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Abachi S Derrick M Kooijman P Musgrave B Price LE Repond J Sugano K Blockus D Brabson B Brom J Jung C Ogren H Rust DR Akerlof C Chapman J Errede D Ken MT Meyer DI Neal H Nitz D Thun R Tschirhart R Baringer P Bylsma BG DeBonte R Koltick D Low EH McIlwain RL Miller DH Ng CR Shibata EI 《Physical review D: Particles and fields》1989,40(3):902-905
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A new caffeoyl quinic acid from aster scaber and its inhibitory activity against human immunodeficiency virus-1 (HIV-1) integrase 总被引:1,自引:0,他引:1
Kwon HC Jung CM Shin CG Lee JK Choi SU Kim SY Lee KR 《Chemical & pharmaceutical bulletin》2000,48(11):1796-1798
The phytochemical study of the aerial parts of Aster scaber Thunb. (Asteraceae) yielded a new caffeoyl quinic acid, (-) 3,5-dicaffeoyl-muco-quinic acid (2) and three known compounds, (-) 3,5-dicaffeoyl quinic acid (1), (-) 4,5-dicaffeoyl quinic acid (3), (-) 5-caffeoyl quinic acid (4). The structures were established by high resolution spectroscopic methods. The antiviral effects against HIV-1 integrase of the compounds was evaluated. (-) 3,5-Dicaffeoyl-muco-quinic acid (2) exhibited potent antiviral activity with an IC50 value of 7.0 +/- 1.3 microg/ml. 相似文献
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Yun SH Sohn BH Jung JC Zin WC Lee JK Song O 《Langmuir : the ACS journal of surfaces and colloids》2005,21(14):6548-6552
Hexagonal arrangement of iron oxide nanoparticles was fabricated by utilizing a single-layered film of diblock copolymer micelles. The synthesis was directly performed on the solid substrate by oxygen plasma with preserving the dimensional order of micelles so that separate procedures for synthesis and deposition of nanoparticles were not necessary. Since the oxygen plasma treatment also eliminated polymers, pure patterns of iron oxide nanoparticles were obtained. Moreover, easy control over the size of nanoparticles enabled us to selectively create a ferrimagnetic or a superparamagnetic pattern of iron oxide nanoparticles without altering the fabrication process. 相似文献
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Chan?Yoon?Jung Hoe?Jin?Hah Seung?Hoon?Han Hong-Woo?Park Sang?Man?KooEmail author 《Journal of Sol-Gel Science and Technology》2005,33(1):81-85
Tin oxide-doped hybrid particles were prepared by a wet chemical process with organic-inorganic (phenyl/silica) hybrid particles in an alcoholic solution. The phenyl/silica hybrid particles, with a diameter of ca. 790 nm were used as a new support material for tin oxide (SnO2) particles from tin(IV) chloride. The surface of the particles was modified via nitration of aromatic groups in the particles, to promote formation of the tin oxide coating on the particles. The thickness and surface morphology of the tin oxide layer coated on the nitrated-phenyl/silica hybrid particles could be controlled by varying the tin(IV) chloride concentration and reaction time. The size and morphology of the resultant particles were investigated with field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The particles obtained were also characterised by infrared (FTIR) and solid-state 13C magic angle spinning nuclear magnetic resonance (13C-CP/MAS NMR) spectroscopy. The effect of processing parameters on the crystallinity and structure of the doped hybrids were confirmed by X-ray diffraction (XRD) patterns. 相似文献
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Immobilized polysiloxane-anchored permethyl-β-cyclodextrin (Chirasil-Dex) with a cyclodextrin content of approximately 30 % by weight, previously employed as a versatile chiral stationary phase for the separation of enantiomers by GC, has been used for the separation of enantiomers by capillary supercritical fluid chromatography (SFC). A considerable number of racemates could be resolved, e.g. aromatic alcohols, amino alcohols (TFA derivatives), and underivatized acids. Many pharmaceutical compounds were among those analyzed, including several NSAIDs (e.g. ibuprofen and ketoprofen), a steroidal drug (nor-gestrel), a barbiturate (hexobarbital), and others. Among the racemates resolved were many which cannot be analyzed by GC owing to low volatility or decomposition at elevated temperatures. For two racemates, analysis temperature and mobile phase density were systematically varied to give constant analysis times or capacity factors k. Low temperatures (ca 60 °C) yielded the best separation in term of separation factor, α, or resolution, Rs, even though higher densities had to be used. In comparison with GC, capillary SFC was able to furnish higher separation factors and similar resolution. The applicability of capillary SFC for the analysis of mixtures of cyclodextrin derivatives, e.g. those used in the synthesis of Chirasil-Dex, was, furthermore, demonstrated. 相似文献