• Title/Summary/Keyword: carboxylic acid

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Disordered Crystal Structure of Diflunisal $(C_{13}H_{8}F_{2}O_{3})$ (디플루니살의 불균일 결정구조)

  • Kim, Yang-Bae;Park, Il-Yeong
    • Journal of Pharmaceutical Investigation
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    • v.26 no.1
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    • pp.55-59
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    • 1996
  • The crystal structure of diflunisal, 2',4'-difluoro-4-hydroxy-3-biphenyl-carboxylic acid, was determined by single crystal X-ray diffraction technique. The compound was recrystallized from a mixture of acetone and water in monoclinic, space group C2/c, with $a\;=\;34.666(6),\;b\;=\;3.743(1),\;c\;=\;20.737(4)\;{\AA},\;{\beta}=\;110.57(2)^{\circ}$, and Z = 8. The calculated density is $1.324\;g/cm^3$. The structure was solved by the direct method and refined by full matrix least-squares procedure to the final R value of 0.045 for 1299 observed reflections. It was found that the molecules in the crystal are partially disordered, that is, the two equivalent conformers $(180^{\circ}$ rotated ones through C(1)-C(7)) are packed alternatively without regular symmetry or sequence. The two phenyl rings of the biphenyl group is tilted to each other by the dihedral angle of $43.3^{\circ}$. The carboxyl group at the salicylic moiety is just coplanar to the phenyl ring, and the planarity of this salicylic moiety is stabilized by an intramolecular hydrogen bond of O(3)-H(O3) O(2). The molecules are dimerized through the intermolecular hydrogen bonds at the carboxyl group in the crystal.

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New Antibacterial Peptide Analogs of 5-Aminobenzimidazoles (새로운 펩티드 유사체인 5-aminobenzimidazoles의 합성)

  • Gondal, Humaira Y.;Mashooda, H.;Ali, Muhammad
    • Journal of the Korean Chemical Society
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    • v.55 no.4
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    • pp.650-655
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    • 2011
  • Three new peptide analogs 5a-c were obtained through coupling of 5-Amino benzimidazoles 2a-c with L-phenylalanine. For the purpose ${\alpha}$-amino group was blocked with phthalic anhydride and activation of ${\alpha}$-carboxy group of phenylalanine was carried out by preparing phthaloyl-L-phenylalanyl chloride 4. After developing a successful peptide linkage, the phthaloyl group was removed by treating 5a-c with hydrazine hydrate to get free peptides 6a-c, purified through a column of Amberlite (IR-4B). All of these compounds 2a-c and 5,6a-c have been characterized on the basis of their IR, 1H NMR and EIMS analyses. Antibacterial activity of these compounds is also been reported.

DNA Topoisomerases I and II Inhibitory Activity of Constituents Isolated from Juglans mandshurica

  • Li, Gao;Lee, Sun-Young;Lee, Kyeung-Seon;Lee, Sung-Won;Kim, Sang-Hyun;Lee, Seung-Ho;Lee, Chong-Soon;Woo, Mi-Hee;Son, Jong-Keun
    • Archives of Pharmacal Research
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    • v.26 no.6
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    • pp.466-470
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    • 2003
  • Nine diarylheptanoids (1-9), one triterpene (10), one sesquiterpenoid (11), one naphthoquinone (12), four tetralones (13-16), one naphthalene carboxylic acid glucoside (17) and six naphthalenyl glycosides (18-23) were isolated from the roots of Juglans mandshurica Maximowicz (Juglandaceae), and their structures determined from the chemical and spectral data. Here, we report the inhibitory effects, on the DNA topoisomerases I and II activities, of all these compounds. Compounds 10 and 23 showed more potent inhibitory effects, on the DNA topoisomerases I and II (94.0 and 86.0% inhibitions at the concentration of 5 $\mu$ g/mL, respectively), than the positive control compounds, camptothecin and etoposide.

Cadmium and zinc removal from water by polyelectrolyte enhanced ultrafiltration

  • Ennigrou, Dorra Jellouli;Ali, Mourad Ben Sik;Dhahbi, Mahmoud;Mokhtar, Ferid
    • Membrane and Water Treatment
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    • v.5 no.3
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    • pp.183-195
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    • 2014
  • The efficiency of two metal ions (cadmium, zinc) removal from aqueous solutions by ultrafiltration (UF) and Polymer Enhanced Ultrafiltration (PEUF) processes were investigated in this work. The UF and PEUF studies were carried out using an ultrafiltration tangential cell system equipped with 5.000 MWCO regenerated cellulose. A water-soluble polymer: the polyacrylic acid (PAA) was used as complexant for PEUF experiments. The effects of transmembrane pressure, pH, metal ions and loading ratio on permeate fluxes and metal ions removals were evaluated. In UF process, permeate fluxes increase linearly with increasing pH for different transmembrane pressure, which may be the consequence of the formation of soluble metal hydroxyl complexes in the aqueous phase. In PEUF process, above pH 5.0, the Cd(II) retention reaches a plateau at 90% and Zn(II) at 80% for L = 5. Also, cadmium retention at different L is greater than zinc retention at pH varying from 5.0 to 9.0. In a mixture solution, cadmium retention is higher than zinc for different loading ratio, this is due to interactions between carboxylic groups of PAA and metal ions and more important with cadmium ions.

