Efforts to total synthesis of philinopside E: convergent synthesis of the sulfated lanostane-type tetraglycoside
作者:Shujin Bai、Zhiyong Wu、Qingyun Huang、Li Zhang、Pengwei Chen、Cong Wang、Xiuli Zhang、Peng Wang、Ming Li
DOI:10.1039/c5ra25845f
日期:——
As an important step to total synthesis of philinopside E with important antitumor activities (Ed50 0.75–3.50 μg mL−1), we described herein convergent synthesis of a triterpene glycoside composed of the sulfated tetrasaccharide residue identical to that of philinopside E and the aglycone of lanost-7-en-3β-ol. The stereocontrolled synthesis of the aglycone from 24,25-dihydrolanosterol was accomplished
作为具有重要抗肿瘤活性(Ed 50 0.75–3.50μgmL -1)的菲洛甙E的全合成的重要步骤,我们在本文中介绍了由硫酸化四糖残基组成的三萜糖甙的聚合合成,该残基与菲洛甙E和糖苷配基相同lanost-7-en-3β-ol。依靠24,25-二氢羊毛甾醇的立体控制合成糖苷配基是依靠2,3-不饱和-1,4-二酮体系的立体选择性还原,并借助C3-叔丁基二甲基甲硅烷氧基进行的,并且方便地安装了所需的7( 8)-通过syn的双键消除三氟甲磺酸。通过使糖苷配基与正交保护的木糖基硫糖苷与源自葡萄糖,木糖和喹诺糖衍生物的三糖硫糖苷反应制备的单糖苷顺序收敛会聚,并结合硫酸化和脱保护得到目标分子。我们工作的特点是立体选择性地构建了四个1,2-反式糖苷键,并在后期合成过程中引入了珍贵的糖苷配基,这将促进总酚蓝甙E及其相关天然产物的合成。