Three New Steroidal Glycosides from the Roots of Cynanchum auriculatum

Abstract: Three new steroidal glycosides, cyanoauriculosides F, G and H ( 1 - 3 ), were isolated from the roots of Cynanchum auriculatum (Asclepiadaceae) along with two known steroidal derivatives. On the basis of spectroscopic analysis and chemical methods, their structures were identified as 20- O -acetyl-8,14-seco-penupogenin-8-one 3- O -α- L -cymaropyranosyl-(1→4)-β- D -cymaropyranosyl-(1→4)-α- L -diginopyranosyl-(1→4)-β- D -cymaropyranoside ( 1 ), 2′,3′ - Z -gagaminine 3- O -α- L -cymaropyranosyl-(1→4)-β- D -cymaro-pyranosyl-(1→4)-α- L -diginopyranosyl-(1→4)-β- D -cymaropyranoside ( 2 ), 17- O -acetyl-kidjoranin 3- O -α- L -cymaropyranosyl-(1→4)-β- D -cymaropyranosyl-(1→4)-α- L -cymaro-pyranosyl-(1→4)-β- D -digitoxopyranosyl-(1→4)-β- D -digitoxopyranoside ( 3 ), gagaminine 3- O -α- L -cymaropyranosyl-(1→4)-β- D -cymaropyranosyl-(1→4)-α- L -digino-pyranosyl-(1→4)-β- D -cymaropyranoside ( 4 ) and wilfoside D1N ( 5 ). Keywords: Cynanchum auriculatum ; steroidal glycosides; cyanoauriculosides