New natural compounds from Rhododendron lepidotum

Phytochemical investigation of the aerial parts of Rhododendron lepidotum yielded 8-[2′,6′-dimethoxy-4′-(1″,2″,3″-trihydroxy-propyl)-phenyl]-7-hydroxy benzopyranone (1), 3-O-β-d-glycopyranosyl betulinic amide (2) and 8-hydroxy-7,7′-oxydicoumarin (4) and five known compounds. Among the known molecules, betulinic amide (3) was earlier reported as a semi-synthetic product. The structures of new molecules 1, 2 and 4 were elucidated on the basis of extensive spectroscopic investigations (1D NMR, 2D NMR and mass spectrometry).