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1.
Two novel aromatic glycosides were obtained from Puerariae Radix and their chemical structures were characterized. 相似文献
2.
Hepatoprotective and hepatotoxic actions of oleanolic acid-type triterpenoidal glucuronides on rat primary hepatocyte cultures 总被引:2,自引:0,他引:2
Kinjo J Okawa M Udayama M Sohno Y Hirakawa T Shii Y Nohara T 《Chemical & pharmaceutical bulletin》1999,47(2):290-292
The protective effects of oleanolic acid-type saponins and their derivatives on in vitro immunological liver injury of primary cultured rat hepatocytes were studied. A known antihepatotoxic saponin (chikusetsusaponin IVa, 1) showed hepatoprotective activity in this model. Although a rhamnosyl derivative (2) of 1 similarly showed hepatoprotective activity, its prosapogenin (5) did not show any hepatoprotective activity. On the contrary, 5 exhibited cytotoxicity toward liver cells. In the absence of antiserum, monodesmosyl saponins showed hepatotoxicity, while the bisdesmosyl saponins except for 1, did not show such hepatotoxicity. In order to clarify the effects of the sugar residues at C-3 and C-28 responsible for hepatoprotective and hepatotoxic actions, oleanolic acid 3-O-glucuronide (2a) and oleanolic acid 28-O-glucoside (2b) were prepared and tested. 2b showed neither hepatoprotective action nor hepatotoxicity. In contrast, 2a was effective at 90 microM on hepatoprotection, although it showed strong hepatotoxicity. Oleanolic acid (2c) itself showed both hepatoprotective action and weak hepatotoxicity. Therefore, the hepatoprotective activity of these types of saponins could represent a balance between hepatoprotective action and hepatotoxicity. 相似文献
3.
Masunobu Maeda Yoshiaki Kinjo Osamu Hisada Kaname Ito 《Journal of solution chemistry》1990,19(10):1019-1027
The Pitzer approach has been applied to the evaluation of dissociation constants of ammonium ion in lithium perchlorate and lithium chloride-sodium chloride mixed solutions at 25°C. The calculated values showed good agreement with the observed values, provided all the higher-order interaction terms ('s and 's) concerned were introduced. The unknown (NH4LiClO4) value was determined from the isopiestic measurements of NH4ClO4–LiClO4 mixed solutions. Parameters in the Pitzer formalism for ammonia-ion interactions involved in LiCl and NaCl media were determined by use of the activity coefficients of ammonia measured in LiCl–NaCl mixed solutions by a transpiration method. 相似文献
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5.
Y Ding R H Tian J Kinjo T Nohara I Kitagawa 《Chemical & pharmaceutical bulletin》1992,40(11):2990-2994
Three new oleanene glycosides, sophoraflavosides II-IV (2-4) were isolated together with sophoraflavoside I (1) as the corresponding methyl ester forms from Sophorae Radix, the fresh roots of Sophora flavescens AITON (Leguminosae). Their structures have been elucidated as oxytrogenin 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->2)-beta -D- glucuronopyranoside (2), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->2)-beta -D-glucuronopyranosyl oxytrogenin 22-O-alpha-L-arabinopyranoside (3) and 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->2)-beta -D-glucuronopyranosyl oxytrogenin 22-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranoside (4), along with unambiguous characterization as 3 beta,22 beta,24-trihydroxyolean-12-en-29-oic acid for their sapogenol, named oxytrogenin (5) on the bases of chemical reactions and spectral analyses. 相似文献
6.
S. M. Abdur Razzak Yoshinori Namihira Kazuya Miyagi Feroza Begum Shubi Kaijage Nguyen Hoang Hai Tatsuya Kinjo Nianyu Zou 《Optical Review》2007,14(1):14-16
This paper presents a novel technique for the control of chromatic dispersion and confinement loss in hexagonal photonic crystal
fibers (H-PCFs). It is demonstrated that it is possible to obtain very low chromatic dispersion of 0 ± 0:38 ps/(nm·km) in
the wavelength range of 1.41 to 1.66 μm and confinement loss of less than 0.0001 dB/km from a six ring modified H-PCF (MH-PCF).
The higher order dispersion at 1.55 μm is about −0.001 ps/(nm2-km). 相似文献
7.
