3. Naphthopyranquinone Antibiotics: Novel Enantioselective Syntheses of Frenolicin B and Some of Its Stereoisomers

Article abstract of DOI:10.1002/hlca.19970800104

Two new enantioselective syntheses of the naphthopyranquinone antibiotic frenolicin B (1), of its enantiomer 2, and of its diastereoisomers 3 and 4 were accomplished using two different routes from optically active β-hydroxy esters (R)- and (S)-11 and 18.