Bridged bicyclic piperazines are important building blocks in medicinal chemistry research. The bicyclic piperazine 3,6-diazabicylo[3.1.1]heptane is of particular interest as a piperazine isostere because it is achiral and shows similar lipophilicity to that of piperazine based on the c Log P of a derived analog. A concise synthesis of N³- and N⁶-monoprotected 3,6-diazabicyclo[3.1.1]heptanes 2d and 2e, respectively, is described. The seven step sequence begins with inexpensive starting materials and uses straightforward chemistry.

中文翻译：

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N ^3-和N ^6-单保护的3,6-二氮杂双环[3.1.1]庚烷的精确合成；制备新型桥联双环哌嗪的有用中间体

桥接的双环哌嗪是药物化学研究的重要组成部分。双环哌嗪3，6-二氮杂双并[3.1.1]庚烷作为哌嗪等位异构体特别受关注，因为它是非手性的，并且基于衍生类似物的c  Log  P表现出与哌嗪相似的亲脂性。描述了分别由N ^3-和N ^6-单保护的3,6-二氮杂双环[3.1.1]庚烷2d和2e的简明合成。七个步骤的序列从廉价的起始原料开始，并使用简单的化学方法。