A new stereocontrolled entry into the anthracyclinone families. Part 1. Synthesis of bicyclic precursors of 4-demethoxy-7-deoxy-derivatives

A new and versatile strategy to obtain enantiomerically pure bicyclic precu rsors of compounds belonging to different anthracyclinone families is repor ted. Completely stereoselective hydrocyanation of (R)-4-(2,5-dimethoxypheny l)-1-p-tolysulfinyl-2-butanone and further intramolecular capture of the Pu mmerer intermediate generated from the resulting sulfinylcyanohydrin are th e key steps to obtain the bicyclic nitrile 2 with the proper configuration and functionality at C-9. (C) 1999 Elsevier Science Ltd. All rights reserve d.