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411.
The addition of 2-lithiobenzothiazole to d-gluconolactone followed by deoxygenation of the resulting ketose affords a mixture of benzothiazolyl α- and β-d-glucopyranoside; treatment of this mixture with sodium methoxide gives the β-anomer from which the title aldehyde is obtained in a pure form by transformation of the benzothiazole ring into the formyl group. 相似文献
412.
413.
蜂蜜中糖的薄层展开剂的研究与应用 总被引:4,自引:0,他引:4
建立了蜂蜜中糖的薄层色谱分析法。色谱条件:冰醋酸-氯仿-95%乙醇(体积比为21∶23∶15)为流动相,固定相为涂布于薄层板上的硅胶G-0.2 mol/L 醋酸钠溶液。对多个蜂蜜样品和果糖、葡萄糖、蔗糖标准品进行上行展开,并用苯胺-二苯胺-磷酸显色剂显色。结果表明:真蜜图谱上出现5个色斑,其中果糖呈火红色,葡萄糖呈纯蓝色,蔗糖呈紫色,麦芽糖和多聚葡萄糖呈蓝色。将样品色斑的颜色、深浅度和Rf值与标准糖进行比较,能判断蜂蜜中的还原糖总含量和蔗糖含量,同时也能了解其他少量多糖的存在情况。通过与真蜜图谱比较, 相似文献
414.
毛细管电泳—激光诱导荧光—增强型电荷耦合器件检测痕量氨基糖 总被引:3,自引:0,他引:3
利用毛细管电泳-激光诱导荧光-增强型电荷耦合器件系统,高灵敏度检测了痕量氨基糖。以异硫氰酸荧光素为荧光衍生试剂,氨基葡萄糖,氨基半乳糖及氨基葡萄酸为模型化合物,具体考察了缓冲溶液,PH值等多种因素对荧光衍生反应和电泳分离的影响。 相似文献
415.
Li Zhong Shu Wenli Liao Yongzhong Huang Peiquan Xu Qingcai 《Chinese Journal of Reactive Polymers》1996,(Z1)
DETERMINATIONOFTHERMODYNAMICANDKINETICPARAMETERSOFLARGESCALECHROMATOGRAPHICSEPARATIONOFSUGARANDREDUCINGSUGARLiZhong;ShuWenli;... 相似文献
416.
Mitsuji Yamashita Valluru Krishna ReddyPutta Mallikarjuna Reddy Yukihiro KatoBuchammagari Haritha Kazumitsu SuzukiMasaki Takahashi Tatsuo Oshikawa 《Tetrahedron letters》2003,44(17):3455-3458
An efficient method is described in the synthesis of several novel deoxy phospha sugar pyrimidine nucleosides in racemic form, analogs of normal sugar nucleosides, in high yields by treatment of (±)-2-aminophospholane 1-oxide with several, α-cyano-, -acetyl-, -ethoxycarbonyl-β-ethoxy-N-ethoxycarbonylacrylamides. 相似文献
417.
Three designed arabinofuranose building blocks allowed the diastereoselective synthesis of a C-disaccharide and a C-trisaccharide by Wittig olefination. The latter compound represents the first example of all-carbon linked arabinofuranotriose analogue. 相似文献
418.
Mothé C. G. de Araujo C. R. de Oliveira M. A. Yoshida M. I. 《Journal of Thermal Analysis and Calorimetry》2002,67(2):305-312
Polyurethane composites with bagasse of sugar cane (BSC) at different proportions: 5, 10 and 20 mass/mass% were prepared by
melt mixing method. The thermal behavior of these composites were studied by thermogravimetry (TG/DTG). The influence of fiber
concentration on the kinetic parameters of the composites was studied and a better interaction was suggested between PU/BSC
with 5mass/mass% of fiber. Scanning electron microscopy was carried out to investigate surface morphology.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
419.
Cynthia B. Myers Mercy M. Ramanjulu H. L. Carrell Jenny P. Glusker 《Structural chemistry》1997,8(1):65-71
The synthesis of a novel compound, 3-deoxy-3-fluoro--d-allopyranoside, is described. It involves blocking the 4- and 6-positions of allose to cause fluorination only at the 3-position. This six-step synthesis gave pure crystalline compound in a 5% overall yield. The crystal structure, determined by X-ray diffraction, confirmed the chemical formula and configuration of the product. It showed that the C-F bond isaxial, while the C-(OH) bonds areequatorial. The overall conformation of this fluoroallose is similar to that of allose (Acta Cryst.1984,C40, 1863) (with OH instead of F), but the packing in the two crystals is different in the region of C3, the site of chemical variation. 相似文献
420.
Nitrone 3 analogue of 5-deoxy-l-lyxose was derived from d-ribose. Its reduction with aqueous SO2 gave the corresponding 4-amino-sugar 2, a potent α-l-fucosidase inhibitor. 1,3-Dipolar cycloaddition of 3 with alkenes allowed the synthesis of acetohydroxamic acid and ethane-phosphonate derivatives. Hydroxy-ethane derivative 15 is a nanomolar α-l-fucosidase inhibitor. 相似文献