In addition to two known ecdysteroids, 20-hydroxyecdysone and turkesterone, three previously undescribed stigmastane-type ecdysteroids were isolated from the underground parts of Rhaponticum acaule (L.) DC. by chromatographic techniques (CC, VLC, MPLC). The structures of the compounds were established by chemical (acetylation) and spectroscopic methods including UV, IR, HRMS, 1D-NMR: 1H-NMR, 13C-NMR, DEPT-135. and 2D-NMR: COSY, NOESY, HSQC, HMBC. Two compounds were isolated as an isomeric mixture and each of them was purified and converted to the corresponding acetylated derivative. Based on all of the evidence, the structures of three undescribed stigmastane-type ecdysteroids were established as 2β,3β,11α,20β,22α,24,28-heptahydroxy-6-oxo-stigmast-7-en-25,29-lactone and the cyclic 22,29-hemiacetals 22R and 22S stigmast-7-en-29-al,2β,3β,11α,20α,22,28-hexahydroxy-6-oxo, and the trivial names acaulesterone and rhapocasterones A and B are suggested, respectively. The structures and absolute configurations of 20-hydroxyecdysone and cyclic-22,29-hemiacetal-22R-stigmast-7-en-29-al,2β,3β,11α,20α,22,28-hexahydroxy-6-oxo were confirmed by X-ray crystal-structure analyses of their acetyl derivatives.

中文翻译：

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来自 Rhaponticum acaule (L.) DC 地下部分的蜕皮激素

除了两种已知的蜕皮激素、20-羟基蜕皮激素和土耳其酮之外，还从 Rhaponticum acaule (L.) DC 的地下部分分离了三种以前未描述的柱头型蜕皮激素。通过色谱技术（CC、VLC、MPLC）。化合物的结构通过化学（乙酰化）和光谱方法确定，包括 UV、IR、HRMS、1D-NMR：1H-NMR、13C-NMR、DEPT-135。和 2D-​​NMR：COSY、NOESY、HSQC、HMBC。两种化合物作为异构体混合物被分离出来，它们中的每一种都被纯化并转化为相应的乙酰化衍生物。基于所有的证据，三种未描述的柱头柱头型蜕皮甾体的结构被确定为 2β,3β,11α,20β,22α,24,28-heptahydroxy-6-oxo-stigmast-7-en-25,29-lactone和环状 22,29-半缩醛 22R 和 22S stigmast-7-en-29-al,2β,3β,11α,20α,22, 28-hexahydroxy-6-oxo，以及简单的名称 acaulesterone 和 rhapocasterones A 和 B 分别被建议。20-羟基蜕皮酮和环-22,29-半缩醛-22R-stigmast-7-en-29-al,2β,3β,11α,20α,22,28-hexahydroxy-6-oxo 的结构和绝对构型由其乙酰基衍生物的 X 射线晶体结构分析。