<jats:p><jats:bold>The Esmeraldines A and B, Green Pigments from <jats:italic>Streptomyces antibioticus</jats:italic>, Strain Tü 2706</jats:bold><jats:p>From a strain of <jats:italic>Sterptomyces antibioticus</jats:italic>, Tü 2706, two dark green substances, the esmeraldines A and B, <jats:bold>4</jats:bold> and <jats:bold>3</jats:bold>, respectively, were isolated. The structural elucidation was carried out by spectroscopic comparison with some simpler phenazines obtained from the same organism, saphenamycin (<jats:bold>1</jats:bold>) and related compounds, and by a series of chemical transformations. Esmeraldin B (<jats:bold>3</jats:bold>) is the 6‐methylsalicylic acid ester, and esmeraldin A (<jats:bold>4</jats:bold>) a mixture of higher saturated and unsaturated fatty acid esters of esmeraldic acid. The latter is a heterocyclic compound with seven rings and four N‐atoms, formally derived by condensation of two phenazine residues of the saphenic acid family. The esmeraldins are mixtures are of diastereoisomers.