作者:Dawei Ma、Wei Zhu
DOI:10.1016/j.tetlet.2003.09.149
日期:2003.11
Condensation of protected δ-hydroxy-β-amino ester 7 with a β-keto ester provides vinylogous urethane 8, which is cyclized under the action of t-BuOK followed by decarboxylation to afford enone 12. Hydrogenation of 12 or its N,O-diprotected derivative 13 gives 2,6-cis-disubstituted piperdines. Using these intermediates, (−)-8-epi-hyperaspine is synthesized.
受保护的δ-羟基-β-氨基酯7与β-酮酸酯的缩合可提供乙烯基氨基甲酸酯8,该氨基甲酸酯在t- BuOK的作用下环化,然后脱羧得到烯酮12。的氢化12或其ñ,ö -diprotected衍生物13给出了2,6-顺式二取代的piperdines。使用这些中间体,合成了(-)-8-表位-高肾上腺素。