[Two new C21 steroidal glycosides from Marsdenia tenacissima].

To study the chemical constituents of Marsdenia tenacissima (Roxb.) Wight et Arn.To separate compounds with various chromatography technology and to elucidate their structures by chemical and spectral analysis.Two compounds were isolated from Marsdenia tenacissima and their stuctures were determined as tenacissosides J (I) and tenacissosides K (II).Compounds I and II are new C21 steroidal glycosides.