Total Syntheses of Stoloniferol B and Penicitol A, and Structural Revision of Fusaraisochromanone.

The first total synthesis of stoloniferol B and penicitol A has been achieved. Stoloniferol B, which is the common structure of citrinin derivatives, has been constructed by a sequential elaboration that includes a stereoselective vinylogous Mukaiyama aldol reaction, a thermal esterification with methyl acetoacetate, an intramolecular Michael reaction, and a vinylogous Dieckmann cyclization. The enantiomer of the proposed structure of fusaraisochromanone and ( S)-7-hydroxy-3-(( R)-1-hydroxyethyl)-5-methoxy-3,4-dimethylisobenzofuran-1(3 H)-one (the enantiomer of a natural stoloniferol derivative) also have been synthesized. The synthesis revised the structure of fusaraisochromanone to ( S)-7-hydroxy-3-(( R)-1-hydroxyethyl)-5-methoxy-3,4-dimethylisobenzofuran-1(3 H)-one.