iminodiacetic anhydride) were converted into cis- and trans-configured bicyclic piperazines containing two stereogenic centers. The latter are not only well-established mimetics of peptide β-turn but also attractive, high-Fsp3 cores for drug design in general. The methodology was applied to the preparation of ring-expanded version of bicyclic piperazines not described in the literature.
5-Oxopiperazine-2-carboxamides和相应的
羧酸(通过受保护的
亚氨基二乙酸酐的Castagnoli-Cushman反应获得)转化为包含两个立体中心的顺式和反式双环
哌嗪。后者不仅是公认的肽β-转角模拟物,而且还是通常用于药物设计的引人注目的高F sp3核心。该方法学被用于制备文献中未描述的双环
哌嗪的环扩展形式。