Preparation of glucosidic derivatives of steganol

Glucoside derivatives of steganol (1) analogous to the semisynthetic podophyllotoxin derivative, VP 16–213, were prepared. Glucosidation of steganol (1) with 2,3,4,6-tetra-0-benzylglucopyranose gave the a-anomer (7) of the glucoside as the major product. Subsequent removal of the benzyl groups and reaction with acetaldehyde dimethyl acetal gave the ethylidene derivative 10. The β-anomer (8) of the glucoside was similarly converted to 12. All derivatives prepared were screened for activity in the DNA breakage assay.