Synthesis of (+)-(S)-Streptenol A and Biomimetic Synthesis of (2R,4S)- and (2S,4S)-2-(Pent-3-enyl)piperidin-4-ol
摘要:
(+)-(S)-Streptenol A 是通过将 1,3-二硫杂烯与光学纯的环氧化物偶联来合成的。因此,(+)-(S)-streptenol A 的绝对构型与 (S)-苹果酸的构型相关联。从 streptenol A 出发,可以方便地制备出一个肟,并通过对其立体选择性地还原,得到了 (3S,5R)-和 (3S,5S)-氨基streptenol。经过环化后,进一步获得了构型纯的 2,4-官能化哌啶生物碱。
Catalytic Enantioselective Epoxidation of Homoallylic Alcohols by Chiral Zirconium Complexes
摘要:
Catalytic enantioselective epoxidation of homoallylic alcohols using Zr(Ot-Bu)(4) and tartrate ester (or tartramide) has been developed. In the Zr(Ot-Bu)(4)/diisopropyl tartrate-catalyzed epoxidation, the reverse of the enantiofacial preference was observed, depending on the Zr/ligand ratios of 1:1 or 1:2.