Metabolic Products of Fungi. XXIII. On Ustilaginoidins. (3). The Structures of Ustilaginoidins B and C.

Abstract
The structures of ustilaginoidin B, C28H18O11, m.p. >300°, [α]25D-360°(dioxan) and ustilaginoidin C, C28H18O12, m.p. >300°, [α]25D-260°(dioxan) which were isolated as the pigments of Ustilaginoidea virens (COOKE) TAKAHASHI, were studied mostly by the NMR spectral analyses of their peracetates to conclude as being formulated as II (R=H) and III (R=H), respectively.