Conformationally Rigid Tricyclic Tripods: Synthesis and Application to Preparation of Enterobactin Analogs
作者:Bruno Tse、Yoshito Kishi
DOI:10.1021/jo00104a043
日期:1994.12
The syntheses of the conformationally rigid triol 2 and triamine 3 are described. One of the key features of these syntheses was that each of the intermediates involved contained a symmetry element, which made their structure elucidation facile and conclusive. The structural similarity between the platform of enterobactin in its metal binding state and triamine 3 was recognized, and the enterobactin analog 14 was synthesized. The K-f value observed for 14 was as high as the K-f value for enterobactin itself, and higher than the K-f value for any enterobactin analog ever reported. In comparison with a number of synthetic enterobactin analogs, it became evident that the conformational rigidity of the enterobactin platform, resulting in good preorganization of the three catechol moieties toward Fe(III)-chelation, was an important factor contributing to its extraordinarily high K-f.