A new oleanane triterpenoid saponin was isolated from the seeds of Dimocarpus longan Lour. The structure of this compound was elucidated as 3-O-β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranosyloleanolic acid 28-O-β-D-xylopyranosyl-(1→2)-β-D-glucopyranosyl ester (1), named longanoside C. The structure was determined by means of HR-ESI-MS in positive mode and extensive 1D and 2D NMR spectroscopic studies.

中文翻译：

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龙眼中新的齐墩果烷三萜皂苷

从龙眼种子中分离得到一新的齐墩果烷三萜皂苷。该化合物的结构被阐明为 3- O - β -D-吡喃木糖基-(1→3)- α -L-吡喃鼠李糖基-(1→2)- β -D-吡喃木糖基齐墩果酸 28- O - β -D-吡喃木糖基-(1→2) -β -D-吡喃葡萄糖酯( 1 )，命名为龙糖苷C。其结构通过正离子模式HR-ESI-MS和广泛的一维和二维核磁共振波谱研究确定。