NOVEL INTERMEDIATES FOR THE PREPARATION OF CAMPTOTHECIN ANALOGUES

摘要

The present invention relates to novel intermediate compounds of formula (Ia) and its salts thereof, wherein R is an amino protecting group, R₁ is selected from the group consisting of hydrogen, an alkyl, araalkyl, hydroxymethyl, carboxymethyl, acyloxymethyl, trialkylsilyl or an N-substituted alkyl amine where nitrogen forms the linking atom. The invention also relates to the use of these novel intermediate compounds of formula (I_a) for the preparation of camptothecin analogues and its salts, more particularly the anti-cancer drug irinotecan and its pharmaceutically accepted salts.