Dye-sensitized Solar Cells Based on Fluoran Leuco Sensitizers (플루오란 로이코 염료를 이용한 염료감응형 태양전지)

  • Jung, Hye-In;An, Byeong-Kwan
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.26 no.3
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    • pp.240-245
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    • 2013
  • The utilization of a fluoran leuco sensitizer, 2-anilino-6-dibutyl amino-3-methylfluoran (ODB-2), for dye-sensitized solar cells (DSSCs) was investigated through the examination of the adsorption of ODB-2 molecules onto the surfaces of porous titanium dioxide (titania, $TiO_2$) films and the photovoltaic properties of ODB-2-based DSSCs. Despite of the absence of the specific anchoring groups with titania, ODB-2 dye molecules were spontaneously adsorbed onto the titania surfaces because the lactone ring in ODB-2 was opened and changed into the carboxylic acid (-COOH) by releasing protons from the surfaces ($TiOH_2{^+}$) of titania, which consequently leads to the chemisorption reaction of ODB-2 molecules to the active sites of titania. DSSCs based on ODB-2 exhibited typical photovoltaic properties with an open-circuit voltage ($V_{OC}$) of 0.19 V, a short-circuit current ($J_{SC}$) of $0.30\;mA{\cdot}cm^{-2}$, a fill factor (FF) of 37%, and a conversion efficiency (PCE) of 0.02%.

Formulation of a novel bacterial consortium for the effective biodegradation of phenol

  • Dhanya, V.
    • Advances in environmental research
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    • v.9 no.2
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    • pp.109-121
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    • 2020
  • Phenol is frequently present as the hazardous pollutant in petrochemical and pesticide industry wastewater. Because of its high toxicity and carcinogenic potential, a proper treatment is needed to reduce the hazards of phenol carrying effluent before being discharged into the environment. Phenol biodegradation with microbial consortium offers a very promising approach now a day's. This study focused on the formulation of phenol degrading bacterial consortium with three bacterial isolates. The bacterial strains Bacillus cereus strain VCRC B540, Bacillus cereus strain BRL02-43 and Oxalobacteraceae strain CC11D were isolated from detergent contaminated soil by soil enrichment technique and was identified by 16s rDNA sequence analysis. Individual cultures were degrade 100 μl phenol in 72 hrs. The formulated bacterial consortium was very effective in degrading 250 μl of phenol at a pH 7 with in 48 hrs. The study further focused on the analysis of the products of biodegradation with Fourier Transform Infrared Spectroscopy (FT/IR) and Gas Chromatography-Mass Spectroscopy (GC-MS). The analysis showed the complete degradation of phenol and the production of Benzene di-carboxylic acid mono (2-ethylhexyl) ester and Ethane 1,2- Diethoxy- as metabolic intermediates. Biodegradation with the aid of microorganisms is a potential approach in terms of cost-effectiveness and elimination of secondary pollutions. The present study established the efficiency of bacterial consortium to degrade phenol. Optimization of biodegradation conditions and construction of a bioreactor can be further exploited for large scale industrial applications.

The Solvent Extraction of Uranium(VI) and Other Metal Ions with Pyrazolone Chelating Agents -The Studios on the Rad-Waste Treatment(1)- (킬레이팅 화합물에 의한 우라늄의 용매추출 -방사성 폐기물 처리 처분 연구(I)-)

  • Hun Hwee Park;Nak June Sung
    • Nuclear Engineering and Technology
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    • v.15 no.2
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    • pp.117-122
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    • 1983
  • The chelating agent with $\beta$-diketo funtional group, 1-phenyl-3-methyl-4-acyl-pyrazolone-5-one, has been used in separating and extracting radionuclides in a waste solution. The derivatives of this pyrazolone compound, prepared by different acyl groups, were synthesized and examined to figure out the extracting ability for Uranium (VI) and Zirconium (IV). The product prepared with succinic anhydride, called succinyl pyrazolone, showed excellent extraction for uranium (VI) in a chloroform solvent system. This result indicates that acyl pyrazolones having carboxylic acid group as a functional group forming $\beta$-diketo functionality are very selective for uranium (VI) and generally other metal ions with high valency.

