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二苯羟乙酸衍生物及糖类化合物分别具有重要的生理功能.二苯羟乙酸糖酯有可能同样具有一定的生理价值.本文着重对这类化合物的酶促合成进行探讨,选择定位合成二苯羟乙酸糖酯. 相似文献
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核苷类化合物酯类衍生物在功能高分子材料、寡聚核苷酸和医药化学等领域具有重要的应用价值。本文就近年来核苷类化合物酯类衍生物酶法合成的研究进行综述。 相似文献
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Advances in heterocyclic ketene aminals 总被引:1,自引:0,他引:1
Recent developments in the study of the reactions of heterocyclic ketene aminals are reviewed with the emphases on regioselective alkylation, acylation and glycosylation reactions, and on the aza-ene reactions with α,β-unsaturated compounds, azo and carbonyl compounds. Reactions with 1,3-dipoles and other reagents to synthesize fused heterocycles are also discussed. 相似文献
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A series of 2-nitro-5, 10, 15, 20-tetra (4-methoxyphenyl) porphyrinato metals were regioselectively synthesized with nitrate
salts as nitrating reagent in acetic acid/acetic anhydride for preparation of 2-substituted porphyrin. The influence of nitrate
salts and complex metal ion to the reaction were investigated. The extent of 2-nitration increased with the electronegativity
of the central metal. When Cu(NO3)2×3H2O was used as nitrating reagent, almost quantitative yields of 2-nitro porphyrin were obtained in the case of Cu (II) or Ni
(II) chelates, while Zn(II) or Mn(II) chelates gave 50% and 30% yields respectively. If Zn(NO3)2×10H2O was used as nitrating agent, no product was found for Cu(II) or Ni(II) chelates, 12% was found for Zn(II) chelates. The
other metal ion and nitrate salts were also found in quite different influence.
Foundation item: Supported by the National Natural Science Foundation of China (29872033)
Biography: Chen Zhang-ping (1946-), male, Professor, research direction, porphyrin. 相似文献
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A series of 2-nitro-5,10,15,20-tetra(4-methoxyphenyl) porphyrinato metals were regioselectively synthesized with nitrate salts as nitrating reagent in acetic acid/acetic anhydride for preparation of 2-substituted porphyrin. The influence of nitrate salts and complex metal ion to the reaction were investigated. The extent of 2-nitration increased with the electronegativity of the central metal. When Cu(NO3)2·3H2O was used as nitrating reagent, almost quantitative yields of 2 nitro porphyrin were obtained in the case of Cu(Ⅱ) or Ni(Ⅱ) chelates, while Zn(Ⅱ) or Mn(Ⅲ) chelates gave 50% and 30% yields respectively. If Zn(NO3)2·10H2O was used as nitrating agent, no product was found for Cu(Ⅱ) or Ni(Ⅱ) chelates, 12% was found for Zn(Ⅱ) chelates. The other metal ion and nitrate salts were also found in quite different influence. 相似文献
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Takeshi Sugai 《复旦学报(自然科学版)》2005,44(5):794-795
Preparation of rare aminosugars such as N-acetylgalactosamine (GalNAc) in large quantities is of importance for the chemo-enzymatic synthesis of oligosaccharides. Starting from naturally abundant N-acetylglucosarnine (GIcNAc), the regio-and stereoselective and new functional group transformation play important roles as the key reactions. 相似文献
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