Abstract: The Tuberostemoenone 1 and Tuberostemonone 2 were isolated from the roots of Stemona tuberosa Tour of the north part of China.In this paper, the 2D NMR gradient inverse techniques(GCOSY, GNOESY, GHM QC and GHMBC)were successfully applied to determine the structures of compounds 1 and 2.Tuberostemoenone 1 is a new alkaloid with novel skeletone.All of the ¹H and ¹³C NMR chemical shifts of compounds 1, 2 were assigned by 2D NMR, and their relative configurations were discussed.The structures of compounds 1, 2 were simulated by computer molecular modelling, their results were the same as 2D NMR.

Key words: Tuberostemoenone, Tuberostemono ne, 2D NMR, Gradient field