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91.
Kajihara M Sugie T Maeda H Sano A Fujioka K Urabe Y Tanihara M Imanishi Y 《Chemical & pharmaceutical bulletin》2003,51(1):15-19
Drug release mechanism from silicone carrier differs depending on physicochemical properties of the drug. So far, there have been few reports on controlled release of insoluble drug and on simultaneous release of two kinds of water-soluble drugs. The purposes of this study are to establish methods for (1). continuous release of insoluble drug, and (2). release of two kinds of water-soluble drugs from silicone carrier. Polystyrene beads (PSTB) and proteins such as interferon (IFN) and human serum albumin (HSA) were used as model drugs. PSTB was released from silicone only when citric acid (CA) and sodium bicarbonate (SB) existed as additives. The release patterns of IFN and HSA were almost same in the case of matrix and covered-rod formulations, but double-layered formulation released them in different patterns. As far as we are aware, this is the first report on the release of insoluble drug from silicone and the controlled release of two kinds of water-soluble drugs. 相似文献
92.
A novel combined system of Yb(OTf)(3) with TMSCl or TMSOTf catalyzed an imino ene reaction. The reaction of N-tosylbenzaldimine (1) with alpha-methylstyrene (2) proceeded smoothly to give homoallylic amine 3 in the presence of a catalytic amount of Yb(OTf)(3) and TMSCl. This catalytic system was successfully applied to the imino ene reactions of various aldimines with alkenes. This new imino ene reaction provides a unique method for the three-component coupling reaction of an aldehyde, tosylamide, and alpha-methylstyrene in the presence of Yb(OTf)(3) and TMSOTf, to give the corresponding homoallylic amine. 相似文献
93.
Hiroyuki Akita Katsumi Kurashima Masako Nozawa Shigeo Yamamura Kenzi Seri Yorishige Imamura 《Tetrahedron: Asymmetry》1998,9(24):269-4340
Enantioselective acetylation of (±)-4-(1-hydroxyethyl)benzenesulfonamide 6 with ‘Acylase I’ (No. A 2156) from Aspergillus melleus in the presence of vinyl acetate gave (R)-4-(1-acetoxyethyl)benzenesulfonamide 7 (98% ee) and (S)-6 (98% ee). Both (S)-6 and (R)-7 were individually converted to the (S)-hydroxyhexamide 2 (>99% ee) and (R)-hydroxyhexamide 2 (>99% ee), respectively. The absolute configuration of a metabolite (−)-hydroxyhexamide 2 from acetohexamide 1 was found to be S based on unequivocal chemical methods including X-ray analysis. 相似文献
94.
Deguchi K Ishikawa M Yokokura T Ogata I Ito S Mimura T Ostrander C 《Rapid communications in mass spectrometry : RCM》2002,16(22):2133-2141
A new method providing enhanced sensitivity for the analysis of oligonucleotides using an on-line coupled system of reversed-phase high-performance liquid chromatography (RP-HPLC) and electrospray ionization ion-trap mass spectrometry (ESI-MS) has been developed. The presented method allows the use of the standard gradient elution of 0.1 M triethylammonium acetate (TEAA) buffer (adjusted to pH 7.0 with acetic acid) and acetonitrile that is typically used for the separation of oligonucleotides in RP-HPLC. An added feature of this method is the ability to combine and mix additional 0.1 M imidazole in acetonitrile after the separation column for improved ESI-MS performance. This is similar to the post-column reaction method in liquid chromatography (LC) and the liquid sheath flow method in LC/ESI-MS, both of which offer the advantage of not compromising the chromatographic separation conditions. The application of this new method is demonstrated to afford improved sensitivity for the analysis of oligonucleotides (20-50 mer) via on-line coupled HPLC/ESI-MS analysis and purification systems. 相似文献
95.
Yoshiko Okada Shinobu Kishi Yasuko Shishido Masako Kato 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(5):m171-m173
Dichloro(4,4′‐dipentyl‐2,2′‐bipyridine‐κ2N,N′)platinum(II), [PtCl2(C20H28N2)], adopts a discrete π–π stacking structure, where the alkyl chains are located in a random manner. In contrast, dichloro(4,4′‐diheptyl‐2,2′‐bipyridine‐κ2N,N′)platinum(II), [PtCl2(C24H36N2)], forms a layer structure comprised of alkyl chain layers and paired coordination sites, as observed for analogous complexes with longer alkyl chains. 相似文献
96.
97.
Yanisa Mittraphab Yhiya Amen Maki Nagata Masako Matsumoto Dongmei Wang Kuniyoshi Shimizu 《Molecules (Basel, Switzerland)》2022,27(2)
The extract from Entada phaseoloides was employed as active ingredients of natural origin into cosmetic products, while the components analysis was barely reported. Using LC-DAD-MS/qTOF analysis, eleven compounds (1–11) were proposed or identified from acetone extract of E. phaseoloides leaves (AE). Among them, six phenolic compounds, protocatechuic acid (2), 4-hydroxybenzoic acid (3), luteolin-7-O-β-d-glucoside (5), cirsimaritin (6), dihydrokaempferol (9), and apigenin (10), were isolated by various chromatographic techniques. Protocatechuic acid (2), epicatechin (4), and kaempferol (11) at a concentration 100 μM increased the HaCaT cells viability of the UVB-irradiated cell without any cytotoxicity effect and reduced the expression of COX-2 and iNOS inflammation gene. Moreover, compounds 2 and 4 could have potent effects on cell migration during wound closure. These results suggest that compounds 2, 4, and 11 from AE have anti-photoaging properties and could be employed in pharmaceutical and cosmeceutical products. 相似文献
98.
99.
100.
Yoshiyuki Kawase Seiji Yamaguchi Osamu Maeda Akemi Hayashi Ichihiro Hayashi Kazuko Tabata Masako Kondo 《Journal of heterocyclic chemistry》1979,16(3):487-491
Benzofuro[2,3-b]quinoline ( Ia ) and its 11-methyl derivative ( Ib ) were synthesized by demethylcyclization of 3-(o-methoxyphenyl)-1,2-dihydroquinolin-2-ones (VIa,b). Benzofuro[2,3-b]quinoline-11-carboxylic acid (Id) was synthesized by chlorination followed by the action of potassium hydroxide of a lactone (IX) prepared by demethyl-cyclization of 3-(o-methoxyphenyl)-2-oxo-1,2-dihydroquinoline-4-carboxylic acid (VIII). Isomeric benzofuro[3,2-c]quinoline (Ha) and its 6-methyl derivative (IIb) were synthesized by demethyl-cyclization of 3-(o-methoxyphenyl)-1,4-dihydroquinolin-4-ones (XIa,b). Both the methyl derivatives (Ib and IIb) were converted to the carboxylic acids (Id and IId) through condensation with benzaldehyde followed by oxidation. The benzofuroquinolines (Ia,b,d and IIa,b) thus obtained were oxidized to the corresponding N-oxides (IIIa,b,d and IVa,b). 相似文献