Podophyllotoxin analogues: synthesis and computer modelling investigation of structure-activity relationships

The conformations of four 2-substituted-4-deoxy-analogues of podophyllotoxin have been studied using data obtained from X-ray structure determinations and molecular modelling studies. In these, root mean square differences between these structures and those of the cytotoxic agents 6'-bromopodophyllotoxin and colchicine were determined. Attempts have been made to correlate structure with the available biological activity data.