The reductive fragmentation of 7-hydroxy-9,10-dioxotaxoids.
The retro-aldol reductive fragmentation of different structural types of 7-hydroxy-9,10-dioxotaxoids was investigated, showing that the reaction is typical of taxanes and requires cerium(III) promotion with NaBH4 in protic medium and alkylboron (aluminium) hydrides in aprotic solvents. The resulting 7,8-seco-taxanes are key intermediates for the synthesis of a novel class of anticancer taxanes end