共查询到10条相似文献,搜索用时 156 毫秒
1.
P. I. Abronina L. V. Backinowsky A. A. Grachev S. L. Sedinkin N. N. Malysheva 《Russian Chemical Bulletin》2005,54(5):1287-1293
Methyl 2,4-di-O-benzoyl-α-D-mannopyranoside was used as a key intermediate in the synthesis of 3,6-branched mannopentaoside bearing one terminal D-[1-13C]mannopyranose residue, viz., methyl 6-O-[3,6-di-O-(α-D-mannopyranosyl)-α-D-mannopyranosyl)-3-O-{α -D-[1-13C]mannopyranosyl}-α-D-mannopyranoside.
Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday.
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Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1250–1255, May, 2005. 相似文献
2.
N. A. Ivanova Z. R. Valiullina O. V. Shitikova M. S. Miftakhov 《Russian Chemical Bulletin》2005,54(11):2698-2701
The reaction of methyl 3,6-anhydro-2,7-dideoxy-7-iodo-4,5-O-isopropylidene-D-allo-heptonate with 1,8-diazabicyclo[5.4.0]undec-7-ene affords methyl 3,6-anhydro-2,7-dideoxy-4,5-O-isopropylidene-D-ribo-hept-6-enonate, which undergoes the previously unknown rearrangement into a 2,2-dimethyl-1,3-dioxole derivative.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2610–2613, November, 2005. 相似文献
3.
Barbagallo RN Spagna G Abbate C Azzaro G Palmeri R 《Applied biochemistry and biotechnology》2002,101(1):1-13
β-d-Glucopyranosidase (βG, EC 3.2.1.21) has been isolated from some collateral activities, α-l-arabinofuranosidase (Ara, EC3.2.1.55), α-l-rhamnopyranosidase (Rha, EC 3.2.1.40), and o-acetylesterase (Est, EC 3.1.1.53), using a commercial enzyme preparation and a simple method economically sustainable for
the food industry. The procedure comprises precipitation of extraneous substances by adding ethanol and CaCl2, ultrafiltration, and adsorption, first on bentonite and then on chitosan. The results obtained were the complete isolation
of βG from the above-mentioned activities, a drastic reduction in extraneous compounds, such as brown substances and polysaccharides,
and a slight increase in purification. 相似文献
4.
O. B. Flekhter L. A. Baltina L. V. Spirikhin I. P. Baikova G. A. Tolstikov 《Russian Chemical Bulletin》1998,47(3):513-516
Betulin 2-deoxy-α-d-, 2-deoxy-α-l-, and 2,6-dideoxy-α-l-arabino-hexopyranosides were synthesized by acid-catalyzed glycosylation (cationite in the H+ form, LiBr) of betulin 3- and 28-monoacetates with glycal acetates.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 531–534, March, 1998. 相似文献
5.
Yodthong Baimark Mangkorn Srisa-ard Jirasak Threeprom Nual-Anong Narkkong 《Colloid and polymer science》2007,285(13):1521-1525
Nanoparticle colloids of methoxy poly(ethylene glycol)-b-poly(D,L-lactide) (MPEG-b-PDLL) diblock copolymer were prepared by a modified spontaneous emulsification solvent diffusion method using acetone/ethanol
as the mixture organic solvents. The MPEG-b-PDLL was synthesized by ring-opening polymerization of D,L-lactide using stannous octoate and MPEG with molecular weight of 5,000 g/mol as the initiating system. The MPEG-b-PDLL obtained was an amorphous polymer with molecular weight of 73,600 g/mol. Influences of acetone/ethanol (v/v) ratios
and Tween 80 surfactant concentrations on characteristics of the colloidal nanoparticles were investigated and discussed.
Light-scattering analysis showed that average diameters of the surfactant-free colloidal nanoparticles were in the range of
86–124 nm. The nanoparticle sizes decreased as the ethanol ratio increased. The Tween 80 did not show the significant effect
on the nanoparticle sizes. Scanning electron micrographs of dried nanoparticles that demonstrated the aggregation of most
particles suggested they were the soft nanoparticles. However, the dried nanoparticle morphology can be observed from scanning
electron microscopy as having a spherical shape and smooth surfaces. 相似文献
6.
