P-10 触媒的環化アルケニル化反応を利用する炭素20ジベレリン類の不斉全合成(ポスター発表の部)

概要

論文の詳細を見る
The gibberellins are devided into two groups, the larger of which is C_<19> gibberellins [gibberellic acid: GA3; a typical representative], with most of the remaining have 20 carbons. The latter possesses entgibberellane framework. GA_<112> belongs to C_<20> gibberellins, and GA_<12> is believed to be a common intermediate in the biosynthesis of all gibberellins. Since the question of how to establish practical routes for the construction of C_<20> gibberellins was open, we made a start in the study of a stereoselective synthesis of GA_<112> employing the palladium-catalyzed cycloalkenylation developed by us. As a result, a highly stereoselective total synthesis of chiral GA_<112> was achieved by a combination of palladium-catalyzed cycloalkenylation and reverse electron demand intramolecular Diels-Alder reaction. The most important aspect of the present synthesis is that all stereoisomers produced were used, and most of the reaction yields are good. The present synthesis. would provide some perspectives both on the determination of tentative new structures and on the exploration of their bioactivities.
天然有機化合物討論会の論文
2007-08-24