Structural elucidation of four new furostanol saponins from Tupistra chinensis by 1D and 2D NMR spectroscopy

Four new furostanol saponins (1-4), two pairs of diastereoisomers, were isolated from methanolic extracts of Tupistra chinensis rhizomes and their structures were assigned from (1)H and (13)C NMR spectra, DEPT, and by 2D COSY, NOESY, HMQC, and HMBC experiments.