A novel coumarin (1, mucodianin A), three new 2-arylbenzofurans (2-4, mucodianins B-D) along with four known ones were isolated from the vine stems of Mucuna birdwoodiana. Their structures were elucidated on basis of spectral analysis. This is the first report of 7-quinonylcoumarin (1) as stable form in natural products.