Etoposide EP Impurity B

Chemical Name: (5R,5aS,8aR,9S)-9-[[4,6-O-[(1R)-ethane-1,1-diyl]-b-D-glucopyranosyl]oxy]-5-(4-hydroxy-3,5-dimethoxyphenyl)-5,8,8a,9-tetrahydro[2]benzofuro[5,6-f][1,3]benzodioxol-6(5aH)-one (picroethylidene-lignan P; cis-etoposide)