Streptomyces griseoviridis

Roseophilin (273), a deeply red-colored pentacyclic compound isolated from the culture broth of Streptomyces griseoviridis, is a novel antitumor antibiotic. Compound 273 possesses a topologically unique pentacyclic skeleton, consisting of a 13-membered macrocycle incorporated in an ansa-bridged azafulvene, which in turn is linked to a conjugated heterocyclic ring system. The absolute stereochemistry of roseophilin, as depicted in Fig. 9, was unknown until the first total synthesis published by Tius and Harrington in 2001 [125]. All syn-... 

Burkhardt, K., Fiedler, H., Grabley, S., Thiericke, R, and Zeeck, A. (1996) New cineromycins and musacins obtained by a metabolite pattern analysis of Streptomyces griseoviridis (FH-S 1832) I. Taxonomy, fermentation, isolation and biological activity J Antibiot 49,432—437... 

Musacin C (54) cooccurs in Streptomyces griseoviridis with the cynero-mycins, 14-membered ring lactones of heptaketide origin. Administered... 

In 2001, Tills et al. used thiazolium chloride 620 as a carbene precursor in a diastereoselective intermolecular Stetter reaction 518) between the chiral donor 621 and aldehyde 622. The 1,4-diketone 623 thus obtained was then used successfully to access roseophilin (624) (Scheme 128) 517). The promising cytotoxicity of roseophilin (624), a macrocyclic pigment isolated from Streptomyces griseoviridis 524), has attracted considerable attention resulting in a number of partial and total syntheses of this alkaloid (525), and this example demonstrates nicely how (even achiral) organocatalysts can play an important role in obtaining a complex namral product. 

The first total synthesis of roseophilin (141), a novel antibiotic isolated from Streptomyces griseoviridis, employed the Negishi cross-... 

Practical levels of asymmetric induction can be achieved through the use of camphor. Scheme 19.32 shows the key step in the first asymmetric synthesis of roseophilin, a strep-tomyces-derived natural product. Roseophilin was isolated in 1992 by Seto and co-workers from Streptomyces griseoviridis The natural product has activity against K562 human erythroid leukemia cells with an IC50 of... 

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