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31.
Ywu-Jang Fu Shin-Shing Shyu Fu-Hu Su Pih-Chen Yu 《Colloids and surfaces. B, Biointerfaces》2002,25(4)
The water-soluble anti-cancer drug, 5-fluorouracil (5-fluoro-2,4-pyrimidinedione) (5-FU) is encapsulated into biodegradable co-poly (
-lactic/glycolic acid) (PLGA) using the spray drying method for the development of long-lasting controlled release systems. In this study, the effects of both polymeric composition and technological parameters on release profiles of 5-FU were investigated. The degradation of various microspheres was also investigated. The mixture of dichloromethane/chloroform/methanol (1:1:2 v/v) instead of dichloromethane/chloroform (1:1 v/v) resulted in the modification of morphology, while the physical structure of the microsphere varied from a porous PLGA microsphere to a dense PLGA microsphere. The results show that the average diameter was 2 μm and the anti-cancer drug loading of microspheres approached approximately 8% (w/w). In addition, the lactide/glycolide ratio of the polymer is an important parameter for controlling the release profile of the entrapped anticancer drug. Our results indicate that the mixture solvent using the spray drying method was more efficient than emulsification solvent diffusion. 相似文献
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Cheng Ming-Jen Wu Ming-Der Hsieh Sung-Yuan Chen Chung-Yi Chen Jih-Jung Kuo Yueh-Hsiung 《Chemistry of Natural Compounds》2022,58(4):653-655
Chemistry of Natural Compounds - One new natural product, cadinane-type sesquiterpenoid, (±)-(2S*,3S*)-dihydroxy-α-corocalene (1), has been isolated from the endophytic fungus Curvularia... 相似文献
34.
Wei‐Lin Su Hsiu‐Ping Huang Wei‐Ting Chen Wen‐Yi Hsu Hsi‐Yen Chang Szu‐Yu Ho Shao‐Pin Wang Shin‐Guang Shyu 《中国化学会会志》2011,58(2):163-173
Carbonyls' 2π orbital populations, [2π], in W(CO)5L {L = PPh3, PPh2Me, PPhMe2} have been determined by NMR spin‐lattice relaxation techniques. Experimental values of axial [2π], compared with those reported for PMe3 and P(OMe)3, reveal that PMe3 is a slightly better π‐acid than PPh3. Through space interactions between carbonyl and phenyl groups are insignificant since values of [2π] do not vary significantly in the series of phosphines, going from PMep3 to PPh3. Natural bond orbital (NBO) studies indicate that π‐accepting capabilities for these phosphines are primarily governed by the nature of P‐C anti‐bonding, σ*P‐C. Compared with PPh3, the better π‐accepting σ*P‐C, as well as the better s‐donating lone‐pair LP(P), in PMe3 can both be explained by the higher extents of rehybridization of the coordinated phosphorus atom. Based on this rehybridization argument, the NBO predicted order of increasing π‐acidic strengths PPh3 < PPh2Me < PPhMe2 < PMe3, which cannot be clearly distinguished by NMR experiments, is ascribed to the same NBO trend of σ‐donating capabilities in a synergistic manner. Effects of coordination on P‐Y (Y = C, O, F) bonding strengths in phosphines (or phosphites) are depending on two conflicting effects: rehybridization of LP(P) and the hyperconjugative‐like dπ → σ*P‐Y back‐donation. 相似文献
35.
Wu Ming-Der Chen Jih-Jung Cheng Ming-Jen Hsieh Sung Yuan Chang Chih-Zen Kuo Yueh-Hsiung 《Chemistry of Natural Compounds》2022,58(5):839-841
Chemistry of Natural Compounds - A new cyclohexan-1-one, named xylariaone (1), was isolated from the fungal strain Xylaria sp. 12F0758. Its structure was elucidated by spectroscopic analyses,... 相似文献
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Chen Hui-Ming Huang Chien-Ming Chen Li-Chai Yang Chang-Syun Chang Tsung-Hsien Chen Chun-Lin Sung Ping-Jyun Kuo Wen-Lung Cheng Ming-Jen Hsiao Jen-Wen Chen Jih-Jung 《Chemistry of Natural Compounds》2022,58(3):496-500
Chemistry of Natural Compounds - A new triterpenoid, methyl 2α-(4-hydroxybenzoyl)oxy-3β-hydroxy-urs-12-en-28-oate (1), has been isolated from the leaves of Eriobotrya deflexa f. deflexa,... 相似文献
37.
Ficumone, a 2-oxetanone isolated from the fruits of Synsepalum dulcificum, has been characterised as (R*)-4-hydroxy-2-oxetanone by means of spectroscopic methods. 相似文献
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2,4′-Bipyridines 4a, 4c, 4d and 3,4′-bipyridines 4b, 4e, 4f, 4g, 4h are obtained in modest yield by the addition of organocuprate reagents derived from bromopyridines 2a-h to N-ethoxycarbonylpyridinium chloride 1 followed by air oxidation. 相似文献
40.
Simultaneous determination of sweeteners and preservatives in preserved fruits by micellar electrokinetic capillary chromatography 总被引:1,自引:0,他引:1
A micellar electrokinetic capillary method for the simultaneous determination of the sweeteners dulcin, aspartame, saccharin, and acesulfame-K and the preservatives sorbic acid; benzoic acid; sodium dehydroacetate; and methyl-, ethyl-, propyl-, isopropyl-, butyl-, and isobutyl-p-hydroxybenzoate in preserved fruits is developed. These additives are ion-paired and extracted using sonication followed by solid-phase extraction from the sample. Separation is achieved using a 57-cm fused-silica capillary with a buffer comprised of 0.05 M sodium deoxycholate, 0.02 M borate-phosphate buffer (pH 8.6), and 5% acetonitrile, and the wavelength for detection is 214 nm. The average recovery rate for all sweeteners and preservatives is approximately 90% with good reproducibility, and the detection limits range from 10 to 25 microg/g. Fifty preserved fruit samples are analyzed for the content of sweeteners and preservatives. The sweeteners found in 28 samples was aspartame (0.17-11.59 g/kg) or saccharin (0.09-5.64 g/kg). Benzoic acid (0.02-1.72 g/kg) and sorbic acid (0.27-1.15 g/kg) were found as preservatives in 29 samples. 相似文献