Ohyanagi T Nagahori N Shimawaki K Hinou H Yamashita T Sasaki A Jin T Iwanaga T Kinjo M Nishimura S 《Journal of the American Chemical Society》2011,133(32):12507-12517
Glycans are expected to be one of the potential signal molecules for controlling drug targeting/delivery or long-term circulation of biopharmaceuticals. However, the effect of the carbohydrates of artificially glycosylated derivatives on in vivo dynamic distribution profiles after intravenous injection of model animals remains unclear due to the lack of standardized methodology and a suitable platform. We report herein an efficient and versatile method for the preparation of multifunctional quantum dots (QDs) displaying common synthetic glycosides with excellent solubility and long-term stability in aqueous solution without loss of quantum yields. Combined use of an aminooxy-terminated thiol derivative, 11,11'-dithio bis[undec-11-yl 12-(aminooxyacetyl)amino hexa(ethyleneglycol)], and a phosphorylcholine derivative, 11-mercaptoundecylphosphorylcholine, provided QDs with novel functions for the chemical ligation of ketone-functionalized compounds and the prevention of nonspecific protein adsorption concurrently. In vivo near-infrared (NIR) fluorescence imaging of phosphorylcholine self-assembled monolayer (SAM)-coated QDs displaying various simple sugars (glyco-PC-QDs) after administration into the tail vein of the mouse revealed that distinct long-term delocalization over 2 h can be achieved in cases of QDs modified with α-sialic acid residue (Neu5Ac-PC-QDs) and control PC-QDs, while QDs bearing other common sugars, such as α-glucose (Glc-PC-QDs), α-mannose (Man-PC-QDs), α-fucose (Fuc-PC-QDs), lactose (Lac-PC-QDs), β-glucuronic acid (GlcA-PC-QDs), N-acetyl-β-D-glucosamine (GlcNAc-PC-QDs), and N-acetyl-β-D-galactosamine (GalNAc-PC-QDs) residues, accumulated rapidly (5-10 min) in the liver. Sequential enzymatic modifications of GlcNAc-PC-QDs gave Galβ1,4GlcNAc-PC-QDs (LacNAc-PC-QDs), Galβ1,4(Fucα1,3)GlcNAc-PC-QDs (Le(x)-PC-QDs), Neu5Acα2,3Galβ1,4GlcNAc-PC-QDs (sialyl LacNAc-PC-QDs), and Neu5Acα2,3Galβ1,4(Fucα1,3)GlcNAc-PC-QDs (sialyl Le(x)-PC-QDs) in quantitative yield as monitored by direct matrix-assisted laser desorption ionization time-of-flight mass spectrometry analyses. Live animal imaging uncovered for the first time that Le(x)-PC-QDs also distributed rapidly in the liver after intravenous injection and almost quenched over 1 h in similar profiles to those of LacNAc-PC-QDs and Lac-PC-QDs. On the other hand, sialyl LacNAc-PC-QDs and sialyl Le(x)-PC-QDs were still retained stably in the whole body after 2 h, while they showed significantly different in vivo dynamics in the tissue distribution, suggesting that structure/sequence of the neighboring sugar residues in the individual sialyl oligosaccharides might influence the final organ-specific distribution. The present results clearly visualize the evidence of an essential role of the terminal sialic acid residue(s) for achieving prolonged in vivo lifetime and biodistribution of various glyco-PC-QDs as a novel class of functional platforms for nanomaterial-based drug targeting/delivery. A standardized protocol using multifunctional PC-QDs should facilitate live animal imaging of ligand-displayed QDs using versatile NIR fluorescence photometry without influence of size-dependent accumulation/excretion pathway for nanoparticles (e.g., viruses) >10 nm in hydrodynamic diameter by the liver. 相似文献
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9.
Tatsuya Kinjo Yoshinori Namihira Kazuya Arakaki Shubi F. Kaijage S. M. Abdur Razzak Feroza Begum Hiroki Higa Shinya Nozaki Nianyu Zou 《Optical Review》2010,17(2):66-73
In this paper we present the design of a modified hexagonal photonic crystal fiber (PCF) having high birefringence and a near-zero
flattened dispersion. Using the finite-difference method (FDM), it is shown that the proposed multiple Gedoped core hexagonal
PCF exhibits a high birefringence of order 10−3 and a nearly zero flattened dispersion in the optical coherence tomography (OCT) waveband. In addition, the proposed PCF
has a confinement loss of less than 10−8 dB/m at 1.06 μm. PCFs with such properties are considered suitable for both endoscopic OCT and other experimental setups
employing 1.06 μm lasers. 相似文献
10.
Bin Rao Prof. Dr. Rei Kinjo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(8):3171-3174
Boragermene 3 featuring a double bond between the Ge and dicoordinate B atoms has been synthesized for the first time by reacting the cyclic (alkyl)(boryl)germylene–PMe3 adduct 1 with Cl2BN(SiMe3)2 followed by reductive dehalogenation with KC8. Addition of a Lewis base (MeNHC) to 3 leads to the formation of the corresponding adduct 4 , which shows double bond character between the Ge and tricoordinate B atoms. Compound 3 undergoes hydrogenation with H2 concomitant with a complete scission of the Ge=B bond. 相似文献