Department of Chemistry, Temple University, Philadelphia, PA 19122, USA.
Org Biomol Chem. 2009 Dec 21;7(24):5067-73. doi: 10.1039/b915796d. Epub 2009 Oct 26.
The first total asymmetric synthesis of the poison frog alkaloid (-)-221T, a 5,6,8-trisubstituted indolizidine is described. The key core piperidine ring was constructed via an acid catalyzed intramolecular cascade Mannich cyclization reaction of a N-sulfinyl syn-alpha-methyl beta-amino ketone and crotonaldehyde. The beta-amino ketone was prepared via the reaction of prochiral lithium Weinreb amide enolate with an enantiopure N-2,4,6-triisopropylphenylsulfinyl imine.
描述了毒蛙生物碱（-）-221T 的首次全不对称合成，它是一个 5,6,8-三取代的吲哚里西啶。关键核心哌啶环是通过 N-亚磺酰基顺式-α-甲基-β-氨基酮和巴豆醛的酸催化分子内级联 Mannich 环化反应构建的。β-氨基酮是通过手性前体锂 Weinreb 酰胺烯醇化物与对映体纯的 N-2,4,6-三异丙基苯亚磺酰亚胺的反应制备的。
