<jats:p>Phenazine-1-carboxylic acid (<jats:italic>Ia</jats:italic>) and 6-(3-methyl-2-butenyl)phenazine-1-carboxylic acid (<jats:italic>IIa</jats:italic>) were isolated from the mycelium of the strain <jats:italic>Streptomyces cinnamonensis</jats:italic> ATCC 15 413. Identification and structure elucidation were performed by spectroscopic methods. Both compounds weakly inhibit the growth of gram-positive bacteria.