<jats:title>Abstract</jats:title> <jats:p>Chemical investigation of terrestrial and marine streptomycete isolates led to the identification of two new natural pigments, namely, 6-hydroxyisatin (<jats:bold>3</jats:bold>) and 6-hydroxy-5-methoxyisatin (<jats:bold>4</jats:bold>). Additionally, the strains delivered numerous known compounds, among them <jats:italic>N</jats:italic> <jats:sup> <jats:italic>β</jats:italic> </jats:sup>-acetyltryptamine, <jats:italic>N</jats:italic>-acetyltyramine, phenylacetamide, <jats:italic>N</jats:italic>-(2-phenethyl)acetamide, 1-acetyl-<jats:italic>β</jats:italic>-carboline, tyrosol, 2′-deoxyadenosine, 2′-deoxythymidine, anthranilic acid, 2′-deoxyuridine, indolyl-3-acetic acid, indolyl-3-carboxylic acid, and <jats:italic>p</jats:italic>-hydroxybenzoic acid. The isatin structures were deduced by NMR and mass studies and further confirmed by synthesis and by X-ray diffraction of the isomeric 5-hydroxy-6-methoxyisatin (<jats:bold>5</jats:bold>).