L. A. Baltina O. B. Flekhter E. V. Vasil'eva G. A. Tolstikov 《Russian Chemical Bulletin》1997,46(3):577-581
2-Deoxy-α-d-lyxo-hexopyranosides of 18β-glycyrrhetic acid, its 11-deoxo derivative and allobetulin were synthesized by glycosylation of oleonane-type
triterpene alcohols withd-galactal acetate in the presence ofN-iodosuccinimide followed by deiodination and deprotection.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 596–600. March, 1997. 相似文献
7.
The fluorescence of fluoresceinisothiocyanate-labeled concanavalin A (FITC-Con A) was quenched by forming an FITC-Con A–glycogen
conjugate and dequenched upon addition of sugars to the conjugate solution due to disaggregation of the conjugate. However,
fluorescence quenching was barely observed upon formation of FITC-Con A–dextran conjugate. The sugar-induced fluorescence
response of the FITC-Con A–glycogen conjugate depended significantly on the type of sugar: methylated α-D-glucose and α-D-mannose both induced high and rapid responses, while the responses to D-mannose and D-glucose were moderate. In contrast, no response was observed in the presence of D-galactose due to a lack of affinity to Con A. Thus, it is apparent that D-glucose and other sugars can be detected via the fluorescence of the FITC-Con A–glycogen conjugate.
相似文献
8.
Etoh S Hamase K Morikawa A Ohgusu T Zaitsu K 《Analytical and bioanalytical chemistry》2009,393(1):217-223
The cellular localization of D-alanine (D-Ala) in the rat pituitary gland, the tissue containing the highest amount of D-Ala, has been clarified for the first time by enantioselective visualization of D-Ala using our own established mouse monoclonal antibody against D-Ala. D-Ala immunopositive cells were present predominantly in the anterior lobe, while no intense staining was observed in the intermediate
and posterior lobes. The anterior pituitary gland contains five types of cells secreting specific hormones (growth hormone,
adrenocorticotropic hormone (ACTH), gonadotropic hormone, prolactin, and thyroid-stimulating hormone), and the double staining
results indicated that D-Ala is localized to the ACTH-secreting cells. The localization of D-Ala is clearly different from that of D-aspartic acid (D-Asp), which is observed in the prolactin cells. Considered together with our previous findings that D-Ala is localized to the insulin-secreting beta-cells in the pancreas, and both ACTH and insulin are typical regulatory hormones
of blood glucose, D-Ala is suggested to have some functional relationships to blood glucose level regulation in mammals. 相似文献
9.
A. Yu. Spivak O. V. Knyshenko O. V. Ivanova M. I. Mallyabaeva E. S. Murtazina I. Yu. Ponedel’kina V. N. Odinokov 《Russian Chemical Bulletin》2007,56(12):2487-2490
The use of a combination of ionic liquid [bmim]PF6 with boron trifluoride etherate as the catalyst in the glycosylation of α-tocopherol and chromanol of vitamin K1 (naphthotocopherol) allowed us to obtain β-glycosides in high yield when β-anomer of peracetylated D-glucose was used. In addition, usually inactive α-anomers of peracetylated D-glucopyranose and D-galactopyranose were involved in this reaction.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2401–2404, December, 2007. 相似文献
10.
L. T. Eremenko G. V. Oreshko G. V. Lagodzinskaya G. G. Aleksandrov I. L. Eremenko 《Russian Chemical Bulletin》2007,56(10):2097-2104
The reaction of 1,4:3,6-dianhydro-D-sorbitol 5-nitrate with POCl3 afforded mono-and bis(5-O-nitro-1,4:3,6-dianhydro-D-sorbit-2-yl) phosphorochloridates, whose hydrolysis resulted in phosphoric acid mono-and diesters. The subsequent treatment
of these compounds with bases gave sodium and cyclohexylammonium salts. The reactions of phosphorochloridates with phenol,
pentaerythritol dibromohydrin, and ethylenimine in the presence of organic bases afford mixed phosphates and phosphoramidates.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2026–2032, October, 2007. 相似文献