RÉSUMÉ
In our search for bioactive secondary metabolites from marine Streptomycetes, three microbial benzopyrone derivatives [1-3], 7-methylcoumarin [1] and the flavonoides, Rhamnazin [2] and Cirsimaritin [3], were obtained during the working up of the ethyl acetate fraction of a marine Streptomyces fusant obtained from protoplast fusion between Streptomyces sp. Merv 1996 and Streptomyces sp. Merv 7409. The structures of the three compounds [1-3] were established by NMR, mass, UV spectra, and by comparison with literature data. Marine Streptomyces strains were identified based on their taxonomical studies, type of cell wall and G+C content as two different bioactive strains of the genus Streptomyces. We described additionally, the fermentation, isolation, as well as the biological activity. The isolates [1-3] are reported here as microbial products for the first time