Systematic Asymmetric Synthesis of All Diastereomers of (−)-Talaumidin and Their Neurotrophic Activity
作者:Kenichi Harada、Miwa Kubo、Hiroki Horiuchi、Akiko Ishii、Tomoyuki Esumi、Hideaki Hioki、Yoshiyasu Fukuyama
DOI:10.1021/acs.joc.5b00945
日期:2015.7.17
result in the presence of seven diastereomers except for their enantiomers. In order to investigate the stereochemistry–activity relationships of the stereoisomers, the systematic synthesis of all stereoisomers of 1 was accomplished by employing Evans aldol, diastereoselective hydroboration, reductive deoxygenation, and Mitsunobu reactions as key steps. The ability of all of the synthesized stereoisomers
(-)-Talaumidin(1),一种从马兜铃大师分离的2,5-联芳基-3,4-二甲基四氢呋喃木脂聚糖,在原代培养的大鼠皮层神经元和NGF分化的PC12细胞中显示出明显的神经突增生和神经保护作用。1中四氢呋喃部分上的四个立体异构中心导致存在七个非对映异构体(对映异构体除外)。为了研究立体异构体的立体化学-活性关系,对1的所有立体异构体进行系统合成通过采用Evans aldol,非对映选择性硼氢化,还原性脱氧和Mitsunobu反应作为关键步骤来完成。评估了所有合成的立体异构体在PC12和神经元细胞中促进神经突生长的能力。在NGF分化的PC12细胞中,所有立体异构体均表现出中度至强效的神经营养活性,浓度为30μM,在原代培养的大鼠皮质神经元细胞中,其浓度为0.01μM。特别地,带有所有顺式取代基的1e导致最有效的神经突增生。