B. (5R,5aS,8aR,9S)-9-[(4,6-O-(R)-ethyliden-β-D-glukopyranosyl)oxy]-5-(4-hydroxy-3,5-dimetho- xyfenyl)-5,8,8a,9-tetrahydroisobenzofuro[5,6-f][1,3]benzodioxol-6(5aH)-on (pikroethylidenlignan P; cis-etoposid),