防已科植物アルカロイド研究 (第200報)
TrilobineおよびIsotrilobineの構造 その15 EpistephanineよりIsotrilobine Antipodeの合成
1963 年 83 巻 7 号 p. 676-679
詳細
1963 年 83 巻 7 号 p. 676-679
Y. Inubushi and K. Nomura reported a ring cleavage reaction of natural isotrilobine with sodium in liquid ammonia and represented its structure by II. In the present paper authors showed that the demethylation and dehydration of N-methyldihydroepistephanine (V) with hydrobromic acid followed by O-methylation gave O-methylanhydrodemethyl-N-methyldihydroepistephanine (VIII) (picrate, m. p. 188-189° (decomp.), [α]D -226.7° (acetone)), which is the antipode of natural isotrilobine (cf. Table I).
