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)-delta8' -1', 4'- dihydro-5'-methoxy-3,4-methylenedioxy-4'-oxo-7.0.2', 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 CD 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.