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Reduction of Representative Organic Functional Groups with Gallane-Trimethylamine

  • 최정훈;오영주;김민정;황북기;백대진
    • Bulletin of the Korean Chemical Society
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    • v.18 no.3
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    • pp.274-280
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    • 1997
  • The rates and stoichiometry of the reaction of gallane-trimethylamine with selected organic compounds containing representative functional groups were examined in tetrahydrofuran solution under standardized conditions (THF, 0 ℃). And its reducing characteristics were compared with those of aluminum hydride-triethylamine(AHTEA). The rate of hydrogen evolution from active hydrogen compounds varied considerably with the nature of the functional group and the structure of the hydrocarbon moiety. Alcohols, phenol, amines, thiols evolved hydrogen rapidly and quantitatively. Aldehydes and ketones were reduced moderately to the corresponding alcohols. Cinnamaldehyde was reduced to cinnamyl alcohol, which means that the conjugated double bond was not attacked by gallane-trimethylamine. Carboxylic acids, esters, and lactones were stable to the reagent under standard conditions. Acid chlorides also were rapidly reduced to the corresponding alcohols. Epoxides and halides were inert to the reagent. Caproamide and nitrile were stable to the reagent, whereas benzamide was rapidly reduced to benzylamine. Nitropropane, nitrobenzene and azoxybenzene were stable to the reagent, whereas azobenzene was reduced to 1,2-diphenylhydrazine. Oximes and pyridine N-oxide were reduced rapidly. Di-n-butyl disulfide and dimethyl sulfoxide were reduced only slowly, but diphenyl disulfide was reduced rapidly. Finally, sulfones and sulfonic acids were inert to the reagent under the reaction.

Effect of Chemical Structures and Added Amounts of Humectants in Pigment Ink on Touch of Dyed Fabrics (안료 잉크 내 휴멕턴트의 화학구조와 첨가량이 염색 직물의 태에 미치는 영향)

  • Kim, Hyungjin;Park, Seongmin;Kwon, Woong;Jeong, Euigyung
    • Textile Coloration and Finishing
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    • v.34 no.1
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    • pp.10-19
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    • 2022
  • Humectants are chemical compounds which added to water based pigment inks for DTP (Digital Textile Printing) to prevent evaporation of water. The humectants usually have diol or triol type chemical structures and their -OH groups have possibility to react with functional groups of the binder polymers, such as ester, carboxylic acid, and urethane groups, acting as a crosslinking agent. The crosslinking reactions between polymer binders and humectants in inks can affect touch of the printed fabrics. In this regard, this study aims to investigate effect of chemical structures and added amounts of humectants in pigment ink on touch of dyed fabrics by using 1,6-hexanediol, ethylene glycol, diethylene glycol, and 1,4-buthanediol with various amounts added to the mixture of a black pigment and a polyurethane type binder. Then, color, rubbing strength, touch of the fabrics dyed with the prepared pigment inks were evaluated.

Metabolite Chemical Composition of the Bletilla striata (Thunb.) Reichb. f. Endophyte Penicillium oxalicum

  • Ran Liu;Xuehua Han;Jing Gao;Min Luo;Dale Guo;Guangzhi Wang
    • Mycobiology
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    • v.51 no.3
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    • pp.148-156
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    • 2023
  • Penicillium oxalicum strain can be isolated from the Bletilla striata (Thunb.) Reichb. f. tubers. Its solid-state fermentation products are concentrated by percolation extraction. Separation and purification have been conducted to the ethyl acetate extracts by preparative HPLC. Based on the use of spectrometry, we have determined 17 known compounds, 12,13-dihydroxy-fumitremorgin C (1), pseurotin A (2), tyrosol (3), cyclo-(L-Pro-L-Val) (4), cis-4-hydroxy-8-O-methylmellein (5), uracil (6), cyclo-(L-Pro-L-Ala) (7), 1,2,3,4-tetrahydro-4-hydroxy-4-quinolin carboxylic acid (8), cyclo-(Gly-L-Pro) (9), 2'-deoxyuridine (10), 1-(b-D-ribofuranosyl)thymine (11), cyclo-(L-Val-Gly) (12), 2'-deoxythymidine (13), cyclo-(Gly-D-Phe) (14), cyclo-L-(4-hydroxyprolinyl)-D-leucine (15), cyclo-(L)-4-hydroxy-Pro-(L)-Phe (16), uridine (17). Here, we report compounds 1-3, 5, 7-8, 11-12, 14-17 are first found and isolated from this endophyte.