;Park, You-Mie;Kim, Yeon-Soo;Kang, Kyung-Hwan;Kim, Yang-Suk;Kim, Bak-Kwang
    • YAKHAK HOEJI
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    • v.35 no.6
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    • pp.483-485
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    • 1991
  • A furanquinone substance(methyl 5-hydroxy-dinaphtho [1,2-2',3'] furan-7,12-dione-6-carboxylate) which has been isolated from the methanol extract of Paulownia tomentosa stem was synthesized by condensing 2,3-dichloro-1,4-naphthoquinone with methyl 1,4-dihydroxy-naphthalene-2-carboxylate in pyridine and identified by NMR, MS, UV, IR etc.

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Synthesis of Methyl 2, 6-Dimethyl-5-(1', 2'-Dioxo-2'-Ethoxyethyl)-4-(3'-Nitrophenyl)-1, 4 Dihydropyridine -3-Carboxylate

  • Suh, Jung-Jin;Hong, You-Hwa
    • Archives of Pharmacal Research
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    • v.13 no.3
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    • pp.257-260
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    • 1990
  • Hantzch's type reaction of methyl acetopyruvate (2a), methyl 3-aminocrotonate (3) and 3-nitrobenzaldehyde (4) led to dimethyl 3-acetyl-6-methyl-4-(3'-nitrophenyl)-2, 5-dicarboxylate (5a) and methyl 2, 6-dimethyl-5-(1', 2'-dioxo-2'-methoxyethyl)-4-(3' nitrophenyl)- 2, 5-dicarboxylate (5a) and methyl 2, 6-dimethyl-5-(1', 2'-dioxo-2'methoxyethyl_4-(3' nitrophenyl)1, 4-dihydropyridine-3-carboxylate (6a) in 26.7 and 9.2% yield, respectively. On the other hand, methyl 2, 60dimethyl-4-(3'-nitrophenyl)-1, 4-dihydropyridine 3-carboxylate (9) was acylated by ethyl oxaly chloride to give methyl 2, 6-dimethyl-5-(1', 2'-dioxo-2'-ethoxyethyl)-4-(3'-nitrophenyl)-a, 4-dihydropyridine-3-carboxylate (6b) in 76.8% yield.

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