环糊精(CD)是由若干葡萄糖残基以α-(1,4)-糖苷键连接而成的大环化合物,它最大的特征是能在其分子空腔内结合多种有机、无机分子,因此 CD 及经化学修饰得到的一些衍生物可以较好地模拟天然酶的一些特性。对 CD 进行化学修饰的一个重要...环糊精(CD)是由若干葡萄糖残基以α-(1,4)-糖苷键连接而成的大环化合物,它最大的特征是能在其分子空腔内结合多种有机、无机分子,因此 CD 及经化学修饰得到的一些衍生物可以较好地模拟天然酶的一些特性。对 CD 进行化学修饰的一个重要步骤往往是对它的羟基进行选择性的磺酰化。β-CD 是由7个葡萄糖残基组成的。展开更多
Silver(Ⅰ) oxide was applied to the selective p-tosylation of hydroxyls of saccharide. The reaction of p-methylphenyl-4,6-O-benzylidene-1-thio-β-D-glucopyranoside(A) with a stoichiometric amount of p-toluenesulfo...Silver(Ⅰ) oxide was applied to the selective p-tosylation of hydroxyls of saccharide. The reaction of p-methylphenyl-4,6-O-benzylidene-1-thio-β-D-glucopyranoside(A) with a stoichiometric amount of p-toluenesulfonyl chloride(TsCl) in the presence of silver(Ⅰ) oxide and a catalytic amount of potassium iodide selectively led to the monotosylate derivative:p-methylphenyl 3-O-p-toluenesulfonyl-4,6-O-benzylidene-1-thio-β-D-glucopyranoside(B) in a high yield(97%). A possible mechanism of the reaction is proposed. The rational reaction process is that at n(TsCl)∶n(Ag2O)∶n(A)∶n(KI)=1.2∶1.5∶1.0∶0.2, the mixture is stirred at room temperature for 8 h, 2.74 g(97%)B could be isolated from 2.0 g of compound A.展开更多
文摘环糊精(CD)是由若干葡萄糖残基以α-(1,4)-糖苷键连接而成的大环化合物,它最大的特征是能在其分子空腔内结合多种有机、无机分子,因此 CD 及经化学修饰得到的一些衍生物可以较好地模拟天然酶的一些特性。对 CD 进行化学修饰的一个重要步骤往往是对它的羟基进行选择性的磺酰化。β-CD 是由7个葡萄糖残基组成的。
文摘Silver(Ⅰ) oxide was applied to the selective p-tosylation of hydroxyls of saccharide. The reaction of p-methylphenyl-4,6-O-benzylidene-1-thio-β-D-glucopyranoside(A) with a stoichiometric amount of p-toluenesulfonyl chloride(TsCl) in the presence of silver(Ⅰ) oxide and a catalytic amount of potassium iodide selectively led to the monotosylate derivative:p-methylphenyl 3-O-p-toluenesulfonyl-4,6-O-benzylidene-1-thio-β-D-glucopyranoside(B) in a high yield(97%). A possible mechanism of the reaction is proposed. The rational reaction process is that at n(TsCl)∶n(Ag2O)∶n(A)∶n(KI)=1.2∶1.5∶1.0∶0.2, the mixture is stirred at room temperature for 8 h, 2.74 g(97%)B could be isolated from 2.0 g of compound A.