previously known germacranolide artemisiifolin were isolated. The conformations of the 10‐membered germacra‐1(10)E,4Z‐diene ring system of this compound and those of its derivatives 11,13‐dihydroartemisiifolin, isabelin and 6α‐hydroxy‐15‐oxogermacra‐1(10)E,4Z,11(13)‐trien‐12,8α‐olide were studied by NMR spectroscopic methods. Low‐energy conformations were obtained by quantum mechanical calculations. An x‐ray
从Staehelina dubia 的
丙酮提取物中分离出大量先前已知的germacranolide artemisiifolin。该化合物的 10 元germacra-1(10)E,4Z-二烯环系统的构象及其衍
生物 11,13-二氢
青蒿素、伊莎贝尔素和 6α-羟基-15-oxogermacra-1(10)E, 4Z,11(13)-trien-12,8α-olide 用核磁共振光谱方法研究。通过量子力学计算获得低能构象。
青蒿素的 X 射线衍射分析表明,在结晶状态下,它具有独特的构象,与
丙酮-d6 溶液中存在的大多数构象相对应。版权所有 © 2004 John Wiley & Sons, Ltd.