The second reaction we tested was diastereoselective Michael-Aldol annulation of B-keto ester 121 with methacrolein to give a key intermediate for synthesizing (-)-Huperzine A.

• 其次，我们以手性胍为催化剂，探索了带有手性辅基的B-酮酯121g、121h和121i与异丁烯醛的不对称Michael/Aldol串联反应，不对称地合成天然石杉碱甲((-)-Huperzine A)的关键中间体123。