Steroidal saponins from Asparagus dumosus

A new steroidal saponin, dumoside, characterized as (20 S)-3β,16β-dihydroxy pregn-5-ene-22-carboxylic acid (22,16)-lactone-3- O-β-chacotrioside, was isolated from the whole plant of Asparagus dumosus Baker and the structure was deduced from spectral data. In addition to dumoside three more steroidal saponins characterized as 3β-dihydroxy pregn-5,16-dien-20-one 3- O-β-chacotrioside, 3β,22α,26-trihydroxyfurost-5-ene-3- O-β-chacotrioside-26- O-β- d-glucopyranoside and its corresponding 22α- O methoxy analogue were also isolated for the first time from this source. The structures have been identified with the help of FAB-MS, 1H NMR, 13C NMR and extensive 2D NMR spectroscopy, as well as comparison with reported spectroscopic data.