A UNIFIED STRATEGY FOR THE TOTAL SYNTHESIS OF THE ANGUCYCLINE ANTIBIOTICS SF 2315A, URDAMYCINONE-B, AND THE SHUNT METABOLITE-104-2

Total syntheses of the angucycline antibiotics SF 2315A (2), urdamycin one B (4), and the shunt metabolite 104-2 (5) are described, as well a s an approach toward the synthesis of SF 2315B (3). All four syntheses feature a Diels-Alder cycloaddition between a bromojuglone derivative and an optically active diene (25a), the latter derived from (-)-quin ic acid. Subsequent key transformations include (i) stereocontrolled i ntroduction of ring fusion oxygen functionality featured in SF 2315A ( 2) and SF 2315 B (3), (ii) preparation of C-glycosyl juglone 53, and ( iii) NMO mediated oxidative aromatization of 60.