The absolute stereostructures of betavulgaroside II having a dioxolane-type substituent and betavulgaroside IV having an acetal-type substituent, which were isolated from the roots of Beta vulgaris L. (sugar beet, Chenopodiaceae) and exhibited hypoglycemic activity on glucose-loaded rats, were determined by the chemical correlations of betavulgarosides II and IV with a known saponin, momordin I. In these chemical correlations, the α-L-arabinopyranosyl moiety of momordin I was converted to a dioxolane-type substituent of betavulgaroside II or to an acetal-type substituent of betavulgaroside IV. Additionally, the 2'-diastereoisomer of betavulgaroside IV was synthesized from momordin I, and four acetal-type substituent analogues were also synthesized from L- and D-arabinose.
通过将已知
皂苷 momordin I 与 betavulgaroside II 和 IV 进行
化学关联,确定了从甜菜(藜科)根部分离出的具有对
葡萄糖负荷大鼠的降血糖活性的含有
二氧六环型取代基的 betavulgaroside II 和含有
缩酮型取代基的 betavulgaroside IV 的绝对立体结构。在这些
化学关联中,momordin I 的 α-
L-阿拉伯糖苷部分被转化为 betavulgaroside II 的
二氧六环型取代基或 betavulgaroside IV 的
缩酮型取代基。此外,从 momordin I 合成了 betavulgaroside IV 的 2'-非对映异构体,并从 L- 和
D-阿拉伯糖合成了四种
缩酮型取代基类似物。