Alangchnin A (1), a new isoflavonoid, together with two known compounds (2 and 3), was isolated from the roots of Alangium chinense. The structures of these compounds were established by HR-ESI-MS, and 1D and 2D NMR experiments. Due to the rotation of the flexible single bond, the absolute configuration of compound 1 was further elucidated using ECD quantum chemical calculations.

中文翻译：

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海棠根中一种新的异黄酮

Alangchnin A ( 1 )，一种新的异黄酮，连同两种已知的化合物（2和3），是从Alangium chinense的根中分离出来的。这些化合物的结构是通过 HR-ESI-MS、1D 和 2D NMR 实验确定的。由于柔性单键的旋转，使用 ECD 量子化学计算进一步阐明了化合物1的绝对构型。