A naphthalene glucoside lactone from Rhamnus wightii
摘要:
A new naphthalene glucoside lactone was isolated from the acetone extract of the stem bark of Rhamnus wightii. Cynodontin, chrysophanol, physcion, musizin, lupeol, sitosterol, 7-hydroxy-5-methoxyphthalide, emodin, sitosterol glycoside, beta-sorigenin are the known compounds; beta-sorigenin may be an artifact of its glucoside. The co-occurrence of two lactone ring compounds, 7-hydroxy-5-methoxyphthalide and the naphthalide glucoside is the significant feature of this plant.
Transpositive Tandem Annulation of Phthalides with Allene Carboxylates: Regioselective Synthesis of Arylnaphthalene Lignans
作者:Dipakranjan Mal、Supriti Jana
DOI:10.1021/acs.joc.6b02313
日期:2016.12.2
Allene carboxylates, scarcely used as Michael acceptors, serve as acceptors in the annulation with phthalides in the presence of LDA and provide a one-pot synthesis of naphtho[c]furanones in very good yields. This tandem annulation is proposed to proceed via transposition of the hydroxy group resulting from the initial annulation.
几乎不用作迈克尔受体的丙二烯羧酸盐在LDA存在下与邻苯二甲酸酯成环时用作受体,并以非常高的收率提供一锅法合成萘并[ c ]呋喃酮。提出这种串联环化是通过由初始环化产生的羟基的转位进行的。
Nikuni; Hitsumoto, Nippon Nogeikagaku Kaishi, 1944, vol. 20, p. 283,286