Roseophilin,1 a cytotoxic pigment produced by Streptomyces griseoviridis 2464-S5, has a unique structure containing two pyrrole and one furan rings as shown in Figure 1. The strain also produces a structurally related tripyrrole antibiotic, prodigiosin R1.2 Recently, we identified the rph gene cluster for prodigiosin biosynthesis in S. griseoviridis. 3 The rph cluster, however, does not contain genes characteristic of roseophilin biosynthesis, although roseophilin is considered to be biosynthesized partially with the same pathway as prodigiosin R1. We attempted to search the biosynthetic intermediates of roseophilin for further biosynthetic study. Color-guided fractionation of the culture extract resulted in the isolation of a new metabolite, dechlororoseophilin (1, Figure 1). We report herein the fermentation, isolation, structure elucidation and biological activity of 1.