• Title/Summary/Keyword: esterification

Search Result 413, Processing Time 0.023 seconds

Synthesis and Bioactivity of Quercetin Aspirinates

  • Lu, Chenjuan;Huang, Feng;Li, Zexin;Ma, Jinshuo;Li, Huanhuan;Fang, Lizhen
    • Bulletin of the Korean Chemical Society
    • /
    • v.35 no.2
    • /
    • pp.518-520
    • /
    • 2014
  • Hybrids of some natural compounds are promising to obtain new leads with good biological activities for drug discovery. Three quercetin aspirinates were synthesized by esterification of the 3-and 7-hydroxyl groups of quercetin with aspirin. Biological activities of these quercetin aspirinates were initially screened and showed better cytotoxic activities against tumor cell lines HL-60 and HepG2 and less scavenging activity against DPPH than the quercetin respectively.

Modeling and Simulation on a Direct Esterification Reactor for PET Polymerization and energy analysis (PET 직접 에스테르화 중합 반응기의 모델링 및 시뮬레이션과 에너지적 분석)

  • 김주열;권태인;여영구
    • Proceedings of the Korea Society for Simulation Conference
    • /
    • 2000.11a
    • /
    • pp.67-72
    • /
    • 2000
  • PET는 합성섬유, 필름, 음료수병, 성형 플라스틱 등의 다양한 용도를 가지고 있으며 특히 섬유 원료부분에서는 전세계의 약 40%이상을 차지하고 있는 상업적 입장에서 아주 중요한 소재이다.[1]그러나, PET 제조공정은 긴 반응시간과 높은 반응온도, 대용량의 다단계 공정시설을 필요로 하는 대표적인 에너지 다소비 공정으로서 현대의 치열한 고분자 제품의 시장경쟁 상황에서 에너지 투입량 감축을 위한 공정의 해석 및 개발과 그로 인한 생산원가의 절감이 필수적이다. 본 연구에서는 실제 공장에서 사용되는 단일 연속식 직접 에스테르화 반응기(CSTR Direct Esterification Reactor)를 모델링하고 Van Krevelen[2]의 Group contribution method로 계산된 올리고머의 열용량값을 이용하여 에너지 소모량을 계산하였다. 모델링 결과는 모두 실제 공장의 자료와 비교되었으며 가장 제어하기 쉬운 변수에 따른 반응물의 물성과 에너지 소모량을 분석하였다. 또한 압력이 일정한 조건 하에서 입력변화에 따른 반응기의 동적 모델링을 동시에 수행하였으며 투입에너지량과 반응기의 운전지표와의 관계를 분석하였다. 이러한 연구는 실제 공정분석과 최적화에 있어서 소모 에너지량을 고려한 보다 정확한 지표를 제시하고 에너지 사용의 효율성을 높이는 데 기여할 수 있다.

  • PDF

Synthesis of New Anthracyline Derivatives Containg Acetylsalicyclic or Palmitic Acid Moiety.

  • Rho, Young S.;Kim, Wan Jung;Park, Si Ho;Yu, Dong Jin;Gang, Heun Su;Jeong, Sun Ryang
    • Bulletin of the Korean Chemical Society
    • /
    • v.22 no.6
    • /
    • pp.587-592
    • /
    • 2001
  • The potential anticancer agents new anthracycline derivatives (2~9) have been synthesized from daunomycin (1a) and doxorubicin (1b) ad starting materials. Compounds 2 and 6 were prepared by the nucleophilic displacement type esterification of a 14-bromodaunomycin (1c) with a acetylsalicylic and palmitic acid in triethylamine, respectively. Compound 3 and 7 were obtained from daunomycin (1a) by direct amidation with the corresponding acids in the presence of EDCI and PP as esterification regents. Whereas 4 and 8 were prepared by reaction of doxorubicin (1b) with one equivalent of acetylsalicylic and palmitic acid using DCC/DMAP, respectively, 5 and 9 were obtained from 1b by acylation with two equivalents of the corresponding acids using EDCI/PP reagents.

Chiral Derivatization of Hydroxycarboxylic Acids Using 2,4,6-Trichlorobenzoyl Chloride as a Highly Efficient Regioselective Esterification Reagent for Gas Chromatography-Mass Spectrometry

  • Park, Jeong Hyeok;Han, Sang Yun
    • Mass Spectrometry Letters
    • /
    • v.11 no.4
    • /
    • pp.103-107
    • /
    • 2020
  • We report the application of 2,4,6-trichlorobenzoyl chloride (often referred to as Yamaguchi esterification reagent) for the selective derivatization of the carboxylic group for GC-MS with the sample preparation method optimized for GC-MS analysis. The reagent was shown to be capable of selectively turning the carboxylic group into a reaction center, i.e., anhydride, of which the further reaction was directed to a near complete formation of required esters by unique steric and electronic effects of the reagent. Using the developed method, the chiral separation of hydroxycarboxylic acids by GC-MS using non-chiral columns was successfully demonstrated.

Preparation of Anion Exchange Membranes of Cross-linked Poly((vinylbenzyl)trimethylammonium chloride-2-hydroxyethyl methacrylate)/Poly(vinyl alcohol) (가교결합한 Poly((vinylbenzyl)trimethylammonium chloride-2-hydroxyethyl methacrylate)/poly(vinyl alcohol) 음이온 교환막 제조)

  • Kim, Mi-Yang;Kim, Kwang-Je;Kang, Ho
    • Applied Chemistry for Engineering
    • /
    • v.21 no.6
    • /
    • pp.621-626
    • /
    • 2010
  • Anion exchange membranes can be used for reverse electrodialysis for electric energy generation, and capacitive deionization for water purification, as well as electrodialysis for desalination. In this study, anion exchange membranes of poly((vinylbenzyl) trimethylammonium chloride-2-hydroxyethyl methacrylate)/poly(vinyl alcohol) were prepared through the polymerization of (vinylbenzyl)trimethylammonium chloride and 2-hydroxyethyl methacrylate in aqueous poly(vinyl alcohol) solutions, esterification with glutaric acid, and cross-linking reaction with glutaraldehyde. We investigated electrochemical properties for the anion exchange membranes prepared according to experimental conditions. Ion exchange capacity and electrical resistance for the membranes were changed with a variation in the monomer ratio in polymerization. Water uptake and conductivity for the membranes decreased with an increase in the content of glutaric acid in esterification. The change in the time of crosslinking reaction with the formed film and glutaraldehyde affected electrochemical properties such as water uptake, conductivity, or transport number for the membranes. Chronopotentiometry and limiting current density for the anion exchange membranes prepared were measured.