Novel 4beta-amino podophyllotoxin congeners as anti tumour antibiotics a process for the preparation thereof

A process for the preparation of 4β-amino podophyllotoxin congeners of general formula A as antitumour antibiotics

• and the said process comprising the steps of:
• a) reacting podophyllotoxin of formula 1
• with sodium iodide in dry acetonitrile, under stirring, followed by adding drop wise BF3OEt2 at a temperature of 0-1° C. and continuing the stirring for a period of 0.3-0.6 hrs, at a temperature of 20-30° C., followed by evaporation in vacuo to obtain the compound of formula 2a,
• OR
• reacting podophyllotoxin of formula 1 with sodium iodide in dry dichloromethane, under stirring, followed by adding drop wise BF3OEt2 at a temperature of 0-1° C. and continuing the stirring for a period of 5-6 hrs, at a temperature of 20-30° C., followed by evaporation in vacuo to obtain the compound of formula 2b,
• c) reacting the above said compound of formula 2a or 2b with anhydrous barium carbonate and the reagent selected from the group consisting of 1-anthraceneamine, 1-fluorenylamine, 4β-(1″-pyrenylamino)-4-deoxypodophyllotoxin, 1-pyrenylamine, 6-chrycenylamine, 4-amino-4′-fluorobenzophenone and 4-amino-4′-[di(2-chloroethyl)amino]benzophenone in dry tetrahydrofuran (THF), under nitrogen and stirring for a period of 7-9 hrs, at a temperature of 20-30° C., followed by filtration, washing with water and drying by known method to obtain the desired corresponding compounds of formula 3a-f and 4a-f, respectively.