synthetic study of dihydroxyanonens, neurotrophic effect increasing natural products

点击翻译按钮获取中文摘要

Diihydroxyanones attract many researchers as lead compounds for the development of anti-Alzheimer's disease or the learning improvement drugs due to the increasing effect to the activity of neurotrophins. In this study, we achieved the construction of tetraalkyl chiral quaternary carbon center utilizing diastereoselective 1,4-addition of divinylcuplate to the unsaturated carboxylic acid consisting chiral oxazolidinone as a chiral auxiliary in high diastereoselectivity. Subsequently, the 1,4-adduct was reacted with iodomethane after the treated with SHMDS, converted to alfa-alkylated compound with high diastereoselectivity. These reactions allowed to induce chiralities at C8,9 of dihydroxyanones. The removal of oxazolidinone was hard. The usual basic condition, hydroxyperoxide with alkaline or reduction did not proceed. Eventually, we found that LiAlH4 reduction after the substitution with sodium ethylthiolate give the corresponding alcohol in high yield.