The isolation and structure identification of two new diarylheptanoids from Dioscorea spongiosa

Objective: To study the chemical constituents of Dioscorea spongiosa. Methods: The compounds wereisolated and purified by macroporous adsorption resin, silica gel column chromatography and preparative TLC chro-matography and their structures were identified on the basis of their physicochemical and spectral data. Results: Fivecompounds were obtained from the CHCl3-MeOH (V:V=10:3) fraction of 90% ethanol extract. Their structures wereelucidated as (3R, 5S, 7S)-1,7-diphenyl-3,7-epoxy-5-hydroxy-1-heptanone (Diospongin A,1), (3S, 5S, 7S) -1,7-diphenyl-3,7-epoxy-5-hydroxy-1-heptanone (Diospongin B,2), (+)-syringaresinol(3), piperitol(4), sesaminone(5).Conclusion: Compounds 1 and 2 are two new diarylheptanoids. Compounds 3, 4 and 5 were obtained from Dioscoreaas three lignans for the first time.