Intermediates for the production of picropodophyllin and related compounds and processes for the preparation and use thereof

摘要

The present invention provides compounds having the structure: <IMAGE> VI wherein R1 represents alkoxy or aralkoxy, R2 represents hydrogen, alkoxy, aralkoxy, alkyl, aralkyl, or R1 and R2 taken together represent the group -O-CH2-O-, R3 represents hydrogen, alkyl, aralkyl, acyl or a protecting group, Y represents Cl, Br, I or a leaving group, and X represents Cl, Br or I.