リスラニン型ミソハギアルカロイド, (±)-Lythranidineの合成研究

抄録

From a synthetic point of view, total synthesis of (±)-lythranidine, an alkaloid isolated from Lythrum anceps MAKINO, involves the following four interesting problems ; the construction of the 17-membered ring, the formation of trans-2, 6-disubstituted piperidine ring, the settlement of the correct relative stereochemistry of the four asymmetric centers in the mobile macrocyclic ring system, and the construction of unsymmetrically substituted biphenyl moiety. The details how to solve them are discussed. The last problem was rather easily solved by partial demethylation of a 2, 2'-dimethoxybiphenyl derivative with a reagent system including a hard acid and a soft nucleophile. This reagent system has been shown to be effective for the cleavage of a variety of carbonoxygen bonds and some carbon-carbon double bonds. These bond cleavage reactions by a hard acid and soft nucleophile system are shortly reviewed in the latter part of this article.