No-硝基苯基-2,3,4,6-四-O-乙酰基-β-D-吡喃葡萄糖胺(1),Nm-硝基苯基-2,3,4,6-四-O-的X射线衍射分析进行了乙酰基-β-D-吡喃葡萄糖胺,Np-硝基苯基-2,3,4,6-四-O-乙酰基-β-D-吡喃葡糖胺及其N-乙酰基衍生物的制备。糖部分总是采用(4)C1构象,但是,由于晶体堆积力,它们总是会略微变形。结果发现,除N-乙酰基,Nm-硝基苯基-2,3,4,6-四-O-乙酰基-β-D-吡喃葡萄糖胺(5)外,本文研究的吡喃葡萄糖胺均未在其中形成强氢键。水晶格子。另外,(5)与水分子一起结晶,该水分子占据特殊的晶体学位置(在双向轴上),并通过氢键连接两个糖分子。CP MAS NMR光谱证实了(5)中涉及水分子的分子间氢键的存在。此外,已证明在(1)中,在糖苷键和硝基之间形成了分子内氢键。
DOI:
10.1016/j.carres.2006.06.021
作为产物:
描述:
mixture of anomers of D-m-nitrophenylglucosylamine tetraacetate 在
sodium methylate 作用下,
以
甲醇 为溶剂,
反应 24.0h,
以18%的产率得到α-D-m-nitrophenylglucosylamine
参考文献:
名称:
Kaletina, N. I.; Bezzubov, A. A.; Stepanenko, B. N., Journal of general chemistry of the USSR, 1981, vol. 51, p. 2408 - 2411
N-(m-Nitrophenyl)-beta-D-glucopyranosylamine (Gln), N-(N-methylphenyl)-beta-D-glucopyranosylamine (Glm), N-beta-D-glucopyranosylpyrazole (Glp), and N-beta-D-glucopyranosylimidazole (Gli) have been synthesized. Their basicity constants, pKb, determined in methanol were, respectively, 14.99, 14.36, 15.04, and 9.74. The derivatives of secondary amines (Glm, Glp, and Gli) did not mutarotate in methanol
GLYCOSYLTRANSFERASE REVERSIBILITY FOR SUGAR NUCLEOTIDE SYNTHESIS AND MICROSCALE SCANNING
申请人:Thorson Jon S.
公开号:US20130004979A1
公开(公告)日:2013-01-03
The present invention generally relates to materials and methods for exploiting glycosyltransferase reversibility for nucleotide diphosphate (NDP) sugar synthesis. The present invention provides engineered glycosyltransferase enzymes characterized by improved reaction reversibility and expanded sugar donor specificity as compared to corresponding non-mutated glycosyltransferase enzymes. Such reagents provide advantageous routes to NDP sugars for subsequent use in a variety of biomedical applications, including enzymatic and chemo-enzymatic glycorandomization.