when different protecting groups of Nb are utilized. This dimerization reaction could be conducted in gram scale. With this dimerization method, both endocyclotryptophan (+)-WIN 64821 and exocyclotryptophan (−)-ditryptophenaline were synthesized in 5 steps.
铜介导的
色胺或色
氨酸的环化和二聚化一步一步就产生了具有两个连续的立体生季碳的C 2对称C 3(sp 3)–C 3(sp 3)桥。令人印象深刻的是,当使用不同的Nb保护基时,外环和内环化产物之间的比率会发生变化。该二聚反应可以以克为单位进行。通过这种二聚化方法,以5个步骤合成了内环色
氨酸(+)-WIN 64821和外环色
氨酸(-)-二苯甲
酚。