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 (<i>S</i>)-7-hydroxy-3-((<i>R</i>)-1-hydroxyethyl)-5-methoxy-3,4-dimethylisobenzofuran-1­(3<i>H</i>)-one (the enantiomer of a natural stoloniferol derivative) also have been synthesized. The synthesis revised the structure of fusaraisochromanone to (<i>S</i>)-7-hydroxy-3-((<i>R</i>)-1-hydroxyethyl)-5-methoxy-3,4-dimethylisobenzofuran-1­(3<i>H</i>)-one