Chemical constituents from the leaves of Magnolia denudata

20 compounds were isolated from the leaves of Magnolia denudata including 16 lignans, which belong to 6 structural types. Except for (7R, 8S, 1 'S) -Delta (8)'- 1 ', 4 ' - dihydro - 5 '- methoxy - 3, 4 methylenedioxy - 4 ' - oxo -7.O.2 ', 8.1 '- neolignan (6), magliflonenone (9),2, 5 '- diene-2 ', 8 '- epoxy - 5 '- methoxy - 8 -methyl - 4 ' oxo - 3,4-methylenedioxy - spiro (5,5) - undecane (10), veraguensin (16) and beta -sitosterol (20), the other 15 compounds were obtained from this species for the first time. The absolute configurations of 3 compounds (1, 4, 10) were determined by CID spectroscopy for the first time. The anti-inflammatory activities of compounds 1, 2 and 16 were assessed and 2 was shown to have significant inhibition effect on mice hind-paw edema induced by carrageenan.